Volume 26 (2022): Issue 1 (January 2022)

Wind energy is one of the most important ways to implement green energy in Lithuania. The development of wind energy infrastructure by state funding is directly related to wind energy resources. Changes in wind energy resources induced by ongoing climate change have not been well analyzed either in Lithuania or in Europe or worldwide. This article analyses data taken from long-term wind observations and IPCC projections. It was found that during the last decades (1980–2019), the wind speed in Lithuania decreased up to 0.69 m/s in the coastal region and up to 0.24 m/s in the central part of Lithuania. The decrease in wind speed caused a decrease in generated energy by 15.6 % and 17.8 % in the coastal and the central parts of Lithuania. Analysis of wind speed projections for the period 2010–2100, according to the RCP4.5 scenario, has shown that the average annual wind speed would decrease by 7.3 % in Lithuanian’s coastal region and 8.8 % the central region by the end of the century. The change in wind speed will cause up to a 25 % reduction in wind potential. As the average lifetime of wind turbines is about 25 years, the amount of electricity generated during this period will be up to 20 % lower than planned at the design stage.

All European Union (EU) member states till 2020 had an obligatory target for energy efficiency. One of instruments for countries to achieve national energy efficiency goals is obligation for large companies (LC) and large electricity consumers (LEC) to implement certified energy management system or perform energy audit. In this study the Latvian case study of obligation for LC and LEC where examined. The analysis was carried out using a theory-based policy analysis method combined with evaluation criteria from the EU legislative assessment guidelines The Better Regulation Agenda – efficiency, effectiveness, relevance, coherence, added value, validity, complementarity, coordination, equality, sustainability and acceptability. To evaluate energy efficiency policy measures, it is also important to understand energy efficiency measures that will realistically meet the set company and national targets. AHP and TOPSIS analyzes were performed to evaluate these measures not only from energy efficiency but also from environmental, climate, engineering-technical, economic, and social aspects. The results allow us to assess the fate of existing policies and to draw conclusions on the improvements needed to meet energy efficiency and climate goals in the future.

This work evaluates the impact of cultivating Safflower (Carthamus tinctorius L.) in marginal lands of the Umbrian territory (Italy) to produce oil. The analysis considers the entire production process, aiming to understand which are the most impacting factors. In particular, the work assesses the environmental savings deriving from the reuse of the main by-product of the oil extraction process, i.e. the cake, for animal feed purposes. The evaluation was carried out by means of a cradle-to-gate LCA. The results show that the greatest impacts are due to the crop fertilization. However, such an impact is almost completely compensated by the use of the cake in feed production.

The results of a first campaign of sampling and analyses of emerging micropollutants in the influent (municipal centrate) and effluent of a pilot MBP raceway are reported. The algal population was chiefly made of Chlorella spp. and the pilot worked satisfactorily for the removal of nitrogen. 14 emerging micropollutants were analysed. Average removal efficiencies exceeding 80 % were observed for diclofenac, lamotrigine, ketoprofene, clarithromycin. For such compounds the variability of removal efficiency was also reduced, with respect to the other tested molecules, and was particularly low for diclofenac and lamotrigine. Removal efficiencies over 50 % were measured for azithromycin, metoprolol and irbesartan but with strong variability. Lower removal efficiencies were observed for amisulpride and 5-methylbenzotriazole, while for the remaining compounds the concentrations in the effluent were higher than in the influent.

Environmental Management Systems (EMS) represent a solid opportunity for companies that voluntarily undertake a path towards the adoption of environmental protection policies. Many studies investigated the link between EMS and improvement of environmental performance, demonstrating how the adoption of an international standard as ISO 14000 or EMAS guarantees the company an improvement in its performance and an increase in transparency towards stakeholders. However, scientific research in this field reflects the strong variability due to the breadth and diversity of sectors in which the two international standards can be adopted. The aim of this work is to analyse, through textual statistics and text mining methods, the trends that characterize scientific production, highlighting most debated topics useful for developing new research perspectives in this research field.

Among other sectors prioritized in delivering the circular economy targets, such a major sector as health care should also be highlighted. According to World Bank data, current health expenditure is still rising, reaching globally 10.02 % in 2016 compared to 8.56 % in 2000. To ensure protection of public health, the management of health care waste should be based on the waste management hierarchy. Besides the preventive measures (waste minimization, green procurement, sustainable planning, environmental management systems), treatment methods should also be viewed in the context of the waste management hierarchy. To analyse the possibility to apply circular economy principles into health care waste management, evaluation of resource recovery alternatives as well as its multi-dimensional assessment was done. In the article quantitative and qualitative assessment was conducted through multicriteria decision analysis with a goal to do a quantitative and qualitative assessment of healthcare waste and resource potential assessment.

Evolving complex concepts, such as bioeconomy, in the most effective way, can be applied through the education of students and professionals. In recent years changes in the education system can be observed with the development of knowledge-based learning. Competence-based learning will also be used more and more in higher education. Higher education plays a crucial role in achieving the goals of the Green Deal and the bioeconomy. The main emphasis is on creating new and innovative technologies and methods to achieve these goals. A new master’s study program, ‘Environmental Engineering’, has been established at the Institute of Energy Systems and Environment of Riga Technical University. One of the study directions is ‘Bioeconomy’. Considering the developed direction ‘Bioeconomy’, the importance of this sector is visible. Attention should also be paid to the goals of the Green Deal. This study summarised research on education, bioeconomy and Green Deal topics and analysed the interrelationships between these studies using the VOSviewer tool. During the analysis, it is possible to conclude the main keywords that characterise these studies. The obtained keywords should indicate the development trends of future research, which is in line with education, the ‘Green Deal’, and bioeconomy.

The extraction of Biodiesel from vegetable oil is time-consuming and requires human involvement to perform and keep track of chemical titration, stirring, and washing the product for each batch of production. A well-designed system can significantly eliminate human interaction and expedite the whole process. The construction of an inexpensive automated biodiesel plant can help produce Biodiesel on a large scale and make a breakthrough in Bangladesh’s economy as no such effort has been undertaken so far. To achieve the desired aim, this paper focuses on implementing the construction of a cheap, compact, and automatic system that will exhaustively reduce human interactions and the processing time and increase biodiesel yield. For this purpose, an automated biodiesel processor was designed and constructed in conjunction with pumps, solenoid valves, level sensors, temperature sensors, etc., using a programmable logic controller (PLC). Upon completing a full cycle, the plant delivers certified Biodiesel and the leftover by-products are collected for further recycling. Different batches of Biodiesel were produced. A comparative study of the physical properties of the fuel and the diesel engine’s performance characteristics by these fuel samples was analysed and showed satisfactory results.

Nowadays national and international directives have focused on improving energy efficiency in the building sector. According to them, energy consumption and emissions of buildings must be reduced. This can be achieved by balancing energy demand in buildings. In this context, this paper proposes a buildings’ energy demand balancing method using the building energy consumption simulation program IDA ICE and real measurements. A 3D model of the building was developed, energy consumption and indoor climate of the building was monitored throughout the year, the behaviour of the occupants (a survey was conducted) was analysed, dynamic change of the weather was studied and all data were integrated into IDA ICE simulation. In order to increase the energy efficiency of buildings, the possibilities of optimization of heat production equipment and heating devices, as well as inspecting and optimization of ventilation and cooling equipment were considered. By adjusting the parameters of the heating system of the researched object, the energy consumption of the auto centre decreased to 39.3 kWh/m² per year. One of the most popular methods of balancing energy demand in recent years – the creation of smart grids – is also considered.

The dynamics of global energy and climate agenda progresses rapidly. The European Union has frequently taken an active role in international climate policy by developing relevant strategies in as early as the nineties the last century, and today promoting an ambitious EU Green Deal to become climate neutral by 2050. However, despite its ambition and recent success in meeting most 2020 goals, the EU does not have an easy schedule to progress on its climate and energy targets for 2030. Recognizing the transition, one of the scientific excellences European Organisation for Nuclear Research (CERN) published the first environmental report in the beginning of 2020. Through a wide range of environmental activities and clearly disseminated targets, this organisation actually brought to the table a discourse on how scientific organisation can be part of EU Green Deal actions and how to perform research within the scope of the environmental context. This article focuses on two concepts to contribute to larger discussions in both the research and governance communities, how researchers should conduct their science, and what respective responsibilities of researchers, their institutes, have in terms of European environmental policy. Literature was reviewed to find a theoretical approach to the environment, responsible innovation and science diplomacy. The research was developed through literature study to identify and describe the respective indicators as well as through an analysis of secondary sources whereby a previous attempt to collect and analyse other sources had been conducted by scholars in respect to the relationship between innovation and the environment.

The number of vehicles in Bandung City continues to increase every year in line with the growth of motorized vehicle repair shops, thereby increasing the generation of hazardous waste from automotive shop activities. Based on Indonesia’s Governmental Decree 101 of 2014, vehicle maintenance and repair activities are one of the businesses that produce hazardous waste. This study focused on licensed and unlicensed automotive shops in Bandung City using stratified sampling methods by determining waste generation and composition, evaluating existing management systems, followed by developing management system alternatives. In determining the generation and composition of hazardous waste from automotive shop activities, a sampling of 42 unlicensed automotive shops and 11 unlicensed automotive shops in 3 areas of Bandung City was conducted. Sampling results of hazardous waste generation are 1.83 kg/vehicle/day for motorcycle automotive shops and 6.90 kg/vehicle/day for car automotive shops. The largest composition of hazardous waste produced in licensed shops is used oil with a proportion of 29.60 % and metal scrap component with a proportion of 35.83 % for unlicensed automotive shops. The projection results of hazardous waste generation in 2021 are around 774.26 tonnes/day. If the hazardous waste generated is not properly managed it can pose a risk to human health and the environment. An integrated management system for hazardous waste consists of packaging activity, storage activity, collection, transportation, and recycling activity.

The article presents the types and classification of waste from the phosphorus industry of the Zhambyl region of the Republic of Kazakhstan. Waste is classified by its use as recyclable materials for construction materials. The results of a comparative assessment of the physical, chemical and structural properties of the phosphorus industry waste are presented. The article shows that all studied types of waste have astringent properties and can be used as building materials. In this work, a study of the properties of large-tonnage wastes of the phosphorus industry was carried out: 1) electrothermophosphoric granular slag (granulated slag); 2) phosphogypsum; 3) overburden. A technology has been developed for producing non-fired binders from waste of the phosphorus industry and a methodology for designing the composition of raw mixtures of multicomponent building composites has been proposed.

