Volume 27 (2023): Issue 1 (January 2023)

District Heating and Cooling (DHC) technology is widely recognised as a promising solution for reducing primary energy consumption and emissions. The 5th Generation District Heating and Cooling (5GDHC) network is the latest DHC concept characterised by low-temperature supply, bi-directional heating network operation, decentralised energy flows, and surplus heat sharing. Unlike the 4th Generation District Heating (4GDH) technology, the 5GDHC technology switched to a consumer/prosumer-oriented perspective. The introduction of 5GDHC solutions requires high investments, an important barrier to further developing DHC systems. Therefore, a novel pricing and business model could include introducing co-owners or energy managers into the system. Three different local market business models for 5GDHC at the community level have been tested. The reverse technical and economic simulation has been used for a feasibility study to determine the resources, business models, and combinations closest to the break-even point with lower costs and higher gains for all involved stakeholders.

Discharge measurement is the base of proper water management. The effective design and operation of hydraulic structures under both normal and extreme flow conditions depend on the quality of hydrological data. Understanding the water system requires consistent and long-term measurement. Despite that, the gauging station network is sparse, and its numbers are declining worldwide. This article aims to draw attention to the possibility of accurate flow measurement using existing hydraulic structures. Flow over a hydraulic structure profile is a physically well-defined phenomenon as the construction shape is fixed and simple compared to river profiles. The discharge can be derived from rating curves, turbine characteristics, and several easily measured variables. That allows continuous discharge measurement. The accuracy is compared with the gauging station on the river. Suitable technical solutions for ensuring and monitoring ecological flow are discussed.

The world’s leading indoor air quality guidelines provide for the identification of certain parameters with a specific limit value based on the latest empirical measurements, however, most of them do not have legal coverage and are voluntary. This leads to unequal assessment of indoor air quality, because there is an identifiable difference between the limit values set out in the various guidelines. And these values would be related to the results obtained during the experimental activities of the application of the specific parameters and the interpretation of their effects on human health. The aim of this IAQ guideline and IAQ certification review was to develop IAQ label for Nordic countries and to find gaps the legislation established by the Latvian government. The development of indoor air quality labels provides an opportunity to maintain and promote the optimal functionality of human physiological processes and the sustainability of the building.

Transport consumes around one-third of Latvia’s final energy demand being the largest sector that produces greenhouse gas emissions. In Latvia, in the year 2019, the share of renewable energy sources in the transport sector was only 4.8 % of the total gross consumption with a target of 7 % of not food-based biofuels by 2030. To tackle climate change problems, one significant task is reducing pollution in the transport sector by substituting fossil with biomass-based fuels. The goal of this study is to develop a methodology for evaluating biofuel production in Latvia considering economic, social, environmental, and technological aspects. A total of 16 specific criteria were selected for biofuel comparison. The methodology is based on a combination of two quantitative approaches, namely Life Cycle Assessment and Multi-Criteria Analysis. The proposed method aims to identify the most sustainable biofuel in Latvia according to a set of specific indicators.

In this paper, bi-level optimization model is proposed for optimal energy trading between microgrids (MGs) and distribution companies (Discos) with consideration of the renewable energies. The first level modelling is maximizing MGs’ profit and the second level is related to maximization of the Discos profit. In proposed system, power trading between MGs and Discos is considered. As well, renewable energies and demand management strategy are modelled in system for optimal energy consumption. The optimization modelling is solved by Particle Swarm Optimization (PSO), and results of the two case studies show optimal solution of prosed strategy in energy optimization.

In this paper, optimal coordination of the demand side under uncertainty of the energy price in energy market is studied. The consumers by demand response programs (DRPs) have optimal role in minimization of the energy generation costs in multiple energy system. The consumers can participate via local generation strategy (LGS) and demand curtailment strategy (DCS). The optimal coordination is considered as two stage optimization, in which minimization of the consumers’ bills is done in first stage. In following, the minimization of the generation costs is performed in second stage optimization. The LGS is taken into accounted through optimal discharging of plug electric vehicles (PEVs). Finally, numerical simulation is implemented to show superiority of the proposed approach to minimization of the energy generation costs.

