The use of a phase-change material in a PV system

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This graphs shows the power output for the 4 panels from 8am till 8pm of the 26th of June. According to it, the panel 4 has the highest power output. It happens as the panel 4 has no insulation or, in other words, has no container and stays cooler than the others during power producing hours. Therefore, it generates more power.

The panel 3, on the other hand, has the highest temperature during power producing hours due to the existence of a container without PCM or water piped inside of it. As a result, its power output is lower than others.

The panel 2 has a slightly bigger power output than the panel 3. This happens because there is water flowing through pipes inside its container so that its temperature will be a little bit lower.

Furthermore, when it comes to the panel 1, there is PCM inside its container and there is also water piped inside of it, both absorbing the panel heat. As a result, panel 1 temperature gets cooler than panel 2 and 3 and therefore has a power output higher than both.

The graph “Panels temperature” in the first item shows, as mentioned before, that the panel 4 gets cooler and the panel 3 gets hotter during power producing hours.

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As the graph above reveals, the electrical efficiency of the 4 panels are very similar. However, as the panel 4 gets cooler and has the highest power output, it is certainly the most electrical efficient. On the other hand, as the panel 3 gets hotter and has the lowest power output, it is the less electrical efficient.

In addition, a closer look the electric efficiencies in the afternoon of the 25th of July makes clearer that the panel 4 is most electrical efficient, followed by the panels 1, 2 and 3, in this order.

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