Pilot tests and calculation of technical and economic indicators have been carried out, which have shown the economic feasibility of producing a non-firing binder for the construction industry from phosphorus production waste.

Regarding climatic diversity in Iran and the dependence of many outdoor activities (occupational, recreational, tourism attraction, etc.) on climatic conditions, this study conducted aiming to evaluate thermal comfort fluctuations in Iran. Thermal comfort fluctuations in different climates of Iran were investigated between 1985 and 2014 using recorded meteorological data in 40 synoptic stations. The Mann-Kendall test and Sen’s Slope were used to analyse the changing trends of the Humidex and to determine the actual slope of a trend over time, respectively. In overall, the southern areas of Iran have the longest period with unfavourable and extremely unfavourable climatic conditions in this study. Conversely, in the northern half of Iran, especially in North West areas, the appropriate summer season provides the best climatic conditions for outdoor activities.

The United Nations announced its 2030 Agenda for Sustainable Development worldwide in 2015. Comprehensive assessments of member states’ performance towards achieving the related UN Sustainable Development Goals (SDGs) have since become a major challenge for national and subnational governments. This article presents a bibliometric analysis on the assessment of SDGs, at both the general and specific levels, based on 418 publications obtained from Scopus. The general level of analysis includes the number, types, and subject areas of documents published each year, as well as considerations such as the most-cited publications and the leading authors, journals, countries, institutional affiliations, and funders. The specific level of analysis includes a study of the relevant concepts in the publications and their relationships, allowing for the identification of predominant assessments under the 2030 Agenda, and of the most-often evaluated SDGs. Results indicated a focus on measuring impacts and risks, with SDGs 3, 6, 13, 7, 8, and 4 having been assessed the most often among the 17 SDGs, which is consistent with findings in prevalent subject areas such as environmental sciences, social sciences, medicine, and energy. Future works should address assessments under the 2030 Agenda more comprehensively, including analyses on trade-offs among the SDGs and on the transversal nature of some of these goals.

The monitoring of tourist traffic helps to manage tourism in national parks. Today park managers and researchers use many different devices and technologies that facilitate data collection. Among these often used devices is the pyroelectric sensor. Despite its high degree of usefulness, this type of sensor can miscalculate. Therefore, there is a need to assess the magnitude of errors and the circumstances in which they occur. The purpose of the study was to evaluate pyroelectric sensor counting errors in relation to different visitor flow levels and time intervals between visitors. The study was based on a field experiment and on-site observations using pyroelectric sensors, part of the Monitoring System of tourist traffic (MSTT) in Stołowe Mountains National Park in Poland. The outcome of the assessment was the errors sizes and types and calibration formula. Pyroelectric sensors more often overcount than undercount. Errors occur in larger than 6-visitor groups and time intervals between visitors shorter than 3 seconds. Finally, the analysis of the causes of errors gave the ground to generate the typology of error circumstances. The calibration formula was generated based on a field experiment and on-site observation. The average error size was reduced from ±13 % to ±6 %. The calibration formula provided in the study is simple and universal and can be applied to other data.

This presents the analysis of the main reasons for a significant decrease in the intensity of diffusion processes during formation of gas hydrates; solutions to this problem are proposed in a new process flow diagram for the continuous synthesis of gas hydrates. The physical processes, occurring at corresponding stages of the process flow are described in detail. In the proposed device, gas hydrate is formed at the boundary of gas bubbles immersed in cooled water. The dynamic effects arising at the bubble boundary contribute to destruction of a forming gas hydrate structure, making it possible to renew the contact surface and ensure efficient heat removal from the reaction zone. The article proposes an assessment technique for the main process parameters of the synthesis of gas hydrates based on the criterion of thermodynamic parameters optimization.

The paper describes the problem of using the vehicle’s suspension as a source of an alternative energy. One of the best ways to improve the vehicle efficiency and its smooth ride is to make some rational changes in the vehicle design, one of which is to convert the mechanical energy accumulated in the vehicle’s suspension into electricity. The shock absorber in the suspension has been replaced with two different-type new recuperative devices, which replace the shock absorber and convert into electricity the loads coming from the road irregularities to pavement.

The energy management in energy systems is the main solution for energy companies in order to provide minimization of the energy generation costs and emission polluting. In this work, a multi-criteria optimization model is implemented for minimizing the generation cost and emission in a smart micro grid (SMG) at day-ahead planning. In this modelling, the demand side participates in optimal energy management through two strategies such as demand shifting and onsite generation by the energy storage system (ESS). The optimal participation of demand side is modelled based on energy price in energy market. Implementation of the proposed approach in GAMS software is done, and weight sum method (WSM) is employed for solving multi-criteria optimization. The desired optimal solution of multi-criteria objectives is found via the max-min fuzzy procedure. Finally, confirmation of the proposed approach is analysed by numerical simulation in two case studies.

Food wastage is a complex global issue. Its solution requires a multi-pronged effort and the use of diversified strategies. Since the impacts are on an environmental, social and economic level, solutions can take shape in one of these areas, knowing that there are often trade-offs between one and the other. This paper aims to evaluate the net environmental effects in terms of Carbon footprint of the activities of the Lithuanian Food Bank (Maisto Bankas). Food banks are charities that work to reduce the negative social effects associated with food waste and food insecurity. They work on the food recovery, avoiding the transformation of food surplus in food waste. The present paper assessed the positive impact generated by the Lithuanian Food Bank thanks to its activities as the non-impact of recovered food and the non-disposal of food in landfills. At the same time, also the negative impact in term of emission due to the management of all its activities has been estimated. The net impact has been derived by the comparison of the two flows. The results of the study proved that, behind the social benefit, the Food Banks, as Maisto Bankas, produce also a net positive environmental impact.

Energy viability and waste disposal have been the two significant global complication. The consumption of paper and, subsequently, recycling are increasingly growing, contributing to vast quantities of paper sludge. Therefore, in waste disposal and environmental remediation, coping with massive volumes of paper sludge has received tremendous attention worldwide. Our purpose was to assess leading study advancements globally of paper sludge based on articles published, authors intra/inter-collaborations and accumulations of keywords. Throughout entire 1967–2019 duration, 2096 publications in paper sludge topic were mined using Scopus database. The findings revealed that the number of publications was less than 30 between 1967 and 1995, less than 60 between 1996 and 2005, less than 90 between 2006 and 2010 and more than 90 between 2011 and the recent year. Consequently, the yearly publishing is forecast to keep to expand. In a total of 125 journals, a total of 217 Canadian scholars from 155 universities lead to 263 papers, comprising 10.8 % total publications, where 261 (99.2 %) of 263 total English-language publications dominate the other countries/territories, while 0.8 % in French language. Also, from each of the 15 top countries, among the most productive universities, Université Laval was ranked 251^st in World University Rankings 2021. In review, the following present developments in paper sludge comprise of: (i) cement, cellulose, bioethanol/biogas and concrete; (ii) phytoremediation and vermicompost and (iii) modelling (e.g., response surface methodology).

This research examines the factors that affect Photo Voltaic (PV) solar technology’s usage intention in rural households in Bangladesh. The conceptual model for this research was developed according to past studies. There were five hypotheses developed and verified in this study. Cross sectional quantitative method was used in this research. The model was tested using empirical data collected from 209 households. This research mentions that PV solar technology usage intention was predicted by environmental concern, environmental knowledge, adoption cost, awareness, and government initiatives. The model shows a larger proposition (95 %) in the variance of PV solar technology usage in rural households in Bangladesh. According to the results of this study, we have accepted all hypotheses (H1–H5). From a practical perspective, this study’s results provide a guideline for investment decisions for the usage of PV solar technology in Bangladesh.

In this paper, a newly developed dynamic simulation model for transport user behaviour analysis is presented. The study aims to evaluate the impact of various factors on human behavioural intentions, identify the inconvenience costs of public transport, and identify the necessary improvements to shift the demand for population mobility from private cars to public transport. The assessment of such aspects as travel time and travel cost is presented. Modelling assumptions are based on a specially designed public survey allowing to improve the reliability of the developed system dynamics model. Modelling results highlight the multiplicative effect of factors influencing mode shift.

The COVID-19 pandemic has had a great impact on energy consumption in the world and many researchers have found very different energy consumption patterns. The goal of this study was to analyse the patterns of energy consumption in municipal buildings. Altogether data from 262 buildings from 4 municipalities were used and analysed. Results show very different energy consumption patterns for different types of buildings. In schools and education facilities the link between Covid-19 restrictions and energy consumption deviations are visible, but in administration and office buildings it is not the case. This leads to a conclusion that energy consumption in the buildings is not always linked to the level of occupancy of the building, meaning that there is room for improvements on energy management practices and procedures in the municipalities.

The paper studies the current state of the art in the use of acoustic effects in the prevention and elimination of fires. For this purpose, the literature review method was applied. The well-known approaches to fire extinguishing and their impact on the environment are considered. Multifaceted studies by a wide range of scientists on the possibilities of the acoustic effect in fire extinguishing are noted. The analysis of literary sources showed the negative impact of both the fires themselves and the majority of fire extinguishing agents on the environment. Variants of the use of the acoustic effect for the prevention and elimination of fires of various combustible substances are considered. The influence of the frequency of acoustic waves, scanning speed, power, and other acoustic parameters on flame extinguishing is noted. The possibilities of using a deep neural network for flame detection have been studied. The limitations and advantages of acoustic technology and further prospects for its development as an element of environmental technologies are shown.

In recent years, the recycling of waste materials has become significant due to the movement of the European Union toward the Green Deal and the low impact on the environment. The paper studies the possibility of Waste Tyre Textile Fibre (WTTF) for sound absorption applications. WTTF is the material generated during the end-of-life tyre recycling process, which is separated from rubber and metal parts. In this study, three different types of WTTF samples were tested in which they consist of different levels of rubber impurities. In the first case, rubber particles make up to 10 % of total mass of WTTF (WTTF10), second – 54 % (WTTF54), and third – 70 % (WTTF70). The sound absorption tests were performed using the impedance tube using a two microphone technique, under the ISO 10534-2 standard. The results showed that increasing the level of rubber particles reduces the sound absorption performance of the WTTF. It was noticed that sound absorption of the sample WTTF10 reached 0.67 at low frequencies (500 Hz), while WTTF54 reached 0.31 and WTTF70 reached 0.21. It was concluded that WTTF10 samples had on average a 61 % higher sound absorption capacity compared to the other samples. The aim of the study was to determine the rubber particles impurities in WTTF dependence on sound absorption ability of the material.

