Now that the solar collectors for my Solar Domestic Hot Water system are on the roof, and the rest of the job is simple plumbing, which I hope to have done this weekend. I am thinking about my next project. I don’t think we will have the money to do it this year, but next year I’d like to put in 2 kW of grid tied photovoltaics.
That is going to be expensive, I know. I looked up the prices today of the panels and the grid tie inverter plus a tracking mount and it was a whopping $14,590.00. The tracking mount is really not needed to make the system work, however, with a tracker you can expect a 25 percent increase in efficiency. Federal and State tax incentives knock that down to around $10,500.00, but even so, that is about a ten year payback.
If the news is to be believed, those prices should start coming down soon because of added capacity in production of both the panels and the raw materials to make them. Something like a 40 percent increase in manufacturing capacity last year alone. I hope that is true for a number of reasons. I will compare prices in the spring and see if they have come down. We do have a long list of other projects, but, perhaps I could take a second job at Lowes or the Home Depot to help pay for it.
One of the really cool things about photovoltaics, small wind turbines and micro hydro turbines is the distributed generation effect. What this means is that instead of having a couple of huge generating plants with long high tension transmission lines bring the power to major population centers, there are many many small generators over a large area connected to the power grid and synchronized together. This means less need for high tension power lines, huge power plants, and all the associated problems. Demand can be met locally and more efficiently than the large power plant model. Transmission of electrical power over any distance is inefficient, the longer the distance, the greater the inefficiency. Its better for local small businesses (installers), better for the environment and in the long run, better for the home owner.
Paul,
How did you weather proof the connection of your panels to the roof? I’m also curious how the plumbing goes from the house up to the roof? Do you insulate the pipes? You’ve got my really thinking about this solar stuff now!
Todd, I under the mounts I used a rubber membrane, then I used roofing cement around the mounts and bolts. I hit it pretty good with the hose yesterday and everything looks good, no pooling water, and the attic stayed dry.
The pipes will have at least R-5 insulation. The pipes are going through the roof with flanges and will be sloped back toward the drainback tank in the basement. I will take lots of pictures while I am working.
I hope the waterproofing works. It seems like roofs are so hard to waterproof penetrations. I think the biggest reason is the extreme temperature changes the roof feels. I hate cutting holes in roofs and trying to keep out the water.