Utility-scale systems may range from a capacity of 500 kW to hundreds of megawatts (MW).
For perspective, a 1-MW alternating current (AC) solar array can produce enough energy to power about 200 homes (depending on location) and may cover 5 to 7 acres. Because of the amount of land required, utility-scale projects are often located in more rural, less populated areas.
Because of their size, most utility-scale solar systems are installed in a fixed-tilt ground-mount configuration. This means that the panels are placed on the ground (rather than on a building), and are tilted in place to gain maximum exposure to sunlight.
A solar array can be installed on marginal land that can’t be used for agriculture or building sites, such as brownfield sites, landfills, and airport buffer areas. However, the site must be relatively flat or south-sloping without significant shading from vegetation or other obstructions.
Utility-scale solar systems owned and/or operated by an electric cooperative usually feed electricity directly into the transmission or distribution grid. The utility provides solar power to customers in one of two ways: by adding the power to the co-op’s power portfolio—which benefits all cooperative members; or by selling power directly to individual members who are motivated to purchase solar energy. Selling directly to consumers may be done in one of two methods, also. First, members may sign on to a cooperative-offered Green Power Purchase program that sells the renewable attributes of the power directly to members. Some cooperatives also support a community solar program, described below. Though utility-owned programs come in many variations, most programs feed power to the grid, rather than directly to a home or business site.
Economies of scale have a direct impact on costs. The 2015 calculations indicate that a large (20 MW-AC) solar system can be installed for an average of $1.55 per Wp-DC; the cost is even less in some areas.