The transport sector accounts for about one-third of the final energy consumption in Latvia, most of which are fossil fuels in road transport. Fossil fuel consumption increases emissions and demands an immediate change in mobility habits to achieve climate neutrality by 2050. This paper focuses on the in-depth analyses of passenger transport by modelling the potential use of cleaner energy sources and the possible decrease of consumption through the modal shift. As travel modes differ for each distance, the study is done for three distances – short, medium and long. Three scenarios have been analysed – BASE scenario including existing measures and taxation policy, NECP scenario including measures defined in the National Energy and Climate Plan until 2030 and GHG TARGET scenario aiming to achieve climate neutrality by 2050. The proposed modelling approach allows for the development and evaluation of the effectiveness of existing and planned measures in greening mobility. Results proved the need for immediate action and a change in the mobility habits of the population to achieve climate neutrality by 2050.

This article focuses on decreasing the energy taken from the electrical grid by air to water heat pumps in buildings that use renewable energy. Conventionally the majority of the produced renewable energy is not used directly to operate the heat pump. An energy management concept was developed, with a main new parameter – RCOP that enables to create an optimal working schedule that considers the renewable energy availability and heat pump coefficient of performance in relation to the weather. The concept was proven with computer models that use weather forecasts, renewable energy production, and heat demand. The achieved yearly savings in grid-electricity used by the heat pump were 14.3 %. The fluctuations in the grid load were decreased which as well were quantified by a lower standard deviation of the demand. In months with the best renewable energy availability, the grid electricity savings can reach up to 70 %.

Under free market conditions, there should be a correlation between price and demand. In the electricity market, it is not possible to shift all consumption to hours that are more favourable. Therefore, free market rules do not fully apply to the electricity exchange market. Household consumers have a better ability to shift their energy consumption. At the same time, a large number of household consumers have fixed-price contracts and are therefore not affected by the sharp price changes, so it can be said that they do not actively participate in the stock market. They do not need to shift their electricity consumption. High-consumption industrial companies have very low possibilities at all to react to the stock market changes. The aim of this study is to find out how much electricity consumption has been able to shift in a situation where electricity prices in Estonian were extremely high and volatile. Electricity prices are usually lower at night-time, so it can be assumed that consumption will be shifted to night-time if possible. Examining the change in the distribution of night- and daytime electrical consumption over the years, it is possible to analyse the effect of energy prices on consumer behaviour during periods of high volatility.

With the increase in renewable energy implementation all over the globe, the need for storage technologies is also raising, in order to match the renewables intermittent production with the demand and create a more resilient energy infrastructure. Due to its importance, in this study, a thermo -chemical heat storage system is investigated. A mathematical model of an open sorption system with a fixed zeolite 13XBF (binder-free) bed is validated using a setup assembled in the laboratory. The equipment used to perform the experiments the mathematical model, and the results obtained will be here presented. A comparison between experiments and simulation was performed and the results are satisfactory.

This research comprised an evaluation study for a charging station based on waste vegetable oil or biodiesel fuel. The biodiesel was produced from waste vegetable oil (WVO) and will be used (or the WVO) to charge electric cars for restaurant’s customers in their car park. The main concept behind the charging station is to be part of a restaurant that serves its customers and then uses its WVO or biodiesel to fuel a diesel engine that generates electricity to charge their electric vehicles (EV). The economic and environmental impacts of the direct use of WVO-EV charging station are promising because the costs associated with purchasing WVO are lower than those of purchasing crude oil or gas. There are several options and scenarios when selecting the perfect sized generator; using charging up to a maximum rated power of 6.6 kW is more feasible despite its higher initial cost as the simple payback period will be less than 3 years and the internal rate of return of the project is 44 %. The total saving at the end of the project for a generator with maximum rated power of 10 kW (option B) is $ 58 000. Conversely, for a generator with maximum rated power of 6.6 kW (option A) the project will cover its initial cost in around 4 years and the internal rate of return is 26 %. The total saving at the end of the project is $ 52 000. Furthermore, lower amount of greenhouse gases is produced from the burning of WVO directly. The final results showed that WVO is more feasible as it is available for free and could be burnt directly in the diesel engine. In economic terms, the project is feasible for both WVO and biodiesel as it has a high net present value and short payback period. A WVO-EV charging station can also improve the national economy by preparing it for the electric car era and, if applied to a large number of restaurants, will save a significant amount of electricity and reduce the expected strain on the electricity grid caused by the increasing number of electric cars.

The purpose of the study was to evaluate the possibility of removing heavy metal cations from single-metal spiked soil samples, which were pretreated with nanoscale zero-valent iron (nZVI) particles. Sandy soil was artificially contaminated with copper (Cu), cadmium (Cd), nickel (Ni), and lead (Pb). Contaminated soil samples were amended with different doses of nZVI (0.35, 0.70 and 1.05 %). A sequential extraction method was used to determine the fractionation of heavy metal cations in the control and nZVI amended soil samples. A solution of 0.1 M acetic acid (pH 3.0) was used to investigate the removal of heavy metals from control and nZVI-amended soil samples. The results showed that nZVI reduced the amount of metals in the exchangeable form and increased the proportion of these metals associated with amorphous iron (Fe) oxides. The results also showed that the removal efficiencies of heavy metals increased with increasing nZVI dose, that is, from 46.9 %, 5.77 %, 33.5 %, and 2.70 % to 55.9 %, 12.3 %, 46.2 %, and 3.79 % for Cd, Cu, Ni, and Pb, respectively. The study indicated that the application of nZVI in soil could be beneficial for subsequent removal of heavy metals from soil using 0.1 M acetic acid solution.

Replacing fossil resources with bioresources is one of the promising directions for more environmentally friendly energy production, but the production and processing of biomass generates a large amount of waste with limited use and recycling possibilities. In this respect Hydrothermal Carbonisation (HTC) offers a sustainable and cost-effective solution for disposal and creation of new products from biomass through resource recovery and through climate-neutral process. In this study the impact of biomass type and HTC conditions on the yield and properties of artificial humic substances and hydrochar to achieve carbon capture aim has investigated. A major impact on the yield of HTC products do have the duration and temperature of the treatment, as well as catalyst used (pH of the reaction) and changing the carbonisation conditions it is possible to design the desirable composition of obtained products. During HTC process significant changes of the biomass composition happens resulting in the removal of most labile components. Although the carbon dioxide sorption capacity of hydrochar is relatively low, after activation efficient sorbent (activated carbon) can be obtained, prospective for carbon capture aims.

Cold supply chains of food and beverage sectors represent one of the main drivers of the EU total final energy consumption. Within this context, food quality losses, changes in temperature regimes, energy use, environmental burdens, and the economic viability of energy efficiency measures are essential aspects to consider for improving cold supply chains’ overall sustainability. This paper presents a dedicated toolbox, developed within the Horizon 2020 project ICCEE, for supporting decision-making and actors to assess energy efficiency path within a specific type of food cold-supply (i.e., meat, fish, milk and cheese products, fruits, and vegetables). More in specific the toolbox offers support for decision-makers to understand and minimize the specific energy consumption, to decrease the overall environmental impact even including non-energy benefit evaluation many times underestimated. The six separated tools merged within a unique toolbox consider different methodological approaches such as: assessment of the whole energy requirements in stock and flows considering the storage impact, the logistics and quality losses over time, implementation of Life Cycle Assessment and Life Cycle costs within the environmental and financial assessment of energy efficiency measures, based on a benchmarking approach. Finally, a specific approach implementing Multi Criteria Analysis was developed on selected key performance indicators such as specific and cumulated energy consumptions, quality losses and environmental burdens (i.e., global warming potential and water scarcity). The latest version of the ICCEE toolbox is available as free downloadable package on the ICCEE website.

The renewable energy is expanding in the sub-systems of distribution electrical grids, due to having low energy costs and high reliability. In this study, off-grid design of the hybrid energy system based-renewable resources is proposed for a house in Hamadan city in Iran. The resources are designed based on economic and climate data such as battery, solar cells, wind turbines, and electrolyser/fuel cell. The design of mentioned resources is done with attention to twofold optimization modelling including operation cost (OC) and net present cost (NPC). The modelling of resources is implemented in HOMER software based on optimal sizing and installation costs. In the numerical simulation, the three optimal designs are presented to meet electrical demand with minimum costs and high reliability.

The Colombian energy matrix faces significant changes toward meeting its energy needs while fulfilling its pledges in the Intended National Determined Contributions linked to the Paris Agreement. The country has developed a plan for energy transition with a 2050 horizon, a strategy reflected and supported by new legislative packages. Within its design, biomass and biomass waste play a vital role in bioenergy production; however, the benefits of deploying new bioenergy production facilities have not been fully accounted for, including only an economic and climate change perspective. In this work, a Life Cycle Sustainability Assessment of a potential bioenergy plant for industrial symbiosis with the largest landfill in the country is undertaken, avoiding environmental burden shifting between environmental damage categories and exposing the social potential of such projects. The results show how these types of projects are economically feasible and have the potential to boost the sustainable development of local communities, which under the Colombian context, have been structurally relegated from conventional economic growth for decades.

The rise of photovoltaic (PV) penetration is contributing to the increasing incidence of overvoltage detection in the electrical grid during times of high-power generation. Overvoltage can cause disturbances or (partial) failures in the electrical supply network, since the components used are designed for a certain voltage band. One option to counteract too high voltage levels and thus ensure power quality, grid stability and resilience is the absorption of active power by means of a battery energy storage system (BESS). In this paper, we first built a suitable simulation setup for a typical European network section, including a large-scale PV system connected to the 10 kV level and a BESS model. A suitable charging and discharging algorithm for the BESS with the aim to realize peak shaving for the grid voltage was developed and implemented. Simulations, performed in MATLAB/Simulink^®, show the dependence of the battery capacity and power on the grid-serving effect of BESS. By determining appropriate values for these two factors a significant reduction of the voltage level could be achieved.

