Monday, September 13, 2010

Buzz's Solar Panels

One morning in mid-July I was walking my dog Wrangler around the neighborhood when I noticed one of my neighbors was getting solar panels on their house.

Solar panel systems can be designed for different amounts of energy. My neighbor's system was designed to take care of 101% of their energy usage. The goal for them is to never have another electric bill. Since the cost of electricity will no doubt go up, if their energy usage stays about the same, they could end up saving thousands per year when the system is paid for.

I got the installer's card, talked it over with my wife, and called them to make an appointment to see what the deal was. Here's how it works:

All of the companies work about the same way: the company comes out and examines your energy usage over the last 13 months. It's all about averages. Because there's no battery, and because the system won't work at night (no sun), you want to generate all the energy you'll use during the day. The excess power is transferred back to the utility, and then fed back to you when you need it (at night, for example). You're never "off the grid," and it's evidently possible to have a negative electric bill if you don't use as much energy as you generate.

The solar system generates DC power which must be converted to AC to use in the house. They use what's called an inverter to do that.

The cost on paper seems high, but there are some incentives for going solar. My utility, Tucson Electric Power, pays a rebate per watt generated by the system. In my case, the rebate works out to about $22,500. Then there's a 30% federal tax credit and a $1000 Arizona state credit for renewable energy. These help reduce the system's cost a lot. They can finance the rest for 0% interest for a year, which gives you time to collect the federal and state tax credits when you file your taxes.

We visited with more than one company and wound up going with the same company that our neighbor had used, mostly because her experience was very good and we had seen their completed work.

The system they designed for us will cover almost all of the south-facing roof of our house. We'll be getting 36 solar panels. As it turns out, our house is nearly perfectly aligned with true south, which is the direction for maximum solar efficiency. This is different from magnetic south.

After the contract is signed, the company files for the necessary permits, the utility rebate, and gets approval from the Homeowners Association. I had to call DirecTV to have my dish lowered, so it wouldn't cast a shadow on the roof. Shadows = bad for solar electricity.

Today we got the call that the TEP rebate was approved, and they scheduled our installation for early October.

I'll update again as soon as there's something new to add!

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