When you install solar on your home, your net meter is what allows your utility provider to keep track of the energy flowing to and from the electric grid. Net metering is what allows you to be billed for the excess energy from your solar system that you supply to the grid as well as the energy that you consume beyond what your solar installation is producing.
At some points during the day, say a nice sunny spring afternoon in central Oregon when you’re out cross country skiing and your house is empty, your solar installation will produce more energy than your home is using at that time. In Oregon you are allowed to put that energy onto the electricity grid and get a 1-to-1 credit for the energy that you have produced. You can then also still pull energy from the grid, just like you do in a home without solar, in the evening when the sun has stopped shinning or when your electricity demands surpass what your system is producing.
Your net meter keeps track of all of the excess energy you produce as well as all of the energy you consume. At the end of the month you are billed for the net amount the energy that you used.
If you are a Pacific Power customer and you produce more energy in a month than you can use, those credits will roll over so that you can use them in future months. Many homes roll over electricity during most of the summer months and use those credits in the fall when it isn’t as sunny out. Your excess credits reset on an annual basis on April 1st. You will be unable to use these excess credits and they will be transferred to Pacific Power’s low income assistance fund. Your solar contractor will help you determine how much energy you currently use and help you size a system that meets your current and future electricity needs.
If you are a Central Electric Coop customer, and you produce more energy in a month than you use, you will be credited on your utility bill at the wholesale rate of power which is what CEC would pay to purchase the electricity on the open market. This means that you will be credited at a rate lower than you currently pay your utility for power. Your net meter will reset each month.
With a net metered system you are still connected to the utility grid and you have no need to have batteries to store energy. Some homes choose to have a battery backed-up system so that they still have the ability to use power from their solar installation even when the power goes out. With your typical net metered solar installation, when the power goes out, your whole system shuts down. This is so that your system can’t produce excess energy and feed it onto the utility grid when the utility is out working on the lines.