Most solar systems are connected to the electric grid. This allows you to provide power to the grid when your home’s production is greater than your usage and use power from the grid when it isn’t. Net metering is a policy that accounts for this flow of electricity between your home and the electric grid.
Net metering allows you to offset your energy consumption with your energy production. When your solar panel is producing electricity your electric meter runs backwards. When you’re using more power than your system generates, your electric meter runs forward. At the end of the month, your final electric bill is your total usage minus the electricity that your solar panels produced.
If at the end of the month you have generated more electricity with your solar panels than you have used, you can roll over this credit on your bill to the next month, just like ‘rollover minutes’ for your cell phone. With net metering, you get full credit for periods of excess solar production and are only billed for the total electricity you purchase from your utility over the course of the year. In April, if you have any leftover credits your utility company will send you a check for the remainder you’ve accumulated over the last twelve months.
In Maryland, solar customers are only eligible to receive credit for up to 200% of their home’s estimated annual usage. Your installer will work with you to size a system for your home that meets this requirement.