WHAT IS NET METERING?
An example about how net metering works
Imagine the simplest possible metering arrangement: a single, 1960s-standard electromechanical meter. Now imagine that a residential customer, Ray McSolar, added rooftop photovoltaic (PV) system (also known as a solar-electric system) to his home, on his side of this meter. Ray wakes up early for his job; on most days, he is out of the house before sunrise. In these dark morning hours, Ray makes his coffee and breakfast while watching the morning news on TV. The electric meter spins forward as Ray is consuming electricity from the grid.
Determined not to waste a bit of electricity, Ray shuts off all of his appliances as he heads off to work. Ray’s solar panels now start churning out electricity as the sun rises—electricity Ray sends back to the overstressed grid. His meter now spins in reverse.
When Ray returns at night to cook dinner and relax in front of the TV, the meter spins forward again as he consumes more electricity than his system generates. The result? Ray’s bill will show only his net consumption of electricity from the grid. Whether it is a sunny month or a month in which Ray’s electricity use is low, any excess electricity his system generates is rolled over to his next bill, just as he might rollover excess cell phone minutes.
In effect, net metering is a simple billing arrangement for customer-sited DG. Without exception, significant deployment of clean, customer-sited DG occurs only in states with modern interconnection and net metering policies.