Solar: Basic Facts
Solar panels create electricity when the sun hits photo-voltaic cells, exciting electrons to flow and create DC current. There's a lot that has to happen before you're generating your own electricity. Let's cover the basic information you should know about solar energy.
First, the panels. They aren't particularly heavy and the average rooftop can easily support them. The panels create electricity without any moving parts in the form of direct current. In comparison to the entire electric demand of your home, each panel generates a small amount of electricity so you're going to need a lot of them if you want to match your electrical usage. And it goes without saying, I hope, but these only generate electricity when the sun is shining. Output actually ramps up to full strength when the sun is directly overhead (depending on the orientation of your solar installation) and then ramps back down as the sun descends. It's important to remember that the wattage rating will only be achieved at full direct sunlight and only lasts a few hours a day.
Now about that direct current: your solar panels make electrons flow in one direction. Our house current is AC or alternating current. DC electricity is not compatible with your household electrical system. This is where an invertor comes in: a key component to your solar system is the invertor that takes your DC current and makes it AC. There's a little loss from this conversion so keep that in your calculations.
Usually these panels are mounted on your roof. If you have a flat roof or a pitched roof that faces mostly south, you probably can have a solar system installed. If you face a different direction, have a sharply pitched roof or a lot of tree shade, you may not be able to have a solar system. No matter how enthusiastic you are about solar, these physical limitations are insurmountable.
Solar installations are not inexpensive. Be prepared to spend thousands if you intend to buy your solar installation outright. But this is not the only way you can end up with solar panels on your roof. There are many financial structures available that can make solar more affordable. Your options include leasing, financing or power purchase agreements with a solar provider. Some of these are made possible with the assistance of solar renewable energy credits or sRECS. These are credits that solar owners are granted based upon their installed capacity. Their value are market based and so they vary depending on the state in which you live. If you own your solar installation, you receive the sREC payments yourself. If you use one of the other structures, you may share this value with your financier or you may sign this over to the financier in exchange for reduced electric rates.
The other financial benefit is of course "free" electricity. Depending on how you finance your solar system, you will see some reduced cost of electricity. Your electric utility will credit you for the electricity you generate through solar. In some states, your utility may allow "net metering" which means that your electricity generation literally replaces what you would have purchased from the utility. In most cases, if you produce more electricity than you use, the carryover extends to the next month with the only limitation being that you can only get credit for as much electricity as you use in any given year. So if your solar system is big enough, you could in theory, pay nothing for electricity (other than the cost of your solar panels). Unfortunately, some states do not allow net metering so you may not see the benefit of your excess generation. In that case, it makes sense to only size your solar installation to what you can use in real time.
There are many nuances and details to solar generation, but hopefully this article has given you an overview of what is entailed if you're considering solar electricity for your home. We invite you to take advantage of the tools here on energyshopper.com to help you plan your solar installation.