Closed BenWinchester closed 1 year ago
NOTE: Once introduced to the PV panels, it will logically make sense to implement this in the PV layers of the PV-T panels as a simultaneous release. In this way, they can be accurately compared. However, this will likely result in potential hotspots forming/high levels of thermal degradation in closed-loop scenarios, especially closed-loop series solar-thermal and PV-T collectors. There is hence potential to optimise across scenario configurations.
PV-T panels are hybrid photovoltaic-thermal panels and, as per their name, they produce both electricity (through photovoltaic cells) and heat (via thermal collection) from the same collector. There is no one single design of a PV-T collector, but there are designs which are more common within the industry. Flat-plate sheet-and-tube collectors were introduced as part of #76 to the dev
branch and are awaiting release as part of 5.1
or 5.2
.
By collecting both heat and electricity from the same area their benefits are twofold:
Once solar-thermal collectors are introduced into CLOVER #94 , there will be the option to introduce series connections with PV-T collectors #92 . The "series" nature of these connections means that a heat-transfer fluid (HTF) flows first through the PV-T collectors and then through the solar-thermal collectors.
By heating the HTF through a larger area of panel, we can potentially achieve higher temperatures whilst also reducing the "half-way temperature" of the HTF when it leaves the PV-T collectors. This could result in
Depending on how the panels are connected, hot spots may form.
"Closed loop" connections have the HTF passing through a heat exchanger, transferring its heat to a hot-water tank, and then passing back through the collectors.
"Direct heating" connections have the HTF being water which is passed through the collectors from a cold-water source to a hot-water source, with no heat exchangers present, and the HTF being the required water.
In closed-loop scenarios, the nature of the series connections means that higher temperatures may be achieved. This may result in the HTF passing back into the PV-T collectors at a higher temperature than in PV-T-only configurations, potentially causing more damage. There is hence scope to, once this thermal degradation has been included, allow for the comparison between different scenarios, either within CLOVER or as a post-analysis script.
Issue
PV-T collectors, introduced as part of #76 to the
dev
branch, are hybrid collectors capable of producing both electricity and heat, in the form of hot water, from a single device. They are a novel technology, and provide several benefits over stand-alone solar-thermal and PV systems, namelyWhilst the above benefits can be listed in a qualitative manner, it is best to include as many of them into the quantitative calculations of CLOVER as possible. The area of the collectors can be easily introduced down the line, and the combined efficiencies are already being calculated. However, the current functionality misses out on one of the key major benefits, that the PV cells' lower temperatures results in both a higher efficiency and reduced likelihood of degradation.
Proposal
run_simulation
functionality. This would enable a direct comparison of the degradation in performance of the PV cells as part of the integrated PV-T collectors as opposed to the stand-alone PV cells and would enable direct comparisons within CLOVER and its outputs.The only alternatives considered to a robust calculation are a non-robust calculation, i.e., making an approximation of this degradation.