Investigate. The U.S. Department of Energy has detailed maps illustrating the power-generating potential of U.S. regions for the production of solar, wind, geothermal and hydroelectric power (separate for each type). Also research local sunrise and sunset information and weather patterns. Use this information to identify the best energy source at your location.
Photovoltaics are suitable for most any location in the U.S. But parts of Arizona, California, Nevada, New Mexico and Texas get the most direct sunlight---an average of 7 to 8 kWh/m2 per day. The best places to develop wind resources in the U.S. are along the East and West coasts and in the Midwest plains.