The problem of Climate Change and the related issues of greenhouse emissions, and energy consumption are among the most debated topics nowadays at international level. It is essential to find viable solutions also in the agri-food sector, moving towards production processes that were more sustainable, energy saver, and possibly follow a circular economy approach. The Circular Economy is not fully a brand-new concept, as it is based on a combination of fundamental and founding concepts such as Industrial Ecology, Regenerative Design, Natural Capitalism, Cradle to Cradle approach and Blue Economy. However, the novelty is in the attention that this concept is gaining among business practitioners, consultancy firms, governments, NGOs and associations, and academics. The aim of this study is to perform a Life Cycle Assessment related to one of the main products of a company of the agri-food sector in central Italy. The product analysed was fresh sausage and the functional unit considered was 100 kg of fresh sausage. The analysis was performed in order to identify the environmental impacts caused by the different transformation processes along the product life cycle, to highlight the critical phases and to plan improvements in terms of efficiency of the production process, with consequent improvement of the environmental performance. Particular attention was paid to the transport and to the energy consumption phases.

Due to the rising demand for food and feed, agricultural waste increases, while plastic pollution increases due to hostile human activities. The sustainable way to utilize agricultural waste and promote the bioeconomy concept is to produce an alternative product of plastic, i.e., ‘bioplastic’. This paper used different keywords to perform the bibliometric analysis of the scientific publication related to bioplastic, agricultural waste, and sustainability. Remarkably, results show the increasing research interest in bioplastic with the key developing trends in sustainable bioplastic production, agriculture waste management, biopolymer, and biological processes. The identified developing trends can be used for further research to create a sustainable agricultural sector and produce higher added-value products. Moreover, this study discovered that the agro-biopolymer area needs more focus on sustainable development considering the economic, social, and environmental dimensions.

Water quality in any stream is affected by complex interactions between natural and anthropogenic factors in a given catchment area. Agriculture has been identified as a major contributor of nitrogen and phosphorus inputs to surface waters in the Baltic Sea region. Although decisions regarding agricultural management practices, e.g. crop rotation, tillage, fertilization, have a direct impact on likelihood and magnitude of nitrogen and phosphorus losses from agricultural areas to surface waters, natural factors such as meteorological and hydrological conditions have a triggering role in processes determining transformations, storage, uptake and losses of nutrients. In order to investigate the effects of meteorological (precipitation and air temperature) and hydrological (runoff) conditions on water quality (losses of total nitrogen (TN) and total phosphorus (TP)) the results of the Agricultural Runoff Monitoring Programme collected at three monitoring sites (Berze, Mellupite, and Vienziemite) during the time period of 1995–2020 were summarized and analysed. The pronounced differences in mean annual air temperature and annual precipitation were observed when the meteorological information representing the periods of twenty years was compared indicating for evidences of climate change. In addition, the relationships between seasonal precipitation and runoff was detected. As affected by the hydrological behaviour the losses of TN and TP in agricultural catchments had large variations depending on the intensity of agricultural production and site location. The changes in seasonal and annual patterns of precipitation, air temperature and runoff may increase the risks of nutrient losses from agricultural catchments in the future.

Low energy building materials based on natural and renewable resources have become popular among customers. The natural occurrence of the raw materials and the idea to move closer to nature with its natural products have brought high interest in hempcrete. Hempcrete is a kind of binder-aggregate material where besides mineral binder, hemp shive aggregate act as a filler. A good technical performance of such composites has been reported before, while the term an ‘advanced material’ for traditional hempcrete lacks some superior properties for civil engineers. This research offers advanced hempcrete-type material where gypsum binder and hemp shives are used as the main components. Additionally, phase change material (PCM) was incorporated into the mixture composition to increase their thermal mass. PCM gives additional thermal heat storage for buildings which makes the building envelope more homogenous regarding thermal stability under outer temperature fluctuations. This could give additional comfort during heating and cooling seasons. Up to 20 wt.% of microencapsulated PCM suspension had been added to the hempcrete mixture composition and heat capacity was calculated and validated with differential scanning calorimetry measurements. Physical and mechanical performance was also evaluated. Results indicate that in the temperature interval from 20 to 30 °C, the heat capacity of hempcrete can be increased to 1901 J/(gK) (by 70.4 %) and it correlates well with theoretical thermal mass calculation. This gives promising results for further development of the material and proves the feasibility of PCM integration in hempcrete.

The European Green Deal sets an ambitious target for Europe to reach climate neutrality by 2050. This commitment will be a challenge, particularly in the context of agriculture, as the sector is responsible for sustainable development and food security. However, one of the primary sources of GHG emissions from the agricultural sector is the treatment of soils using nitrogen fertilizers for crops, especially grain crops. This paper aims to assess the GHG mitigation perspective for soil management in the Baltic States and, in particular, to analyse the grain sector in light of sustainable agriculture and towards climate neutrality. To achieve the aim of the study, the analysis was performed in two parts. Firstly, historical and projected GHG emissions of the Baltic States and mitigation measures on agricultural soil management, including cereal growing were analysed as these emissions show a growing tendency. Thus, the study analyses GHG emission trends, including possible mitigation measures for soil management in the Baltic States. The results indicated that for GHG reduction from agricultural soils, some cost-effective measures could be considered for the future, such as the zero-emissions on-farm machinery and equipment, low or no-tillage, or N-inhibitors on pasture. Secondly, as the GHG emissions from cereals increase, potential alternatives to the use of grain production have been explored to assess the highest possible added value from the product use, thus also contributing to GHG reduction. In this regard, according to scientific literature, a survey was created in the form of a questionnaire based on 32 alternatives, 4 large product groups, and 4 criteria for cereal and straw processing. The respondents were requested to provide an assessment of alternatives, and consequently, a multi-criteria decision analysis (MCDA) was performed using the TOPSIS method. The results reveal the best alternatives from each of the product groups consequently is flour from food products, minerals from a pharmaceutical, biogas from a form of transport and reusable tableware from straw-based products, as a possible cost-effective mitigation measure for soil management from the perspective of the development of sustainable agriculture sector and the transition towards climate neutrality

A heat pump is one of the most popular energy transformation devices to provide the building with the necessary heating and cooling energy during the cold and warm seasons. Air source heat pumps (ASHP) in building heating and/or hot water systems are becoming more and more attractive these days because they can use renewable energy as an energy source instead of fossil fuels and thus contribute to the fight against climate change. By using an evaporator heat exchanger, ASHP takes the low-potential heat from the ambient air and transforms it into higher-potential heat for building heating and/or hot water preparation. The main problem with this type of energy transformer is the freezing of the evaporator at high outdoor humidity and a temperature close to 0° C when the condensed moisture of the ambient turns to frost on the surface of the evaporator heat exchanger. This phenomenon significantly reduces the efficiency (COP) of the ASHP. Thus, its performance strongly depends on the climatic conditions of the environment in which it operates. This study presents a numerical model of the heat pump under investigation developed with the TRNSYS software. The type of heat pump used in TRNSYS has been adjusted according to the heat pump characteristics provided by the manufacturer. The validated model is used to model the heating system of a building in the three Baltic States. Modeling results under different climatic conditions are presented.

In this article, optimal energy consumption in the smart houses is studied considering techno-economic indices and demand side management (DSM) in electrical grids. The optimal energy consumption is implemented based on optimal scheduling of the household appliances than energy price and capacity of demand flexibility in DSM. The proposed approach is considered as two-stage optimization. Using first stage, energy consumption is modified by optimal shifting of the appliances subject to DSM and energy price. Thus, modified energy consumption is taken into accounted in second stage optimization to maximizing the consumers comfort and minimizing operation cost, simultaneously. The optimization process is done in the MATLAB software, in which objectives in second stage are optimized via lp-metric method. Finally, the performance of the proposed modelling is validated as case studies using numerical simulation.

Modern technologies give an opportunity to create a large number of bathymetric maps, but less of them have been focused on processing the water depth data in order to study and estimate the subterranean sources of water object supply. This study aims to create a mechanism for estimating the productivity of subterranean sources of lakes water supply, based on bathymetric survey data. Lake Svitiaz was chosen as the study site as the deepest closed lake of natural origin in Ukraine with an area of 2500 ha and a maximum depth of 58.4 m. To get depth data, ground-based measurements were conducted using an echosounder Lowrance LMS-527cDF. The Lake morphometric changes were investigated, using bathymetric data and Sentinel A, and B data in the digital elevation model (15×15 m). Bathygrahic analysis was performed, allowing selecting areas for further echo-sounding, taking into account complex relief and specific basin forms of the Lake. To develop an appropriate technique for estimating the productivity of subterranean water supply sources, GIS and image (echogram) processing techniques were applied. The research tasks are completed as a technique for detecting ‘tracks’ and a mechanism that is quite effective, particularly for early evaluation of subterranean sources of water supply productivity that can be repeated on any similar water objects.

Biogas-based energy production has become a successful strategy for many livestock farms around the world. However, raw materials production is threatened by a growing uncertainty due to effects of climate change on crops cultivation. The aim of this paper is to propose a tool for the optimal design of the biogas mixture, considering respectively the nutritional needs of livestock and the parameters of the biogas process. Within a context of climate variability, a three-stage Discrete Stochastic Programming (DSP) model is applied in a dairy cattle farm with anaerobic digestion plant. This state-contingent approach (DSP model) considers, as uncertain parameters, the watering needs and the yields of forage and energetic crops. The DSP model is compared with equivalent models of expected values to verify the benefits derived from the explicit inclusion of climatic states. The results showed a remarkable improvement in the efficiency of feedstock management, reflecting in a significant reduction in farm costs (11.75 %) compared to the baseline scenario. Whereas, the comparison between the state-contingent approach and the expected value model, showed only slight benefits (0.02 %). This confirms that the DSP model’s ability to offer a better hedged solution increases when high climate variability affects crop yields and irrigation needs.

Energy communities are paving the way for new cooperation opportunities related to energy consumption and energy production. Individuals unite in energy communities to reduce the costs related to energy consumption. Although previous work has mainly focused on energy exchange inside the community. This work aims to investigate the Pareto-optimal solutions to the transformation of a historical district into an energy community. For energy efficiency and production measure calculation, a system dynamics model is developed. Multiobjective differential evolution optimization method is employed for the evaluation of energy efficiency and production measures with a focus on net present value, self-sufficiency, annual emission reduction, and specific heat consumption. The optimization target functions can be increased at a cost in net present value. Replacement of household appliances and windows enables significant energy demand reductions while maintaining positive net present value. Electricity production from photovoltaic panels offers an additional pathway to increase selfsufficiency share while maintaining positive net present value.

