HOW NET METERING WORKS
You may have noticed the absence of a method to store the energy your solar energy system produces during the day. After all, what happens on a cloudy day? Or at night?
Batteries used to be a big part of early solar energy systems. Rather than running power directly into the home, the power inverter would send power to a bank of batteries that would store the power until it was needed.
These batteries were not only large but they were also incredibly expensive. Some battery systems could cost as much as twice the price of the rest of the system, including the panels!
A more efficient and cost-effective solution had to be developed. This is know as net metering which began first in the 1980s and has become the most utilized agreement between utility companies and homeowners to date .
With net metering, also known as an interconnection agreement, batteries are replaced by none other than the power grid itself. Excess power produced by the home solar energy system is fed back into the local power grid and the customer’s power meter literally spins backward as a result. During cloudy days and evenings, power comes to the customer’s home directly from the power company and the meter resumes spinning in its normal direction. Once the sun is back over your panels and generating power, excess energy is once again fed into the local grid and the meter spins backward, negating the costs incurred while the home was using grid-supplied power. So to put it in simple terms, net metering is the ability to build 1 to 1 “credits” with unused so they can be used at a later date when they are needed