The operation of the electrical systems is a major problem for electrical companies’ subject to uncertainties threatening. In this study, the optimal management of the energy demand in the electrical distribution grid is done by interval optimization approach under electrical price uncertainty. The management of the energy demand is implemented via incentive-based modelling of the demand response programs (DRPs). The incentive-based modelling as reserve, and based on bid price for reduction of the electrical demand at peak hours is proposed. The interval optimization approach is used for the minimization of the electrical price uncertainty effects. The main objective in the proposed approach is minimizing operation cost; epsilon-constraint method is utilized to solve the problem. Finally, an electrical distribution grid has been used at various case studies to numerical simulation results and positive effects of the proposed modelling under uncertainties.

Biomethanation is a prospective biogas upgrading method to integrate renewable energy grid with existing biogas grid. Biomethane can directly substitute fossil natural gas and be used in all energy sectors. The selection of packing material for the ex-situ biomethanation in biotrickling filter reactors can be based on the physical and chemical characterization of the carrier material. The packing material selected for biotrickling filter reactors supports hydrogenotrophic methanogenic growth and thereby increases the area for H² mass transfer. Chemical components and melting temperature analysis of wood ash material are carried out to determine optimal parameters for producing wood ash filter material. Physical characteristics of new wood ash filter material such as volume-specific surface area (m² m⁻³), the external porosity (vol. %) and bulk density (kg m−3) are carried out to compare this material with other carrier materials that have been used in biotrickling filter reactors before.

South Africa is a carbon-intensive country, with coal dominating the indigenous energy resource base; however, targets have been set to reduce the national carbon emissions. The transition from coal to cleaner sources of energy generation can be encouraged by the administration of new technologies. Hence, the study aims to review research progress on the pyrolysis of water hyacinth as a tool for the smooth transition to low carbon and climate-resilient economy. Water hyacinth is suitable for energy recovery due to its high carbon content and heating value. The outcome shows that pyrolytic products such as liquid, char and non-condensable gas fractions are beneficial. This paper contributes to policy and research deliberations on promoting and adopting pyrolysis technology in addressing South Africa’s energy crisis and water hyacinth invasion.

Microalgae cultivation at biogas plants creates joint benefits for using liquid digestate and exhaust gas from the CHP unit as nutrient and carbon sources for microalgae growing. This circular approach increases biogas production’s sustainability towards a bioeconomy and zero-waste perspective. This study aims to evaluate the potential environmental impacts in connection to a novel microalgae growing technology named Stacked Modular Open Raceway Pond (SMORP) as a side-stream process coupled with centrate and exhaust gases from a biogas plant. A comparative LCA according to ISO 14044 is performed between the innovative SMORP concept at the pilot level and a hypothetical scaled-up system. Primary data for the inventory are directly gathered from the microalgae growing test performed at the biosystems laboratory of the Institute of Energy Systems and Environment of the Riga Technical University. Secondary data are collected from literature mostly in terms of mass and energy balances considering the SMORP pilot project design. The results of the LCA include the main findings both at mid and endpoint categories according to the IMPACT 2002+ method. In addition, a sensitivity analysis for several different parameters has been investigated. Results show the feasibility of the coupled system and the possibility of having benefits once the system is scaled up. Nevertheless, the results show a critical dependency of the environmental performance on the local conditions, potentially affecting too high cultivation costs.

As the volume of textile waste steadily increases, mechanical, chemical and biological technologies for textile waste recovery are evolving. Also, the legal framework of the European Union has stated the commitments for promoting the recycling of textile waste in the Member States. So far, however, no decision-making algorithms have been developed for the selection of products recovered from textile waste. Within the present study, a hybrid multi-criteria decision-making algorithm for evaluating textile waste recovered products has been developed applying seven circular economic criteria – ‘Circular economy approach of the technology’, ‘Added-value potential of final product’, ‘Share of textile waste in total waste feedstock’, ‘Diversity of textile mix suitable for specific technology’, ‘Pre-treatment of waste feedstock’, ‘Recovery potential’ and ‘Maturity of a recovery technology’. The weighting of the criteria was determined by eight waste management experts. The results of the expert-based criteria evaluation show that the most important criteria are ‘Added-value potential of final product’ and ‘Circular economy approach of the technology’. The developed decision-making methodology has been adapted to nine textile waste recovered products – compost, refuse-derived fuel, ethanol, glucose, building insulation material from cement and textile waste mix, building insulation material from denim textile waste, terephthalic acid, recovered cotton and recovered polyester. The multi-criteria, decision-making ranking of the products textile shows that the highest potential for products recovered from textile waste is for glucose and terephthalic acid, while the lowest – for ethanol, compost and refuse-derived fuel.