Climate change poses a major challenge to capitalist-oriented societies to restructure their economies and adapt to low-carbon measures that, at first glance, may not be the most economically viable option. Therefore, climate-economy models have become increasingly important in environmental and energy policy in recent years. This study examines recent trends in climate-economy and energy equilibrium research and examines the relationship among the identified key attributes. A bibliometric analysis is used to evaluate scientific publications from the Scopus database that have addressed the relationship between the environment and the economy and have developed climate-economy models. Results show that climate change, emission control, CO2 emissions are strongly linked with economic and social effects, energy policy, renewable energy resources and energy efficiency. Most recent articles focus on photovoltaic system and electricity, energy utilization, economic analysis and sustainable development.

The attributes of cost-effectiveness, reliability, consistency and better understanding, have made researchers prefer studying engine characteristics of IC engines fuelled with alternative fuels/diesel blends with computer simulation compared to conventional experimental study. For the first time, the study attempted to simulate combustion, performance, and emission characteristics of biodiesels from Canola and Sunflower oil domiciled in South Africa. The properties of biodiesel vary from one region to another depending on the local properties of the feedstock used for its production. In this study, a computer model-based C++ was used to evaluate the performance characteristics of biodiesel fuels produced from local South African sunflower and canola oil feedstocks. The developed model was validated using experimental results. The performance characteristics of biodiesel and biodiesel-diesel blends from these oils were tested in a Mercedes Benz OM 364A turbocharged four-stroke, four-cylinder direct ignition industrial diesel engine. Results show similar combustion characteristics for all the tested samples. Diesel shows a higher brake power and higher exhaust gas temperature than all the tested fuel samples. The brake thermal efficiency increases with the amount of biodiesel in the biodiesel-diesel blends. Biodiesel and its diesel blends show higher specific fuel consumption than diesel. In terms of emissions, nitrogen oxide emission was higher for biodiesel and its blends with diesel compared with diesel while smoke emission from biodiesel and its diesel blends was lower compared with diesel.

Heat pumps are increasingly popular in individual buildings and could help to meet expectations of ambitious energy-environmental European goals until 2050. This paper presents the results of energy simulations conducted in TRNSYS for a single-family building depending on its location in selected European cities. For each city, air source heat pump (ASHP) was considered as an energy source for heating and cooling the building, and then an economic analysis was carried out including investment costs of air source heat pump and a comparison of operating costs of ASHP with other alternatives (i.e. gas boiler, oil boiler, or air conditioners). The results of the simulations showed that with the current energy prices the use of air source heat pumps is the most beneficial in temperate warm transitional climate (Krakow). It was also indicated that the implementation of special tariffs (reduced prices) for electricity that supplies renewable energy devices would make heat pumps unmatched as a source of heating and cooling in the residential sector.

As food consumption increases, so does the number of agricultural by-products. That is why it is necessary to find the best possible uses for them, operating by the principles of the bioeconomy. This work aims to gather information on the possibilities of using grain byproducts to develop new products and evaluate which bran products are the most suitable for commercialisation based on economic, environmental, social, and technical factors. Two methods were used in this work: literature review and multi-criteria decision analysis. As a result, 30 products were identified that could be made by using wheat bran, straw, husk, and dust. The products were divided into six groups – packaging materials, building materials, adsorbents, fuel, thermal insulation materials, and chemicals. In multi-criteria decision analysis, it was looked at seven bran products of which the best alternative for further commercialisation is mycelium-based biocomposite.

In this study, a biodiesel blend was developed from the waste cooking oil methyl ester (WCOME) and soya bean oil methyl ester (SBME), namely, the optimum blend of WCOME-SBME (BM100) biodiesel. This biodiesel-biodiesel mixture (hybrid biodiesel) was in turn blended with 15 % of ethanol to give a biodiesel mixture-ethanol blend (BME15). The biodiesel-biodiesel mixture has a better density than the individual biodiesels, SBME had lower viscosity compared to BM100 and WCOME. The presence of ethanol in the hybrid biodiesel blend reduced both kinematic viscosity and the high density of the blend. BM100 also exhibited a better heating value compared to the individual biodiesels. Engine performance and emissions were tested using diesel (D100), WCOME, SBME, BM100, and BME15, and experimental results obtained compared with predicted using Diesel-RK software. The results indicated that at the maximum speed of 2500 rpm, BM100 performed better in terms of brake power (BP), brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), and brake mean effective pressure compared to the individual biodiesels (WCOME and SBME) but marginally poorer to D100. The BTE of BME15 is comparable to BM100. On the other hand, BME15 exhibited better emission characteristics having the lowest NO, particulate matter (PM), and hydrocarbon (HC) emissions compared to D100, WCOME, SBME, and BM100. Overall, when both engine performance and emission are considered BM100 increased engine performance compared to WCOME and SBME while BME15 is more effective in decreasing NO, PM, and HC emissions.

The rapid consumption of resources, as well as the increase in the number of people, has raised awareness of the urgent need to change Europe’s existing methods and attitudes towards the consumption of biological resources in production, processing, storage, reuse and disposal. One of the key principles of the European Green Deal is to make the EU economy sustainable. Achieving this goal requires promoting resource efficiency through the transition to a clean circular economy, restoring biodiversity and, above all, reducing pollution in order to mitigate climate change. The aim of the research is to create and offer bioeconomy opportunities, by demonstrating, analysing, and describing possible solution with the help of various examples. In order to compare different production process methods, which helps to understand which of them best meets the set sustainability criteria, fuzzy cognitive maps (FCM) modelling method was used. Alternatives to 16 bio-products are evaluated using the FCM (fuzzy cognitive maps) method using the Mental Modeller tool, according to four criteria – environmental, economic, social and technological aspects. Obtained results are reliable and objectively reflect the validity of the FCM method, and the use of this type of integrated analysis is appropriate to compare the various alternative production processes considered in the work.

Reed biomass is a widespread resource available in large quantities all over the world, it is fast growing, there is no need for cultivation, harvesting and use des not compete with any other industries. Despite all this, reed is still not widely used and many potential use alternatives have not been researched. Therefore, the aim of this study was to evaluate reed biomass use alternatives for sustainable resource management. A combination of multicriteria analysis methods was used to achieve the goal, which includes assessment of different, mutually incomparable factors, also considering the importance of each of them. Sensitivity analysis was carried out to verify the results. Complex index was developed to evaluate the commercialization potential of each alternative. The best alternatives for reed biomass use are in energy and construction sector, however some innovative products also have promising results. Biorefinery concept is most promising for commercialization of reed biomass in Latvia, however further studies should be carried out to achieve a more comprehensive understanding of reed biomass as a resource for bioeconomy and sustainable development in Latvia.

Capillary heat exchangers are a great alternative to conventional radiators or electric heaters when used with heat pumps due to larger area and therefore a lower working temperature. In this work, we study thermal conditions in a model room using either capillary or conventional heaters. Experimental measurements in a special test building are used to validate and adjust numerical models. The results show that the vertical temperature distribution is similar with both heating systems, but air flow velocities are considerably higher and floor temperature is less uniform in case of radiator heating. Overall, the capillary system provides more uniform thermal conditions.

Pyrolysis is a thermochemical process commonly used for bio-oil, bio-char, and syngas production. It is particularly attractive due to its cost-effectiveness and low environmental impact. Therefore, this study utilizes coffee waste to produce activated carbon in a slow pyrolysis reactor at different reaction temperatures and residence times. The results obtained in this study show that bio-oil yields tend to increase when moderate reaction temperatures and short residence times are used. In contrast, the bio-char yields are higher at low reaction temperatures and long residence times. The Scanning Electron Microscopic (SEM) images of the coffee waste, bio-char, and activated carbon indicate that the pore size of the bio-char tends to decrease due to heating and tends to increase in the area after using ZnCl2 as activating agent. Coffee waste is a suitable feedstock for activating carbon production.

To accommodate the current energy system with the renewable energy source, the concept of micro grid (MG) has been developed. Using such systems, different advantage such as minimization of power loss, operating cost, and emission can be achieved. In this paper, the 24-hour power and heat based MG scheduling is investigated under environmental aspects and economic issues as bi-objective modelling in the presence of demand response (DR) program for decreasing greenhouse gas emission and system operation cost. The investigation of the MG contains energy storage system, boiler and combined heat and power (CHP). For solving the problem, first the Pareto optimal solutions have been obtained by the weighted-sum technique, then the fuzzy satisfying approach has been used to get optimal trade-off result. To confirm the performance of the method, the problem is solved in two-case to demonstrate the effects of DR on MG scheduling.

Hempcrete is a bio-based self-bearing envelope and thermal insulation building material that is becoming more popular nowadays and has a low environmental impact, especially CO₂ emissions. This study looks for solutions for hempcrete printing using a custom-built gantry type 3D printer typically used for concrete 3D printing. Preliminary research shows that hempcrete can be printed at a relatively low density of 660 kg/m³ and achieve an adequate buildability and compressive strength for printing individual wall elements. At this density, hempcrete has a thermal conductivity of 0.133 W/(m·K), unable to provide the adequate thermal resistance at average wall thickness, so high-density hempcrete should be printed as an outer wall shell (similar to Contour Crafting) and the middle filled with lower density thermal insulation hempcrete. By calculating the CO₂ emissions of such printed 400–620 mm thick walls, it was found that they absorb from 1.21 to 16.7 kg of CO₂ per m², thus, such material could reduce the negative environmental impact of the construction industry while improving its productivity through 3D printing.

Jordan and many countries unfortunately have no up-to-date reliable data on the share of electrical energy consumption by end-use in its residential buildings. Therefore, to determine the share in Jordan’s middle district, detailed data was completed for around 350 buildings. The participants in this survey were engineering students in their final year of an energy auditing course in the German Jordanian University. The data were used to determine the primary share of electrical energy end-use in residential buildings. These data, the first of their kind in Jordan, were recorded by trained participants and are essential for the adoption of appropriate future energy efficiency programs in Jordan. These shares of electrical energy consumption by end use in residential buildings in Jordan are the first of their kind it is necessary to ensure adequate planning for future energy efficiency programs in Jordan and this will enable policymakers to support certain technologies and implement large-scale energy efficiency programs in the residential sector.

The 30 January 2020 the World Health Organization declared the beginning of a global pandemic emergency. Italy was among the first European Countries to be severely impacted by the COVID-19 virus. This short communication describes the organisation of a project investigating different responses to the pandemics, studying the assessment of local and national Health Systems resilience to a biologic hazard such is a Coronavirus. Preliminary results highlighted a fragmented response to the epidemics across the Italian territory probably connected to different public health policies or local emergency management models. The implementation of a Multi-Criteria Decision Analysis is provided to study which are the main important indicators to be considered in the pandemic management. The analysis highlights the successful and effective measures for pandemic planning considering different systems: health, economic, political, socio-psychological, demographic, and emergency.

