Each house in the Skinny Project has been upgraded to include a 3.15 kW solar PV array. We installed the panels flat because the small roof makes it very difficult to angle the panels without creating shading. We actually get better efficiency by sacrificing angled exposure to the sun in favor of reduced shading. Helios, our solar partner on this project, did a great job getting these systems up in the short time we allowed them.
Here are some pictures of the panels going on the roof:
Use the comments for any questions or queries.
{ 5 comments… read them below or add one }
I cannot believe you installed the panels flat! Surely that’s going to reduce their efficiency by such a high percentage that it will render them useless. I’m not sure which way they’re oriented (but since they’re flat, you don’t have to have them facing the sun!), but my educated guess is that 1/2 the panels angled probably would yield more power than what you’ve done here at a fraction of the cost.
Srsly, is Helios actually credentialed in any way to install solar panels? Because from what I’m seeing, this is possibly the most wasteful install I’ve seen since witnessing a solar panel in Japan installed facing north in a courtyard obscured by the shadows of surrounding buildings all day long.
I will be very interested in seeing what kind of juice this array set up actually winds up generating. Good luck with that.
Horizontal panels will get significantly dirtier than slanted ones. Slanted ones tend to be self-cleaning when it rains. Did Helios address this potential problem?
What about snow?
Hazel – Sorry about the delay in approving your comment. It was hiding on me.
All – I’m going to call in Chad to answer these questions regarding our choice of flat mounting the panels as he has more expertise in this area. I will say that we put a lot of thought into this before moving forward and that our installer is both experienced and knowledgeable. Chad’s answers should back that up . . . Chad?
Dear Hazel,
I think you might have some of your facts a bit wrong. The overall efficiency of the system is above 87% taking into account orientation, shading, angle and efficiency of the inverter (96%). Mounting panels flat is actually very common and done almost exclusively in major cities where theft is a problems, space is a premium and neighbors concerns are an issue.
Mounting PV panels flat only reduces the efficiency of a system by a few percentage points. The way Helio designed the layout generates the maximum amount of kWh’s possible on these small and tight urban roofs. Mounting them at angles would have created shading and space problems that would have decreased the efficiency below that of laying them flat as well as reducing the amount of total panels that could be mounted on the roof.
I hope this helps clarify your concerns a bit.