Epoxy resins are widely used polymers from which a variety of products are derived and applied in many industries. Most epoxy resins are still obtained from mainly fossil feedstocks, such as epichlorohydrin and bisphenol A, which are also highly toxic. Additionally, fossil derived epoxy resin products are forming non-biodegradable waste at their end of life. Recently the number of studies aiming to find solutions and other raw materials for the replacement of fossil derived epoxy resins has increased, showing that bio-based epoxy resins are a promising alternative. An interesting alternative raw material for bio-based epoxy resins is epoxides derived from microorganisms, such as epoxidized microbial oil. This review article explores and compares the latest solutions for the use of microbial oils in the production of bio-based epoxides, outlines the prospects for their future use and points out the shortcomings of these solutions.

Despite the fact that university students have significant potential to influence the future state of the environment, few academic researchers have focused on environmental behaviour among university students in less developed and developing countries. In the extant literature, there is a need to assess the significance of value behaviour norm theory in different ‘private-sphere’ or ‘daily life’ human behaviours. This paper aimed to assess a possible chain effect between individual values, environmental consciousness and personal norms to promote private sphere Pro-Environmental behaviour among university students. (N = 267). Multiple regression analysis results revealed that Altruistic Values (AV), Egoistic Values (EGV), New Ecological Paradigm (NEP), and Ascription of Responsibility (AR) significantly predicted Pro-Environmental Behaviour (PEB). However, Biospheric Values (BV), Awareness of Consequences (AC), and Personal Norm (PPN) do not significantly predict Pro-Environmental Behaviour (PEB). The Value Behaviour Norm Theory (VBN) model explained a significant amount of variance (65.6 %) in predicting Private Sphere Pro-Environmental Behaviour in University Students. Results indicate that University students may benefit from awareness programs on the VBN model which may improve their Pro-Environmental behaviour.

The European honey bee Apis mellifera is the main pollinator for most crops used for human consumption. However, a number of diseases, parasites, pesticides and other factors that generally result in the widely described colony collapse disorder weakens honey bee colonies. In order to maintain the existing honey bee germ lines and facilitate the creation of new disease-resistant lines, it is necessary to ensure consistent breeding work, which would also allow the long-term preservation of the unique germplasm lines. One of the most promising solutions for the preservation of honey bee germplasm is the storage of honey bee drone semen. In recent decades, there has been a renewed interest in the preservation of honey bee drone semen using both cryopreservation and above-freezing storage methods. This review summarizes the latest developments in novel sperm storage technologies and their assessment by sperm quality and queen fertility indicators. Additionally, this article analyses the advantages and disadvantages of the reviewed solutions and outlines directions in which additional research would be needed to develop effective, available and affordable drone semen storage solutions. To the best of the authors' knowledge this is the first review of cryopreservation and above-freezing storage solutions of European honey bee Apis mellifera drone semen in the scientific literature.

To achieve the climate targets set by 2030 and become climate neutral by 2050, each Member State must develop a National Energy and Climate Plan (hereinafter NECP) containing practical and effective measures to achieve the targets. The research sought a connection between the measures or action lines in the Latvian NECP related to agriculture and forestry, the European Green Deal goals and related strategies. The effectiveness of the agricultural and forestry measures defined in the Latvian NECP was evaluated by defining appropriate indicators, an expert survey and a composite sustainability index. The results show that the effectiveness of agricultural and forestry measures is most influenced by quality, financing, and specificity factors. The lowest-scoring measures were specific measures whose impacts cannot be measured and are not explicitly mentioned in the European Green Deal. Therefore, the description of the measures should be more detailed, with specific activities, indicators to be achieved, and amounts and funding sources planned for each activity.

The concept of the new water treatment system was developed. A primary area was defined in which such technology is intended to be used: water treatment in compact flue-gas condensation systems for a low-power wood-fuelled biomass boiler. A prototype operating based on invented technology was built. An experimental plan was developed, and an experimental stand was constructed to determine the prototype’s efficiency. Based on the study’s results, it was concluded that the prototype could operate effectively in the laboratory environment: achievable efficiency is equal on average between 57.84 % and 88.09 % depending on the operating mode. The result is assessed as positive. TRL 3 has been reached.

