Most utilities do have what is called "net metering" which means that a solar or wind system installed on your property can be used to generate electricity and turn the utility meter backward. This allows you to offset power that you would otherwise buy from the utility. As long as you only generate the amount of power you traditionally use on a monthly basis and don’t generate a lot extra to sell back you will fit into the net-metering category. These systems can be set-up to charge batteries for back-up power systems in addition to turning the utility meter backwards but it adds some complexity and increases cost. Be prepared to make contact with your utility to see what their rules are. If you are pursuing a wind electric system, be prepared to contact the county or township to make sure that there are no restrictions against tall towers. Some utilities or townships are very easy to deal with and the negotiations go off without a hitch. In some cases, they make it very difficult to even get the information about what you can do.
If you live in sunny Florida, Texas, southern California or the windy Midwest you may be able to install a renewable energy system for less than these average numbers indicate. Maybe you are just powering a cabin or an RV which use very little power generally. Better yet, maybe you are just building your home and you will have the opportunity to make it well insulated, efficient, oriented properly towards the south to take advantage of passive solar heating and daylighting. Doing all of these things will dramatically reduce the amount of energy you use thereby reduce the cost of a renewable energy system.
The big question you need to answer before investing is why are you interested in using solar or wind energy? Is it because you need some back-up electricity for when the utility grid is unavailable? Or is it because you want to spend less money per month on electricity? In either case it is possible to install a smaller and less expensive system that will supply a portion of your electricity needs.
If it is because you want to spend less money per month then you may want to start by hiring a solar person or energy efficiency person in you area to come into your home and suggest ways of reducing your electricity consumption. These ways may be as easy as changing all your light bulbs to compact fluorescent bulbs or as difficult as changing out your old electric water heater for a propane or natural gas model. Any of these things will save money to different degrees. Once your home is as efficient as it can be, then you may want to consider installing a wind generator for "utility intertie". This system may not cover your entire electricity bill and can be as large or small as your budget allows with certain limitations on the size of the utility intertie inverters you have to choose from. This type of system is subject to acceptance from your local utility so you may want to contact them to see what their terms are. This type of system has very limited battery storage capacity in order to keep the price down so it is not typically thought of as offering back-up power.