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Study finds that solar panels should be facing west, not south
Face west young solar-leasing homeowner? A recent study conducted in Austin, Texas, challenges the prevailing belief that for optimum electricity generation, solar panels should be oriented toward the south.
Tue, Nov 19, 2013 at 01:37 PM
Umm … whoops?
According to a recent study carried out by scientists at the Pecan Street Research Institute, homeowners living in the northern hemisphere may have been doing it all wrong all along by abiding by the longstanding belief — common sense, really — that solar arrays
should be oriented toward the south for optimum performance. The study, conducted by analyzing 50 PV-equipped homes in Austin, Texas, shows that west
-facing panels actually generate more juice over the course of a day — 2 percent more, to be exact — and are particularly productive during peak demand hours (3 pm to 7 pm in Texas) when power grids are at their most stained and electricity rates are the most expensive.
Overall, the south-facing panels analyzed as part of the study reduced usage during peak demand hours by 54 percent while west-facing panels were capable of reducing usage by 65 percent.
The information could help inform utility rebate programs for rooftop solar panels and demand response programs. Most homes currently have south-facing panels. For the research, Pecan Street paid a premium to participants to induce them to turn their panels westward. If more utilities were to move to dynamic pricing models, where power cost more during days of high peak demand, west-facing panels could potentially be more attractive to certain households with high peak loads.
Sure, a 2 percent jump — 37 percent of total daily electricity use for south-facing panels versus 39 percent of total daily electricity use for west-facing panels — in efficiency is a tiny amount but also one that can add up rather quickly.
Next up for the Pecan Street Research Institute
? A study on the effect that roof pitch has on electricity generation. Considering how the conventional wisdom-defying results of this study turned out, perhaps pitched roofs, which a majority of American homeowners have, may turn out to be more beneficial than flat roofs after.
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