We all know that photovoltaic glass will generate part of the electricity when it absorbs solar radiation, but how to remove this part of the electricity when calculating? If not removed, it may be added to the indoor load as absorbed heat, which may lead to inaccurate simulation results. So I’m looking for some methods in the paper. When i see a paper that DOI: 10.1002/pip.2727, i find out he built photovoltaic glass by a method:
The “integrated surface outside face” mode was used in this study, where the solar cell temperature refers to the outside surface temperature of the PV module. When calculating the heat-transfer and temperature distribution, the energy generated by the PV module was removed from the heat transfer balance equations.
But I don’t know how to use “integrated surface outside face” mode and remove the energy generated by the PV. can you help me @chris .
this paper,The method I’m using now is to export its idf file from HB and put it into energyplus to set up the Generator; Integrated Photovoltaic, then I is to use heattransferintergrationmode Settings. Because according to the energyplus reference, he told me that if you want to couple thermoelectric models you need to set up integrated. However, when I set up this post-simulation, he told me that internal heat source should be added to the surface, but the window is not allowed to add source/sink in enrgyplus. So now I’m totally freaking out about this, so I was wondering if you have any other ways to decouple the thermoelectric model of the window.
Hi @shuo, it’s probably too late, but in case it is not, here is what I found out in my research:
The heat transfer integration mode is only appliccable for opaque surfaces, as you already said. Unfortunately this is not so clear from the E+ documentation. This paper has confirmed that. The researchers found that there was no difference in PV Cell temperature / Window Surface Temperature when enabling the heat transfer integration.
In this paper, the researchers therefore followed another approach. They added the efficiency of the STPV laminate to the solar reflection of the glazing, since this would remove the part of the energy that is transformed into electricity from the absorptance right?
Now, one “simplified” approach could be to solve the heat balance equation in order to determine the PV Cell temperature in the laminate and determine the effective efficiency based on the cell temperature (efficiency * (1+temperature coefficient*(Cell Temperature - 25°C)) and probably other modifiers (AOI). That allows the calculation of the effective reflectance (which consequently changes as the efficiency changes). This effective reflectance could be used in order to select different glazing materials that correspond to this reflectance and the construction could be changed with the help of EMS actuators that change the construction state based on the effective reflectance.
The heat balance equations used in E+ however are not applicable 100% for STPV windows as lined out in the engineering reference. Therefore the approach in itself would be consistent, but the PV Cell temperature probably won’t match real life STPV cell temperatures. However, I think for the moment this could be a simplified approach to overcome this limitation in energyplus.