The spatiotemporal variability of vegetation in the Middle East was investigated for the period 2001–2019 using the Moderate Resolution Imaging Spectroradiometer (MODIS) 16-day/500 m composites of the Normalized Difference Vegetation Index (NDVI; MOD13A1). The results reveal a strong increase in NDVI coverage in the Middle East during the study period (R = 0.75, p-value = 0.05). In Egypt, the annual coverage exhibits the strongest positive trend (R = 0.99, p-value = 0.05). In Turkey, both the vegetation coverage and density increased from 2001 to 2019, which can be attributed to the construction of some of the biggest dams in the Middle East, such as the Atatürk and Ilisu dams. Significant increases in the annual coverage and maximum and average NDVI in Saudi Arabia are due to farming in the northern part of the country for which groundwater and desalinated seawater are used. The results of this study suggest that one of the main factors affecting vegetation coverage in the Middle East are governmental policies. These policies could lead to an increase in vegetation coverage in some countries such as Egypt, Saudi Arabia, Qatar, Kuwait, Iran, and Turkey.

Climate change, including the efficient management of CO₂ emissions, is considered a significant environmental challenge today. Carbon dioxide is still considered an undesirable by-product that must be eliminated. However, it can be turned into a source of income. By using the latest technologies of CO₂ capturing and/or utilization, valuable products with high added value can be created. For more effective analysis of the opportunities to use CO₂ in Latvia, it is necessary to find out the opinion of both the public and the industrial sector. The prospects of such technologies in the local market soon depend on the desire and opportunities of the market to turn waste into a profitable resource. This paper aims to determine the Latvian manufacturer’s and society’s willingness to pay and make changes in CO₂ utilization. The analysis of the conducted survey will give an insight into the opinion of these significant market players in Latvian case.

In the present study, calcined phosphate rock was used as a heterogeneous catalyst for biodiesel production from waste cooking oil (WCO). Response surface methodology was used to optimize and determine the significant process variables that affected the experiment. A 5-level-4 factor Central composite design consisting of 30 experiments was used to develop a quadratic polynomial model. The following parameters were optimized, namely, reaction temperature (40–90 °C), catalyst to oil weight ratio (1–5 %), reaction time (40–120 min), and methanol to oil ratio (10:1–18:1). Maximum biodiesel yield of 96.07 % was obtained through numerical optimization at reaction temperature 62.63 °C, catalyst to oil weight ratio of 3.32 %, reaction time 79.07 min, and alcohol to oil ratio 14.79:1. Fourier transform Infrared Spectra (FTIR) analysis was used to characterize the phosphate rock in its raw form, after calcination at 1000 °C and after the first and the fourth reuse cycle. According to the American society for testing and material (ASTM D6751), the fuel properties such as kinematic viscosity, pour point, cloud point, and density were measured and were found to be within the stipulated range.

The article outlines the problem of accumulation of short-fibered waste generated during chipboard sawing. Intense impact on the material determines a high level of technological availability of wood waste. The research objective is to create magnesia composite materials for various purposes based on chipboard processing waste. Moulding sands containing caustic magnesite, fly ash, aluminosilicate ash microsphere, wood waste and magnesium chloride solution have been studied. Change in the ratio of moulding sands’ components provided production of finely dispersed composite material, and granules of cylindrical and spherical shapes. Composite materials of coarse-pored structure have been developed on the basis of magnesia granules and hybrid magnesia-ash binder. Combination of layers of finely dispersed and coarse-pored materials has been proposed to form composites of variotropic structure with density 780–840 kg/m³ and strength 9.7–11.9 MPa. Combined structures’ stability is achieved due to the high adhesive ability of magnesia binders and genetic commonality of various layers.

Yeast Single-Cell Proteins (SCP) production using various agro-industrial byproducts and wastes have significant potential as an alternative to the soy meal, and fish meal protein used for livestock and aquaculture feeds. The use of organic wastes as a substrate in the fermentation processes can be accepted as one of the solutions to reduce the total price of the culture and an environmentally friendlier method of removing these residues. This review article focuses on the yeast biomass yield and protein content increase strategies, which is impossible without understanding metabolic pathways and switching mechanisms. The present work discusses optimization strategies for protein-enriched yeast biomass production, such as fermentation medium composition, including a selection of carbon and nitrogen sources and their ratio, supplemented trace elements, and cultivation conditions such as pH, temperature, time of cultivation, and inoculum size. This review summarizes the theoretical knowledge and experimental results of other researchers that provide an overview of the achievements of the last decades in the production of SCP.

Safflower is currently primarily cultivated as an industrial crop for its oil, which is used for food and industrial purposes, while the by-products can be used for animal feeding. Traditionally cultivated in the Mediterranean area, it was abandoned in the past for other oil crops, such as sunflower. However, it is now returning to be interesting due to its adaptability to low-input cultivation practices, especially when sown in autumn. The main aim of this study is to present a Life Cycle Inventory of safflower grown in a Southern European country, i.e. Italy, based on primary data on agricultural practices used in this country. The study was carried out following ISO 14040 and ISO 14044. Data were collected from experimental fields of the University of Perugia, to ensure a specific and accurate data collection for the definition of the complete supply chain. The reference unit of this study was defined as 1 ha. The stages from raw materials production to seed harvesting were considered. The data presented will be useful to increase the existing knowledge of safflower production in other Mediterranean countries.

The economic cultural heritages are exposed to several natural and nowadays biological hazards, which, in addition to causing potential structural damage, can lead to severe loss deriving from financial non-incomes. The paper aims to highlight the role of insurance in mitigating financial damages and losses, specifically explaining the key role of insurance in mitigating biological hazards like Covid-19. The paper is part of broader research by the authors and uses the assumptions and results already obtained previously in the context of the case study relating to the asset of Villa Adriana and Villa D’Este.

The software market for computerization of modelling and design processes of mining enterprises is represented by American, Australian and Russian solutions, which increases the dependence of Kazakhstani enterprises on third-party developers. Kazakhstani cloud service, scalable according to selected solutions, allows not only to reduce dependence on exported solutions, but also to better adapt solutions to regulatory and legislative documents. At the same time, the promotion of both the service itself and its individual solutions is associated with a number of problems. A marketing strategy for promoting an EIA solution for a software product will allow you to focus on promoting both the entire cloud system and the EIA solution, conquering your market segment, and increasing competitiveness. The consequences of open pit mining may not be entirely favourable when it comes to its social and environmental impacts. This study presents a strategy for promoting a program module for environmental impact assessment (EIA) of open pit mines. The aim of the study is to develop a marketing strategy for promoting the EIA subsystem of the 3DCAREER web application in the context of the globalization of the world economy. Promotion of the module for environmental assessment of the impact of open pits on the extraction of common minerals on the environment to optimize calculations for assessing the impact of open pits in dynamically changing environmental conditions of the enterprise will minimize negative environmental impacts.

In the light of the Green Deal and its ‘Farm to Fork’ and ‘Biodiversity’ strategies, the EU aims to find new ways to decrease GHG emissions through the EU Carbon Farming initiative stating that farming practices that remove CO₂ from the atmosphere should be rewarded in line with the development of new EU business models. The Carbon farming initiative is a new approach and concludes that carbon farming can significantly contribute to climate change mitigation. As European Commission acknowledges that carbon farming is in its infancy and there is a lot to be addressed, in the years towards 2030, result-based carbon farming plots and schemes should be settled by the Member States and local governments; therefore, the existing solutions for reducing emissions through improved farming practices should be defined for each region. The research identifies carbon farming solutions in the agriculture sector – minimal/zero tillage, carbon sequestration in soils, biogas and biomethane production, perennial plant growing, and agroforestry and described.

The ever-increasing amount of greenhouse gas emissions are forcing countries and the industrial sector in particular to develop ways to improve the manufacturing industry and reduce the amount of emissions created in compliance with the requirements of the European Green Deal initiative. However, all modifications must be under local laws and European directives. The purpose of this work is to analyse existing laws, regulations, and directives, both local and European, to identify limiting factors and factors that contribute to a more active introduction of systems for capturing, using, and reducing the amount of carbon dioxide created in production processes. The results of this analysis will determine the strengths and weaknesses of the local manufacturing sector and its ability to meet evertightening requirements.

Shared electric micromobility has been becoming increasingly popular during last few years, especially in the context of Covid-19 and its impact on public transportation. Because of the electric propulsion, electric scooters are considered as potentially one of the ways how to decrease CO₂ emissions in urban transportation sector. This article examines the electric scooter trip data obtained during 2021 scooter season in Riga city. The data analysis shows similarities between scooter trips in Riga and other cities, most notably the hourly trip distribution. There are differences however in many aspects, like average trip distance and duration; the largest difference being the slow average scooter trip speed in Riga, (5.4 km/h) which is comparable to fast walking. The observed significant variance between the trips indicates, that a systematic and holistic approach will be needed to use the scooter trip data making decisions about urban transportation and not relying on average trip data values. The findings from this article will add to understanding of urban transportation in North-Eastern Europe.

100 cities in Europe have committed to being pioneers and achieving climate neutrality by 2030. It is crucial to start with the decarbonization of cities because, although they cover only 3 % of the Earth’s land, they produce 72 % of all greenhouse gas emissions. This paper contributes to the city decarbonization research but on a smaller scale. We study the decarbonization potential of a university campus. It is a unique part of a larger urban area. It represents a cross-section of the population of different socio-economic backgrounds and ages, generating irregular schedules and constant movements of people and goods throughout the day. Riga Technical University is one of the pioneer universities in Latvia that has decided to achieve climate neutrality by 2030. This study aims to provide a qualitative review of the potential for improvements and describe the preliminary CO2 simulation model that includes Scope 1, Scope 2, and Scope 3 emissions. A particular challenge is the Scope 3 emissions, which focus on changing user habits. A survey of Riga Technical University students and employees was developed and conducted to analyse the most effective solutions for this type of emission. Survey results and future work recommendations are presented together with the model outline.