Global annual textile consumption has doubled in the last two decades and is expected to keep increasing. Since the textile system operates primarily in a linear way, it is highly polluting and creates a lot of waste. But nevertheless, it has a high potential for circularity since most textile products can be recycled or reused. Today most of the waste ends up in landfills, and less than 1 % is recycled back into textiles. This study aims to gather information and evaluate which textile product group has the highest potential for circular economy growth. It covers three main textile product streams: fashion, home, and technical textiles. The groups were compared using fifteen criteria: environmental impact, washes, landfilled waste, recycled waste, origin of fabric, projected lifetime, market demand, production volume, international trade, labour productivity, value added, energy efficiency of production technologies, innovation capacity, employment, and enterprises. Input values have been found for each sustainability indicator by using and mathematically transforming data from the scientific literature. The evaluation method used in this study was multi-criteria decision analysis. The results indicated that the fashion textile group has the most significant potential for circular economy development, mainly because it is the largest textile product stream, and the development of a circular economy could be cost-effective.

The marketability of fish depends on the visual appearance of the fish, so the feed ingredient pigment contributes to the nutritional value and visual appearance of the product. The benefits of a natural pigment derived from microalgae are the ecological benefits, as the culture can fix carbon and release oxygen. The economic aspect is a benefit of synthetic pigments. The Life Cycle Assessment (LCA) method was used to determine the environmental impact of natural and synthetic pigments. The results obtained from the LCA are expressed according to the impact categories defined by the Product Environmental Footprint Category Rules (PEFCR). A sensitivity analysis was also carried out comparing the environmental impacts of electricity generated with hydropower or using a field mix from Norway for the natural pigment. The total single score value for natural pigment is 1.17E+01 mPt and the largest impact is from sodium nitrate and electricity. The sensitivity analysis results for electricity from the country mix is 1.82E+01 mPt. The total single score value for synthetic pigment is 8.24E−01 mPt, with the largest impact from methanol. Synthetic pigments have a lower environmental impact than natural pigments, but a sensitivity analysis shows that the environmental impact can be reduced by choosing an alternative to electricity. It should be noted that the comparison presented represents a general comparison of alternatives, as the input data is derived from a literature review.

Solar collectors are devices that enable the use of solar radiation, e.g., for hot water preparation or space heating. They are playing an increasingly important role in Europe and around the world, mainly due to the easy availability of the sun, as an energy source. The advisability of their use depends on a number of factors, of which climatic conditions are an extremely important one. This paper presents the results of energy simulations of a solar collector-based domestic hot water system for the capitals of five selected Central and Eastern European Countries (CEEC): Riga, Warsaw, Prague, Bratislava, and Zagreb. Using TRNSYS software, a theoretical model of the system was developed and dynamic simulations were carried out for the entire year. The amount of useful energy generated by the flat-plate collectors, their efficiency, as well as the auxiliary energy requirements and the amount of energy needed to meet the load were estimated and compared. The extent to which changing the area of solar collector affects the operation and efficiency of the system for different locations was also analysed. The results showed that in terms of efficiency, the use of solar collectors is most favourable in placed southernmost Croatia and in Slovakia, where it was also achieved the lowest annual auxiliary energy demand. The least favourable location turned out to be Riga. It is also worth noting that regardless of location, the area of solar collector has a significant impact on the efficiency of the entire system.

Harvested wood products (HWP) can play an important role in climate-smart bioeconomic transformation. They contribute to climate change mitigation through two main mechanisms: carbon storage and substitution. Norway has ambitions to strengthen the contribution of its forest sector in climate change mitigation. Ideally, the future production and use of HWPs would increasingly shift towards products with high carbon storage and substitution benefits. We collected data from the literature and, when necessary, supplemented it with our own calculations, on carbon storage and substitution factors of HWPs that seemed relevant in evaluating the climate change mitigation potential in the context of the Norwegian forest sector. There are many uncertainties in the parameters. We identified and examined in more detail some uses of wood for industrial products that offer clear substitution benefits and, in some cases, long-term carbon storage. Wood-based construction materials, textile fibres, and insulation materials are examples of such products that could have high potential in the bioeconomy transformation in Norway.

