Solar power, the Bay Area, and me

July 5, 2009 12:54 PM

As we will probably end up buying a house in a sun-drenched corner of the San Francisco Bay Area, I'd like to learn more about solar panels.

I'm looking at a traditional photovoltaic, augment-the-grid setup, but feel free to be creative in your recommendations.

What are good solar panel brands? what are brands that I should avoid?

Any particularly good or bad experiences with installers?

Where are the sweet spots in the 3-D graph of wattage / area / cost?

Are there any developments that could change the market significantly in the next few years?

Where can I learn more?

posted by the cake is a pie to home & garden (6 comments total)

A friend of mine who is an SF resident blogged about this recently. Not a dead-on answer, but all I got.
posted by doteatop at 3:02 PM on July 5

This is a good place to start. Also here.
posted by gingerbeer at 3:05 PM on July 5

I have been doing a lot of research here, but I don't have all the answers. I will give you a summary of the pointers and information I have so far.

It's all about kW-hrs. Kilowatt-hours. If you know the wattage of your array and multiply by the hours of sunlight (I'm sure there are other sources) you think you'll be able to take advantage of per day, then you know kW-hrs which you can compare to your utility bill and figure out whether you'll be paying for electricity or whether the electric company will be paying you.

Anyhow, as far as I can tell, there are for main photovoltaic construction solutions in the U.S.
- The older panels (about 190 W / panel which is about 12 W/sq foot)
- The newer panel technology - higher density (about 220 W/panel - typical vendor/installer: SunPower)
- Solar shingles (about 17 W per run - here's a link with pictures and description)
- The newest (I think) printed membrane (5-6 W /sq foot)
- Also up there with newest (I think) metal solar (also by the folks who have the membrane roofs)

To install the more typical panels, you need mounting racks, an inverter and a cut-off circuit that disconnects you from the grid if the grid voltage drops (this keeps linesmen from getting zaps from your array). I don't know about you but I plan to pay a contractor to do the installs. I understand it's doable if you're a DIY type. :)

The solar shingles go in like normal shingles. It's only the exposed part that's the panel.

I don't have a lot of details on the membrane or metal roof from Solar Integrated.

I also don't have a lot of info on cost. It seems like right now the cost of the 220 W panels may be so significantly higher than the 190 W panels that some folks are choosing to go with the older tech. Another thing to factor in is lifespan of the panels. I don't know what the profile is for the other techs I mentioned, but most folks in the industry seem to say that the panels have a 30 year lifespan, so you want to figure long-term cost-benefit information based on that sort of figure.

Also of great importance to the consumer is the tax credit and rebates situation. In Maryland, where I live, the Federal tax credit is applicable until 2016, I think, and there's a Maryland state tax rebate as well that I would qualify for if I installed solar but I understand that Maryland's having trouble making the payouts in a timely manner.

The last big industry developments I'm aware of are the printed solar membrane and the solar shingles. There could always be more improvement in energy density, but I'd be looking for improvements on cost passed down to the consumer, honestly. At this point in my research I've elected to sit back and watch.

One warning is that SunPower has 1) people who Google them and make comments (self-link in my blog where this happened - I was discussing my decision not to finance a solar solution) in blogs that are not entirely helpful if you happen to have a critical opinion 2) people who bother you regularly to see if your situation or decision has changed. So if you don't like that sort of thing, don't drop them a note.
posted by kalessin at 3:24 PM on July 5 [1 favorite has favorites]

Oh I forgot to mention the other tidbit I learned. When you generate solar energy and drop it back in the grid, not only does the electric company pay you per kWhr, but they also pay you for your green energy credits. Your carbon offset. Apparently in many places, that offset is actually worth more than the Watts you're generating and dropping into the grid.
posted by kalessin at 3:28 PM on July 5

Is there any reason for you not to consider solar thermal panels? They tend to be more economic in a direct comparison, though the final analysis will depend on the relative subsidies available in your location, and on the demand you will have for hot water across the year.
posted by biffa at 4:58 PM on July 5

From Ms. Vegetable:

Check out the solar living institute:
http://www.solarliving.org/

They're located in Hopland, CA - not too too far from SF.
posted by a robot made out of meat at 5:06 PM on July 5