The use of green roofs is demonstrated to improve the energy performance of buildings, increase biodiversity, reduce environmental impacts of urban areas, and mitigate climate change phenomena. Their use on a large scale is desirable in the coming years. Still, the choice of the most suitable green roof design solution should also consider the impacts of their production. Within this study, the Life Cycle Assessment methodology was used to evaluate the environmental impact of a particular typology of soil-less green roofs ideated by an Italian company. In this lightweight green roof, the growing medium is replaced by recycled felt layers, filtration is guaranteed by geotextile, and a closed-loop sub-irrigation system fertilises the pre-growth lawn placed on the top. The extremely low weight of this system suggests an optimal use in building retrofitting scenarios, but its environmental implication was not known. The environmental impact of this product has been assessed with an attributional cradle-to-gate approach through four different methodologies (ReCiPe midpoint and endpoint H V1.1, Ecological footprint V1.01, and IPCC 2013 GWP 100y V1.0) using the ecoinvent v3, Agri-footprint 1.0, and ELCD database on the SimaPro 8.4.4.0 software. The IPCC method has shown a Global Warming Potential of 7.66 kg of CO2 eq. for 1 m² of Pratotetto® green roof; however, the reuse of waste materials from the textile industry must be considered.

In this paper, phosphate rock has been utilized beyond its traditional role as a raw material for fertilizer production to a new potential role as a heterogeneous base catalyst for biodiesel production. The rock was thermally modified through calcination at 900 °C for 8 hrs. One factor at a time experimental design was used to vary the operating conditions of time (30–150 min), temperature (40 °C–80 °C,) catalyst concentration (1–5 wt%), and methanol to oil ratio (10–50 wt%). It was established that the optimum production conditions for maximum biodiesel yield of 93 % using this novel catalyst was achieved at reaction time 90 min, reaction temperature 60 °C, catalyst concentration 3wt% and methanol to oil weight ratio of 30 wt%. The synthesized biodiesel was compared with the raw waste oil using Fourier transform infrared spectroscopy (FTIR) to determine the efficiency of conversion from this catalyst. The catalyst modification after calcination was also analysed using this spectroscopic technique to confirm any changes in the functional groups. Biodiesel’s chemical and physical properties were measured based on the American Society for Testing and Materials (ASTM) international standards for biodiesel.

There are various environmental risks in both the construction and operation phases of huge civil projects such as dam construction. As a result, it is critical to implement appropriate risk control and risk mitigation measures before the initiation of the activities posed by these schemes. The goal of this research is to identify and categorize the environmental risks posed by the Amirkabir Dam during its construction and operation phases. After identifying the risks, the risk factors were prioritized using the FMEA method, with the risks being ranked according to their severity, probability of occurrence, and ability to detect. The study’s findings revealed that the highest risk in the dam construction stage is associated with road construction and vehicle exhaust gases (RPNs of 280 and 252, respectively), and the highest risk in the operation phase is associated with borrow area overuse (erosion and sediment downstream of the dam) (RPN of 280).

Even though the development of renewable energy technologies has been one of the most discussed and research-rich fields of science, and there are many practical and convincing technologies in the field of renewable energy, the path taken by society to shift from the use of non-renewable energy sources to the use of renewable ones has often been slow and unclear. Renewable energy technologies have undergone many improvements. There are several successful and promising examples where installing renewable energy technologies has paid off financially and improved the environment and quality of life. Nevertheless, fossil fuel still dominates or makes up a large proportion of energy production. The research simulates existing, planned, and potential policies to assess the best way to integrate renewable and local energy resources into the energy system by 2030 and in the long term. Policy analysis is carried out for several possible combinations of support measures to assess if it is possible to achieve the set targets in the National and Climate plan by 2030 and reach Climate neutrality by 2050. Such an approach makes it possible to assess the impact of existing policies that create synergies or undesirable side effects and whether they maximize the return on investment from a socio-economic and environmental point of view. In addition, a risk analysis and impact assessment of the proposed policy scenarios are carried out using multi-criteria analysis.

The last decade in particular has seen prosperity in global challenges. Traditional industry leaders have to compete with the challenges of the new generation in emerging markets. Although the European market is competitively mature, the prosperity in global challenges makes it necessary to defend the domestic market as well as to pursue growth opportunities in emerging markets. Analyzing the trends, a comparison of the US and Chinese innovation commercialization policies from a customer perspective with Europe was distinguished. The main difference is Europe's narrowly defined customer segment, companies do not adapt to customer micro-segments with non-matching product and service requirements, because individual attraction strategies must be implemented for each branch, which increase the difficulty to draw potential global clients. The aim of this work is to analyze the US and Chinese innovation commercialization process policies from a customer perspective to gain an insight into the improvement of European national policy models. A multi-criteria decision analysis was used to compare the US and European influencing factor criteria, which focuses on customer segmentation, to determine the most influential segment. Data were also collected in the analysis of the success of European commercialization. The focus on the US end-market approach is expected to increase the value of the proximity factor by improving the implementation of European innovation policy in practice.

The household sector has a significant role in the consumption of energy resources and related emissions. The household sector is responsible for around 1/3 of the total energy resource consumption in Latvia. This study aims to determine the level of control measures regarding household boilers by summarising the existing information on legislation and quality labels regulating the efficiency and emissions of household boilers in the EU. The focus is on PM emissions and small-scale heating system regulations in Latvia. The study shows that small-scale biomass heating systems lack proper control measures to limit created emissions. The situation regarding PM emissions is the worst in Latvia, in comparison to the EU and 8 other studied countries.

Snowfall and ice formation on road surface significantly impact the safety of driving conditions. To resolve this, every year salt and de-icing chemicals are sprinkled on roads. However, use of salts and snow ploughing have environmental as well as economical disadvantages. To resolve these problems, hydronic road heating systems are valid alternatives. Heat transfer fluid, i.e. mixture of ethanol and water, is pumped into a tubular circulation system under the asphalt. By this technology, the road and pavements shall stay ice-free even in times of snowfall and temperatures below the freezing point. The system can also be used to cool the asphalt in case of extreme heat, which – besides the heating effect – could also prevent road from damages in extreme summers. This study aims to compare the environmental impact of use of salts and road-heating system in terms of GHG emissions. To assess the environmental impact, an operational road heating system for a ramp in Ingolstadt, Germany, is considered. A cradle-to-grave analysis technique is used to determine the environmental effects based on a life-cycle assessment (LCA) framework. The analysis includes nine components solemnly responsible for hydronic heating of asphalt surface such as local heating pipe, insulation, pumps, and heat meters. Comparison is performed in terms of relative and total impact over 50-year lifetime of three heated ramps having 1989 m² surface area in total. The results show that the asphalt and heating-circuit causes the major fraction (65 %) of overall GHG emissions, with total life-time emissions of 28.10 kg CO2 eq./m² of heated surface. During an operational life of 50 years, road heating systems emit 18 % less CO2 eq./m² as compared to the use of salts.

Chemical products are widely used in our everyday activities. As the availability and accessibility of ecological chemical products increases, the usage of these products should be promoted and encouraged since it is better for the environmental and human health. However, there is a gap between individual perceptions on these products and actual usage, therefore the aim of this study was to compare the knowledge and perceptions on chemical products and their labelling in Latvian adult citizens and whether this knowledge impacts their choices and usage of chemical products. An online survey was used to gather data from 412 respondents (21.8 % (n = 90) men, 78.2 % (n = 322) women, average age 39.5 years, 77.2 % (n = 318) had obtained higher education). 62.2 % (n = 237) of respondents use household chemicals every day: 6.7 % (n = 25) more than five times a day, 25.9 % (n = 99) two to five times a day and 29.6 % (n = 113) at least once a day. Although 78.2 % (n = 257) of respondents indicated that it was important to them that the household chemicals are ‘ecofriendly’, only 7.4 % (n = 28) of them responded that they always purchase eco-labelled chemical products and 60.1 % (n = 229) do it sometimes. Almost a third of respondents (28.9 %, n = 110) have not payed attention whether the product has an eco-label. Survey data also shows that 91.9 % (n = 351) respondents’ choice regarding household chemicals is affected by their previous experience, including product effectiveness, product ‘ecofriendliness’ (62.1 %, n = 237) and product price (59.2 %, n = 226). Many respondents have correctly identified eco-labels, but at the same time, more than a third of respondents (17.9–39.8 %) mistake other labels to be eco-labels as well.

In this paper, a multi objective optimization approach is studied for optimal energy scheduling of the smart autonomous electrical grid with participation of active consumers (ACs) and hydrogen storage system (HSS). The objective functions consist of: 1) minimizing the costs and 2) maximizing reliability. The ACs participation are modelled through demand reduction approach based on offer price to peak demand management. The proposed optimization is solved by epsilon-constraint method and LINMAP decision making strategy. The 21-node test system is employed to analyse the efficiency of the proposed approach at two case studies. The obtained results shown the high effectiveness of smart autonomous electrical grid with participation of ACs and HSS to supply the demand.

The paper considers issues related to the development of technology for the use of spinning waste in the production of cotton yarn. The process of forming a column of cotton fibers with included waste in an improved feeder-hopper of a loosening-scutching unit designed for cleaning from foreign impurities and dust is theoretically analysed. The optimal design parameters of an improved hopper-feeder with perforated walls have been determined depending on the performance of the loosening-scutchingunit. The approximate distribution of the concentration of foreign impurities and dust is determined depending on the technological and design features of the improved hopper-feeder with perforated walls. The optimal technological parameters of the post-treatment of the formed fibrous layer of cotton after the hopper-feeder have been determined.

Climate change and increasing world population call for careful utilization of water and energy sources. Microalgae to treat wastewater in a coupled process to produce biofuels and other value-added products for human consumption are promising solutions. An analysis of culture parameters and cultivation processes is presented as essential to achieve economical sustainability from the algae. Results of the activity of microalgal strains in detoxification of wastewater are compared and discussed, particularly in remediation of nitrogen and phosphorous compounds, heavy metal, pharmaceuticals and personal care products. Phycoremediation mechanisms and culture conditions to obtain optimal microalgal growth are discussed. Finally, valuable products that can be produced by microalgae and ecological problems of untreated wastewater are presented.

This study focuses on designing a massive open online course (MOOC) to enhance students learning about the energy transition process and its connection to climate change in theory and complex dynamic systems. The course ‘Energy transition and climate change’ covers one of the United Nations’ ‘Sustainable development goals’ and is one of twelve MOOCs that will enable a comprehensive education in system thinking and its applications. It shows how system thinking methods and tools can be applied to tackle current and future energy and climate problems. The goal of the MOOC is to introduce users to the internal dynamics of modern energy systems and energy transition toward CO2-neutral energy systems. The target audience of the course is students who study Environmental Engineering, Energy, Systems, or similar program and anyone else interested in insights into the topic. The course builds on previous energy supply and demand models by updating and adapting them to the existing situation. MOOC is designed by the Competency-Based Education (CBE) approach, and a literature review is used in the study to cover theoretical parts of the course. Technology Readiness Level (TRL) methodology describes the main steps of the course model development progress, and testing of MOOCs pilot version on five students is included in the final stage of the study.