The share of renewable energy in heat and power generation is expected to increase significantly and reach record levels in the coming decades. As a result, emerging energy storage technologies will be key elements in balancing the energy system. To compensate the variability and non-controllability of seasonally generated renewable energy (RES) (daily fluctuations in solar radiation intensity, wind speed, etc.) development of sufficient energy storage infrastructure in the regions will play a major role in transforming RES supply potential into reality. However, local public authorities that are responsible for creating an enabling policy environment for RES infrastructure development in regions encounter numerous challenges and uncertainties in deploying sufficient energy accumulation that often remain unanswered due to a lack of knowledge and on-site capacity, which in turn significantly hinders the regional path to climate neutrality. In this study, the PESLTE analytical framework and composite index methodology is applied to examine the multidimensional factors that influence the deployment of renewable energy storage technologies in municipalities: political, economic, social, legal, technological, and environmental. Developed model is approbated in a case study in a Latvian municipality where four different alternative energy storage technologies are compared: batteries for electricity storage, thermal energy storage, energy storage in a form of hydrogen, and energy storage in a form of biomethane.

The influence of people on building performance is becoming increasingly significant. Including users’ perspective in decision-making and design processes could help to improve occupants’ well-being and the feasibility of interventions by providing more accurate information about heating preferences for energy models. Furthermore, understanding residents’ level of thermal satisfaction could enable more appropriate measures to be taken to improve the energy efficiency of buildings. This study aims to define an indicator that measures the level of thermal satisfaction of social housing occupants so that it can be contrasted with other methods of analysis of perceived comfort and can be replicated in different building contexts. A way to analyse occupants’ thermal satisfaction is proposed in a quantitative way, measured as the difference of the desired temperature and the perceived indoor temperature. The index was applied to a sample of 283 social housing dwellings in the Basque Country, Spain, with data obtained via surveys that include questions on thermal comfort in winter and households’ characteristics. Furthermore, the indicator was compared to other variables, such as household income and energy expenses, to observe behavioural trends and possible cases of energy vulnerability. The obtained variable provides occupants’ opinion and perception to ensure the suitability of the solutions for improving the energy efficiency of the building and the thermal comfort. It is also possible to apply it to different building typologies and compare the results with other models of perceived thermal comfort.

Numerical optimization methods are used to reduce the operative costs and emissions of domestic houses comprising photovoltaic energy production and battery electrical storage combined with time-variant electricity prices. The modelling of the system comprises the different involved devices, energy flows and their constraints, and an objective function, which parametrizes the object of the optimization. The solution of the optimization problem defines the most adequate charging and discharging strategy of the battery into the future (prediction horizon). Power inverter efficiencies are usually modelled by assuming that they have constant values, and hence, that charging and discharging energy-flows lie on the most probably operating region of the inverter. A more realistic modelling of the power inverter efficiencies should consider a nonlinear parametrization of the efficiency curves. This consideration converts the optimization problem into a nonlinear one. It this paper, we modify a method to solve nonlinear optimization problems means iterations of linear optimization problems. The first iteration uses as seed values the solution of an optimization problem, which considers constant efficiencies of the battery inverter provided by the manufacturer of the battery. With the values of the solution of the optimization problem and with help of measured (dis)charging power curves and the optimized (dis)charging, new values of the efficiencies of the inverter of the battery will be determined, and the optimization problem will be with these values again computed. If a certain number of iterations is achieved or the values of the efficiencies converge, then the process stops.

In recent years, there has been an interest in the study of new methods for the removal of dyes from water due to its large-scale use in different industries, for example, for paper printing, textile, leather, pharmaceutical, food or technological applications. It is estimated that more than 700 thousand tons of about 10 000 different types of dyes are produced annually. Most of them are synthetic origin and can generate adverse effects, for example, teratogenic, mutagenic and carcinogenic action. Dyes are mainly applied in the textile industry, and they are usually classified into anionic (acid dyes), cationic (basic dyes) and non-ionic (disperse dyes) dyes. The direct discharge of dyes into the environment can cause various damages to plants and animals: dyes can block the penetration of sunlight, reduce the photosynthetic efficiency of aquatic plants and ultimately destroy the ecological balance of the aquatic ecosystem. This study determined the adsorption efficiency of congo red, methylene blue, rhodamine B and naphthol green B dyes used in textile industry by using the aerogel – an adsorbent synthesized from paper waste. Total carbon was selected as indicator of dye concentration in solution. An increase in fibre content from 3 % to 5 % contributes to the improvement of adsorption properties. The decrease in congo red concentration after an adsorption process was 31.0 % and 38.0 % respectively; the decrease in methylene blue was 2.49 % and 8.15 %; the decrease in naphthol green B was 28.04 % and 34.14 % and the decrease in rhodamine B was 1.28 % and 4.13 %.

