This presentation comes from an instructional course of solar thermal water heating commercial systems from the PG&E Pacific Energy Center. It covers issues specific to solar commercial systems, project financing, and site analysis, among other topics.
The presentation looks at a typical solar water heating commercial system as having a solar fraction of 60% solar and 40% backup. Both open loop direct systems and closed loop indirect systems are used in commercial applications. The most often used collector types are batch, flat plate, and evacuated tube, according to the presentation. Solar thermal commercial systems face many unique problems, such as balancing flow, thermal expansion, and tank sizing. The presentation also suggests that well targeted sites will have high water usage, plenty of room for storage, and adequate roof access.
Author: PG&E Pacific Energy Center
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