During the vegetation period of the years 2020 and 2021 in the experimental field at Agricultural University - Plovdiv it was conducted a physiological study of tomato cultivar (Rugby) with determined growth under the treatment with chemical and organic fertilizers. The aims of the study were to determine the changes in physiological behaviour and productivity of field tomatoes depending on the fertilization and dates of planting. The physiological assessment included the measuring of some parameters of chlorophyll fluorescence and chlorophyll content index. Chlorophyll fluorescence has proved to have the potential to detect abiotic stress effects on photosynthetic efficiency. This technique was used to assess growth intensity in tomato plants (Solanum lycopersicum), grown in different types of fertilizer treatment and planted in three additional dates – 30.04, 07.05 and 14.05 in conditions of ambient heat stress. Results have shown the slight effect of the applied organic fertilizer upon fluorescence parameters but significantly improved chlorophyll content index compared to no treatment variant. Additionally, it was measured higher chlorophyll content index for the second and third planting dates. The highest average yield was calculated for the NPK variant, as the statistically significant differences of the yield between control and fertilization variants were calculated in 2021. It possessed the highest average yield for second planting compared to the third date of planting.

The future of sustainable development is the bioeconomy with both global and local renewable energy solutions. The updated Bioeconomy Strategy and the Green Deal serves as prove of European Commission commitment for transformation towards a sustainable and climate-neutral European Union. This process is characterized with an enormous complexity and should be studied thoroughly for designing transition pathways. Scientifically sound methods can support policymaking in dealing with uncertainty and complexity taking place within definition of transition pathways. This article reviews the existing bioeconomy development models, and presents a novel model, which focus on agriculture – one of the main directions of the national economy. The concept of model is tested within a case study of crop production sector in Latvia. The results of case study show economically viable scenario for added value target set for 2030. In the crop sector, the baseline scenario and three alternative scenarios were analysed. The highest added value and the most advantageous alternative scenario is for fibre powder produced from cereal bran (in the bioeconomy sector, food provides the highest added value).

The transport sector is one of the most polluting sectors in the world and 29.8 % of all greenhouse gas (GHG) emissions in Latvia come from it. Given this sector’s importance, it is surprising that the external costs of transport are often measured only from the air pollution perspective, mainly CO2 emissions and the health effects associated with these emissions. However, other external costs should be considered when calculating the impact of transport. In this paper, external costs dependent on the type of motor and energy used in vehicles are calculated for Latvia’s current passenger car and light commercial vehicle situation. These external costs are compared with different proportions of battery electric vehicles (BEVs) in Latvia’s passenger and light commercial vehicle fleet. In addition, changes in employment associated with changes in the automotive sector are calculated. The results indicate that having a higher BEV proportion in the fleet reduces external costs in almost all sectors and increases job positions available in the automotive sector.

Woody logging residues produced by logging activities are currently an underutilised resource that is mainly burned for energy production or left in the forest to decay, thus releasing CO₂ into the atmosphere. This resource could be used to manufacture long-lasting products and store a significant amount of CO₂, promoting CO₂ valorisation in rural areas. In this study, potential use for logging residues is proposed – the production of low-density wood fibreboard insulation panels. The new material’s potential properties, manufacturing method and combined heat and power (CHP) plant parameters were proposed. The potential climate benefits of the new product were analysed using various biogenic carbon accounting methods. As energy production for manufacturing can be a significant source of emissions, possible energy production scenarios were analysed for manufacturing the product. However, an economically and environmentally viable energy production scenario should be chosen. By conducting a multi-criteria analysis, three possible energy production scenarios were analysed – wood biomass CHP plant, a natural gas CHP plant and a standalone wood biomass combustion plant combined with Solar photo-voltaic (PV) panels. The scenarios were analysed in terms of technological, economic, and environmental performance to determine the best strategy in this case.

The electricity used for charging electric vehicles (EV) must be produced from renewable energy sources to make EV carbon neutral. Solar PV panels installed at fuel stations can provide a noticeable fraction of charging electricity for EV also in countries located in the Northern region. The study aims to assess the potential dynamics of that fraction given a certain growth rate of the number of EV. System dynamics modelling is used as the method and Latvia is chosen as the case. The model contains parts for the calculation of the number of EV, dynamics of charging units and PV panels at fuel stations as well as in other places, the share of PV-produced power, and the resulting reduction of CO2 emissions. Economic factors, i.e. subsidies for EV purchase, investments, and costs of charging are considered in the model. Assessment is based on sensitivity analysis. Results show that the subsidies for the purchase of EV and the price of new EV play a decisive role in the growth rate of EV and the resulting reduction of CO2 emissions from light-duty vehicles.

Valorization of CO2 captured from industrial processes is an important task for reaching climate and energy targets. The presented study addresses the use of CO2 for the production of ethanol, which can be used as a transport fuel. Hydrogen, produced by renewable energy technologies, is combined with CO2 to produce the synthetic fuel, thus making this approach attractive from a climate perspective. Aim of the study was to simulate the dynamics of the development of CO2-to-fuel solution, taking Latvia as the case. System dynamics modelling was used as the method for analysis. The model reflects several important feedbacks, such as relation between the captured CO2 emissions and the share of avoided CO2 emissions in transport due to fuel substitution, as well as investment in new production capacity of the ethanol. Use of avoided CO2 emission costs for funding of research and development (R&D) of the technology and direct subsidies for ethanol production is the analysed institutional aspect. The results show that if 15 % of the industrial CO2 emissions are used for ethanol production then circa 12 % of the transport CO2 emissions can be avoided. The share of avoided transport CO2 emissions are the most sensitive to unit costs of hydrogen production.

Research data produced within the CARIPLO IMAP and Perform Water 2030 projects were processed using the SimaPro software to carry out the Life Cycle Assessment according to ISO 14040-44 of an innovative process of treated effluents’ polishing. The study aims to evaluate the integration of a microalgae culture as a side-stream process into the baseline layout of a wastewater treatment plant to remove nitrogen from the supernatant of sludge centrifugation from an environmental perspective. In particular, the investigated system focuses on using the algal biomass produced as an organic matrix for encapsulating zero-valent iron nanoparticles to be used for the final refinement of the effluent. Zero-valent iron (ZVI) is a reactive metal and an effective reducing agent. It can be used to remove organic and inorganic pollutants (e.g., chlorinated organics, pharmaceuticals, metals, textile dyestuffs). The encapsulation of ZVI by hydrothermal carbonization (HTC) in a carbonaceous matrix allows for overcoming the problems related to its lack of stability, easy aggregation, and difficulty in separating the ZVI nanoparticles from the treated solution. The case study refers to Bresso wastewater treatment plant (Milan province, Northern Italy). The environmental performances of the study were assessed following the Life Cycle Impact Assessment methods IMPACT 2002+. According to the results, the new process integration does not affect the environmental performance of the WWTP, still implying a significant improvement in the removal of metals and micropollutants. In fact, due to the ability of ZVI nanoparticles to remove organic and inorganic pollutants, the outflowing load will be significantly reduced, which will improve the environmental performance of the entire Bresso wastewater treatment plant.

Lake Kisezers is located near the Baltic Sea, the lake has a catchment area of 1903.26 km² with a high potential for anthropogenic impacts both from water quantity and quality perspectives. This research aims to analyse the movement of water mass in Lake Kisezers and determine how to manage and help keep the lake sustainable. Lake Kisezers was selected as the study site, because of water level and flow data availability and hydrological vulnerability. The methodology used in this research is modifiable and different parts of the research can be used for the analysis of water mass movement in other lakes. Lake Kisezers is an example of how to perform an analysis of the hydrological regime. The research territory is complex because it is possible to study how water mass from the Baltic Sea, catchment area, Daugava River, and Riga HPP interact and influence the hydrological regime in Lake Kisezers. The data sets of water level used in this study are available since 1929. Lake Kisezers has a maximum water level change of 3.17 m. The study evaluates how water mass movements can affect the environmental sustainability of the lake. The results from the hydrological regime analysis can be used for further research and territory management in the favor of lake’s environmental quality and economic development. The research tasks are accomplished as the suggestions on how to manage Lake Kisezers in a sustainable manner have been elaborated.

At the end of 2019, the European Commission launched a new growth strategy called ‘The European Green Deal’ (GD), which aims to ‘transform the European Union (EU) into a fair and prosperous society with a modern, resource-efficient a competitive economy with no net greenhouse gas emissions in 2050 and where economic growth is decoupled from resource use’. This study present developed system dynamic (SD) tool for determining bioeconomy development until 2030 and impact of different GD strategy activities on achieved progress. The bioeconomy index the created and used to measure bioeconomy progress for all scenarios. The optimal scenario was identified between reaching climate goals and adding value to the agricultural, forestry and fisheries resources.

Finding the generic hygrothermal properties of historical brick for application in Heat Air and Moisture (HAM) simulation programs such as Delphin, Wufi, etc., is the main objective of this paper. In this paper hygrothermal properties and Delphin simulation results of 40 different historical brick samples from the 17^th to 20^th Century, were used. The clustering results of hygrothermal properties were cross-examined with the results of clustering results of Delphin simulation data. Six and three clusters were found to be optimal, accordingly for Hygrothermal properties and Delphin results data groups. After cross-examination, a total of 9 combined clusters were recognized, with two dominant clusters containing 67.5 % of all samples (30 and 37.5 %), four of the clusters had only one sample in them, and other clusters had two, three, and four samples in them. Additionally, all the resulting clusters were compared with the brick sample groups that were created based on the description of the brick: color, material type, and year of manufacturing.

This study focused on energy saving in energy hub system using smart grid technologies and management of the energy demand. The two-layer energy management is proposed for implementing energy saving. In first layer, energy demand such as electrical, thermal and natural gas are optimized subject to optimal level of the demand at day-ahead. Then, optimized energy demand is applied in second layer to reduction energy generation costs. The optimization of the proposed approach is done by shuffled frog leaping algorithm (SFLA), and results at several case studies to confirmation of the proposed approach are investigated.