Sustainable development in the agriculture sector can be boosted by integrating a sustainable bioeconomy and transforming renewable resources into added-value products. There are various methods to determine, measure, and compare the extent of sustainability. We promote the bioeconomy concept by utilizing agricultural waste in biopolymers considering the sustainable development in the agriculture sector. This research aims to evaluate biopolymer alternatives based on sustainability criteria and indicators using the integrated multi-criteria decision analysis approach under the sustainability umbrella. We evaluated the PLA, PHA/PHB, starch, protein, and cellulose-based biopolymers. As a result, the cellulose-based biopolymer shows the best performance. The research findings provide valuable information to establish a sustainable pathway for biopolymer production for industries.

As humanity sets its sights on establishing a sustainable and prosperous colony on Mars, the main challenges to be overcome are ensuring a reliable and nutritious food supply for settlers, feedstock for 3D printing, fuel and pharmaceuticals. While various solutions for production of essential products on Mars have been proposed, there is growing interest in the use of microorganisms as the main production units. This scientific review article proposes a novel concept of using single cell oil (SCO) as a versatile feedstock for various applications in a bioregenerative life support system (BLSS) for space missions. The authors suggest using outputs from autotrophic systems, such as cyanobacteria biomass and oxygen, to cultivate SCO-producing microorganisms from the class Labyrinthulomycetes. The produced SCO can be used for food, fuel, 3D printing materials, and pharmaceuticals. This approach can potentially reduce the importance of carbohydrates in space foods, offering various benefits, including a reduction in food weight, simpler, lightweight, more compact bioreactors, launch cost reduction, potentially improved mental and cognitive performance, and reduced fatigue for the crew. The authors also suggest using SCO as the feedstock for the production of 3D printable filaments and resins and as a supplementary fuel source for space colonies. While the concept is hypothetical, the theoretical foundation is solid, and this approach could potentially become an important element required for the establishment of a successful Mars colony.

Businesses willing to reduce their carbon footprint embrace sustainability and positively impact the progress towards achieving climate neutrality. Well-prepared and presented information to the business customer before purchasing can be a strong driver for better decision-making towards less impactful product alternatives. This study presents the development of a tool for packaging products online marketplace that informs customers about the carbon footprint of packaging products and allows them to evaluate which of the select packaging alternatives is most preferable from an environmental perspective. The tool implements a life cycle analysis (LCA) approach, including the stages of raw material extraction, packaging production, and transportation to the customer. The impact assessment in the tool is performed according to Intergovernmental Panel on Climate Change (IPCC) 2021 methodology for assessing greenhouse gas (GHG) emissions based on information obtained from the Ecoinvent database. The final output of carbon footprint calculation is provided with an indicator marking the carbon footprint performance of customer-defined alternatives in a clear, simple, and consistent way. The tool aims to educate customers, foster informed purchasing decisions, and improve the environmental outcomes of their decisions.

This study focuses on economic modelling of the energy consumption in buildings considering controllable appliances scheduling in stand-alone electrical grids. The economic modelling is implemented via coordination of the energy generation of the renewable energies with controllable appliances by using demand shifting strategy (DSS). On the other side, uncertainty and stochastic modelling of the renewable energies are considered in the optimal coordination. Also, optimal coordination is modelled by multi-criteria problems of the technical and economic indices. Solving of the multi-criteria problem is done by fuzzy and augmented epsilon-constraint methods. To investigate the effectiveness of the proposed model, it is applied on a 25-node test system through defining two scenarios. The obtained results show that modelling the optimal coordination to supply the demand of the grid can increase the efficiency of the system.

The energy renovation of buildings is one of the main keys to achieve the decarbonisation objectives of the European Union (EU). In response, the Commission Recommendation (EU) 2019/786 proposed an assessment framework based on Measurable Progress Indicators (MPIs) to assess the decarbonisation. The objective of the study is to analyse the applicability of the MPIs in Spain; for this, the study analyses the viability of the MPIs and carries on the prioritization of the MPIs. Thus, the methodology is developed in three stages: (1) analysis of data availability the viability of each MPI; (2) prioritization of the MPIs by and expert round table (ERT); (3) applicability analysis of the prioritizing MPIs. Firstly, the analysis of viability shows that the data availability and the quality is limited, with many data source entities and big diversity of data features and quality. Secondly, the expert round table prioritized 8 MPIs regarding the EU’s targets in building renovation. Thirdly, the applicability evaluation finds out many barriers but also identifies the key points to launch the MPIs base assessment framework. The study identifies the entities that could likely carry on the data collection and other challenges like the digital building logbook (DBL) or the monitorization towards the efficient assessment of the renovation of the building.

