I live in Pittsburgh. I’m interested in putting in solar panels to help with the utility bills. I have gas-heated hot water radiators that get rather expensive in this big house. My last gas bill was over $300! Is it feasible to try to use solar power to heat the water instead or would that only work with the summer sun (when I wouldn’t need the heat anyway)? What about for my $40 electric bill? Someone please show me some numbers…
There are two issues here: solar(-assisted) hot water heating, and solar-generated electricity. The former should be easily findable in your local yellow pages, and the payback time is quite good. The latter is a more specialist thing and is not really financially viable, but if you wanted to do it for other reasons, yes, it is quite doable also.
Some local links for you;
http://pittsburgh.homeconnections.com/catlocal.Water-Heaters.Pittsburgh.Pennsylvania.-10420.html
Really what I’d like to know is if I can hook it up to my heating system so that it cooperates with the gas company, boiler, and thermostat, and how expensive that would be.
I live in Los Angeles, so YMMV, but…
1 - I recently got rid of my water heater tank and replaced it with a tankless water heater. Still uses gas, but my gas bill plummeted. THe thing is great. But they’re not cheap. And you need someone who can install it correctly – requires larger gas pipes than what you probably have in your house. Basically it uses a lot more gas when it’s on, but no gas at all when you don’t use hot water. So the tradeoff is an expensive one time replacement cost, followed by years of drastically reduced gas bills in regards to hot water.
Won’t affect heating in your home at all.
2 - Solar panels… I looked into installing those as well. Even with massive gov’t subsidies, tax incentives, etc, it would still run approx $20,000 to install them in my 1,800 sq foot house. They’re not cheap.
Long term they’d pay for themselves, but it’s a big up front investment to really get solar power set up. And yes, you can sell excess energy back to the utility, but I was told that really only adds up and makes a difference for larger institutions with large solar arrays, not single family homes.
Just a data point: My sister spent $12,000 or so on a grid tie solar system (no storage) which produces about 350 kWh per month averaged over a year. Power here costs about 7 cents per kWh and the power company pays her about 13 cents as an incentive.
It’s about 45 bucks a month credit to her. It will take a looong time to pay for the system, but she can afford it and feels good about it, which is cool.
FWIW, a quick google shows Pitt getting about 150 sunny days a year compared to Albuquerque with 280. (This just for a comparison)
Depending on power costs where you live, the above might help you come up with some rough numbers.
First, filmyak and Klaatu are talking about solar electric and that 's not the question here.
Here’s a link to the Department of Energy’s information on solar water heating. It goes into considerable detail on the types of systems available, approximate costs of installation, methodology for computing payback, etc.
You will also need to contact professionals in your area that are familiar with local codes and ordinances. For example, in my area, you are required to have a heat exchanger with a double wall construction such that the fluid that circulates in the solar collector never comes in direct contact with piping containing potable water. There should be resources in your area that are familiar with these types of regulations and can help you get a concrete idea of what a system will cost.
For a WAG, I’d guess around $2500 to set up a system with a payback of <3 years, but that’s a rough guess with absolutely no defensible basis in reality. 
Well, he did say “What about my $40 electric bill?” 
But that was an excellent post Rhubarb, and more on topic than mine.