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Not sure what 1BOG is exactly, but generating energy from sunlight is not that complex and can range from simple solutions to comprehensive, like everything else. It's also a lot of fun to learn about. I recommend taking a home study course or two. Do some research and find out who the reputable installers are in your area and have a couple of them come out and look at your site and make some recommendations.
Some basics: As Scott mentioned, there is solar PV (electric) and solar thermal (hot water). Solar electric generates electricity from photovoltaic panels and is usually somewhat expensive to install up front, but can payback well over time. Solar thermal heats water by passing it through glass tubes or flat panels and storing it in a tank or pre-heating your own water heater. Solar thermal captures far more BTU's for a given amount of dollar investment so I often recommend people go that way first if they just want to make a dent in their overall energy bill, especially if they use a lot of hot water, especially for radiant heat.
Solar PV is used for generating electricity and is more expensive, so there are several things to keep in mind:
1) It will always be cheaper to SAVE a watt than GENERATE a watt. So first make sure you don't have a lot of energy hogs in your household. Are all your lights CFL or LED? Do you have energy star appliances? Do you have an old refrigerator or icebox in the garage (bad). Are things on timers? Are your dryer and primary heat source gas? Please do not try to use PV to electrically heat your home - it would be far better to use solar thermal to supply radiant heating.
2) Once you have cleaned up the energy efficiency of the home then it is time to look at your monthly energy usage in KWh. This will help you figure out the size of the system you will need. For example, 300KWh/month is 10KWh per day. Thereoretically, if you have a good 5 hour solar window per day then a 2KWh system (x 5 hrs/day) could potentially supply most of your electricity, but there are losses to consider, primarily shading and the low light in the winter months. A critical part of this is determining when your load is highest - winter or summer? In California summer loads are often highest due to AC in the afternoon which is also an optimal time to generate electricity from the sun and pipe it back into the grid.
3) Do you have a roof that faces south or close to south and is it free of shading, especially in the winter months when the sun is low in the sky? Many people do not have a good orientation or adequate solar window (hours of direct sun). Solar PV is very sensitive to shading, ie. the current will drop way off if only part of the array is shaded. What latitude are you at? Big difference between Seattle and Phoenix. There are solar irradiation charts for the US online.
4) Lastly - the financials. How is your current energy charged - is it a tiered rate, where you are charged higher rates as you use more? This is very favorable to a solar PV system because you can size it conservatively and whack off the most expensive kilowatts from your bill. Will your electric provider "buyback" electricity that your system puts into the grid? At what rate and time of day? Typically they pay more during periods of peak use - cold winter mornings, hot summer afternoons, etc.
A big piece of the financial consideration of course are the state and federal tax incentives. Once you have figured out all of the other important considerations and have a rough idea what size system would do the job for your specific circumstances, then you can look at what it will cost outright (get several bids) and how the incentives affect you personally (tax bracket, etc). In some states they can take up to half of the cost off the system. And don't forget resale - it will add to the value of your home.
, Sat, 5 Mar 2011 01:02:15
, Thu, 3 Mar 2011 06:38:02
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