A critical procedure in sustainable building design is that building energy consumption has significant implications for the global energy crisis and climate change. This study compares three simulation software programs for a photovoltaic system on a building’s roof. The low-rise residential buildings in three East Mediterranean cities (Amman, Mafraq, and Aqaba) represent moderate dry–warm, semi-arid, and humid subtropical climate zones were compared using three simulation software programs (IES-VE, Design-Builder, REVIT) for a typical building with PV on the roof and the second scenario without a PV system installed on the roof. This investigation aims to evaluate the shading effect of the PV system on a building’s roof structure by calculating the total heating and cooling loads required to maintain thermal comfort inside the building. The results showed significant discrepancies between the three software for the base building design and the PV system on the roof, with a range of around 50 %. This highlights the importance of evaluating and calibrating different simulation tools and using them with a great deal of caution.

Most agricultural by-products are not recycled or fully utilized. Most of them end up in waste and cause economic, social and environmental problems. Today, much of the byproducts are considered waste, although they can be appropriately recycled to produce new value-added products. By-products have great potential to create, for example, food additives. Many of these byproducts are a source of valuable compounds such as proteins, lipids, starches, trace elements, bioactive compounds and dietary fiber. A wide variety of extraction methods are currently available, but several factors must be considered to determine which of these methods can efficiently and environmentally produce high-value-added products from by-products. The article examines, summarizes and compares various extraction methods, as well as products that are currently obtained using specific methods.

Using algae metabolites is considered a current and innovative topic of interest. Among the various applying sectors such as food, manufacturing, and environment, these organisms are also characterized by a high therapeutic potential. The influence of biotic and abiotic factors allows the production of different bioactive compounds, such as carbohydrates, polyphenols, proteins, vitamins, sterols, fatty acids and many others. The algal biomass is investigated to discover and develop new possible therapies and nowadays different properties have been determined, like antioxidant, antiviral, antimicrobial, anti-inflammatory, antidiabetic. Typical examples include the application of algae in diabetes mellitus, which is a disease that is continually spreading throughout Europe and the world. Numerous trials are currently underway to develop innovative and effective treatments, as well as several algae are being investigated in order to gain a deeper understanding of this pathology. In recent studies it has been demonstrated that metabolites such as polyphenols, polysaccharides and pigments, by their inhibitory activity, are capable of reducing blood glucose levels and increasing the amount of insulin.

This study aims to evaluate numerically the influence of wind speed on scales of environmental harmful consequences caused by accidentally spilled toxic liquid evaporated from the surface of a free-form outlined spill spot. A coupled problem of the gas-dynamic movement of a toxic air-mixture cloud in the atmosphere’s surface layer under the influence of wind and a negative toxic inhalation impact on a human in an accident zone is solved by means of mathematical modelling and computer experiment. A three-dimensional non-stationary mathematical model of the turbulent movement of a gas-air mixture is used for obtaining distribution of relative mass concentration of toxic gas impurities in time and space. A probabilistic impact model based on using a modernized probit analysis method is used to obtain fields of conditional probability of a fatal human injury resulting from toxic gas inhalation. This technique allows environmental safety experts assessing the scale of considered type technogenic accident consequences numerically depending on wind speed conditions and elaborating the means to mitigate them to acceptable levels.

Wood charcoal is a sustainable, renewable, and environmentally friendly material with the use that the acoustic device can produce. Charcoal made of wood waste materials allows for improving indoor acoustical quality. Therefore, this objective of the article is to investigate the sound scattering coefficients of QRD with the perforation ratio of oak wood charcoal elements. Sound scattering coefficient calculated with the measurement of the reverberation time in the reverberation chamber. The calculation results of the scattering coefficient show the growth of scattering in the frequencies - the highest value reached 0.88 (diffuser N7 with charcoal). The effectiveness of diffusers to diffuse sound waves increases as the number of wells grows. The diffuser with 80 % charcoal elements showed a higher scattering coefficient compared to the diffuser without charcoal elements.