Optimal solar panel angle

March 16, 2008

Back in 2002, I was working on getting a PV solar panel system installed on my house.

My initial calculation for the pay-back period was 15 years, due to slightly less-than-optimal roof orientation and some shade from large cedar trees around the house. This was based on the “easy” approach of having a local company handle the entire project, including the rebate.

By paying for consulting to design the system, buying the equipment myself, hiring a contractor to install it, and dealing with the California state rebate program directly, I managed to get the break-even time down to about 7 years. Though at the expense of significant hassle and a few close calls, like the fact that my original inverter couldn’t deal with the (lower) voltage gain from the Kyocera panels I wound up buying.

Solar Panels

But back to the title of this post – while working on the design, I searched the net to see if somebody had a way of calculating the optimal angle for the panels on the roof. I found exactly what I was looking for here. Then I noticed that the author of this page is Charles Landau, somebody I had worked with briefly while consulting at Palm. And then I found out that he lives in Nevada City, about a mile away from my brother-in-law.

Now we’re both members of the Nevada City tech lunch group, so we get to talk about solar panels, environmental testing, and open source projects like his CapROS operating system.