A solar electric system generates the most power when the sun is strongest, during midday and afternoon hours. That is also the time when demand for electricity is highest.
To meet this afternoon peak demand, utilities fire up smaller “dispatchable” power plants that are often more expensive to run and more polluting than the larger, base load generating plants.
Powering a home or business with solar energy can reduce the utility’s peak load and reduce the peak generation by the utility. This results in lower overall energy costs and cleaner air. Having many small grid-connected solar arrays also increases the capacity and stability of the grid.
For every 1 kW of solar power installed, utility power plant emissions are reduced approximately 1500 pounds per year. Over a thirty-year life, each 1kW of solar power prevents 21 tons of CO2 emissions from being released by conventional energy sources.