Selling power back. Every state and city is different in this regard, but most people can sell energy back as long as they produce in excess of their own needs. This is called net metering and it allows you to sell the extra energy back to the utility company. Most people will find that they can sell about 20 to 40 percent of the energy they produce. You will get paid per kilowatt based on the current rate. Some states have caps on how much can be sold per year. Contact your utility company to find out what forms you must fill out, whether you need special insurance to sell the solar energy and if there is a cap on how much you can sell.