<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>In recent years, the demand for energy-efficient technological solutions in the building sector has risen significantly worldwide. The exploitation of phase change material as a medium for thermal energy storage in building envelopes has increased due to its superior properties. There is still a knowledge gap to cover in the way to the effective solar thermal energy storage in the building envelope – to enhance the heat transfer, to reduce the heat loss, etc. This paper deals with the optimisation of heat transfer using a solar concentrator (Fresnel lens). This study examines the effect of Fresnel lens focal point location on heat transfer in a dynamic solar facade prototype that stores thermal energy in phase change material. Nine different setups (solar façade compositions) were tested in the laboratory – two parameters with three alternatives each. Testing conditions simulate the relevant Northern Europe climate. By changing the air gap configuration and location of the Fresnel lens focal point, the heat transfer to phase change material was observed by measuring temperatures in the phase change material container using five thermocouples. The results show the improved thermal performance in test modules with larger cone diameter by 7.2 % and Fresnel lens focal point positioning closer to the back of the phase change material container by 5.4 %.</p>
</abstract>

In recent years, the demand for energy-efficient technological solutions in the building sector has risen significantly worldwide. The exploitation of phase change material as a medium for thermal energy storage in building envelopes has increased due to its superior properties. There is still a knowledge gap to cover in the way to the effective solar thermal energy storage in the building envelope – to enhance the heat transfer, to reduce the heat loss, etc. This paper deals with the optimisation of heat transfer using a solar concentrator (Fresnel lens). This study examines the effect of Fresnel lens focal point location on heat transfer in a dynamic solar facade prototype that stores thermal energy in phase change material. Nine different setups (solar façade compositions) were tested in the laboratory – two parameters with three alternatives each. Testing conditions simulate the relevant Northern Europe climate. By changing the air gap configuration and location of the Fresnel lens focal point, the heat transfer to phase change material was observed by measuring temperatures in the phase change material container using five thermocouples. The results show the improved thermal performance in test modules with larger cone diameter by 7.2 % and Fresnel lens focal point positioning closer to the back of the phase change material container by 5.4 %.

The Effect of Fresnel Lens Focal Point Location on Heat Transfer in Phase Change Material (PCM) Enhanced Dynamic Solar Facade

Environmental and Climate Technologies

This work is licensed under the Creative Commons Attribution 4.0 International License.

In recent years, the demand for energy-efficient technological solutions in the building sector has risen significantly worldwide. The exploitation of phase...

The Effect of Fresnel Lens Focal Point Location on Heat Transfer in Phase Change Material (PCM) Enhanced Dynamic Solar Facade

Published Online: Dec 16, 2022

Page range: 1268 - 1278

DOI: https://doi.org/10.2478/rtuect-2022-0096

Keywords
Building envelope, melting temperature, solar thermal energy storage, latent heat, small-scale dynamic solar module

© 2022 Jānis Narbuts et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

The Effect of Fresnel Lens Focal Point Location on Heat Transfer in Phase Change Material (PCM) Enhanced Dynamic Solar Facade

Published Online: Dec 16, 2022

Page range: 1268 - 1278

DOI: https://doi.org/10.2478/rtuect-2022-0096

KeywordsBuilding envelope, melting temperature, solar thermal energy storage, latent heat, small-scale dynamic solar module

© 2022 Jānis Narbuts et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
Building envelope, melting temperature, solar thermal energy storage, latent heat, small-scale dynamic solar module