Urban
PV systems of up to 12 KW are classified as residential, and are designed to run lights and appliances in the home. About 95% of these are rooftop solar arrays in the urban areas. Out in the suburbs or rural areas, a solar array may be installed on the main structure and/or outbuildings, on vacant ground, grasslands or hay fields or on a combination of sites.
The most common in the Puget Sound area is a directly grid-connected system. It provides power to the utility grid to be reallocated to points of need. The utility monitors the power produced by the system and buys the power from the producer at excellent rates on an annual basis.
The second type of system stores the excess energy in batteries that can be used for specific critical loads in case of a blackout. This system tops off the batteries when there is sunlight and then directs excess power to the utility grid.
In both systems, in the daytime, when excess power is being produced, the electric meter of the customer/producer actually runs in reverse, thereby lowering the cost of the power used throughout the year.
These systems may qualify for state sales tax relief, US tax credits and other subsidies.
Rural
As the name indicates, these solar systems are designed to address agricultural needs such as running farm machinery, charging tractors, supporting manufacturing/food processing equipment, etc.
There are two types of systems, both “grid-interactive”: the most common is a directly grid-connected system. It provides power to the utility grid to be reallocated to points of need. The utility monitors the power produced by the system and buys the power from the producer on an annual basis.
The second type of system stores the excess energy in batteries that can be used for specific critical loads in case of a blackout, This system tops off the batteries when there is sunlight and then directs excess power to the utility grid.
Rural PV systems like these may qualify for subsidies from the US Department of Agriculture, state sales tax relief and other subsidies.