How Net Metering Works
The energy you generate from your solar photovoltaic (PV) system is used to power your home throughout the day. On sunny days, your system may produce more electricity than you need. When this happens, this excess energy is exported to the Eversource electric grid. Net metering is one way you can be compensated for this extra energy your system produces.
At the end of each billing month, the total electricity you sent back (sold) to the grid will be subtracted from the total amount of energy you used (purchased) from the grid. This determines your net amount.
The formula is simple: energy you produce - energy you consume = net energy.
State laws cap the number and size of projects that can benefit from net metering. Residential solar installations smaller than 10kW will usually qualify for net metering. Systems larger than 10kW may receive credits at a reduced rate. Talk to your solar installer or review the Massachusetts net metering guide and the Eversource solar contractor's net metering guide to see if your system is eligible for net metering.
Expect New Meters
During the installation of your solar system, Eversource will replace your existing electric meter with a new model that reads the amount of electricity flowing in and out of your home. This meter helps us calculate your monthly net metering credit. And, if you participate in the SMART program, your solar installation will include a second meter to measure your production to earn SMART incentives.
Net Metering Credits
When your solar system produces more energy than you use, you earn net metering credits. These credits can be used to reduce your monthly electric bill or be distributed to other Eversource customers, a practice known as virtual net metering.
If your system is 10kW or less, the rate at which you earn net metering credits will be lower than the full retail rate you pay for power from Eversource. This is because charges for energy efficiency, renewable energy and distributed solar are excluded from the net metering rate.
The net metering rate (as determined by state law) will change as our rates fluctuate. Systems larger than 10kW may receive a lower net metering rate.
Your Monthly Electric Bill
With net metering, your monthly bill will look different than it did before you installed a solar energy system. In months where you produced more energy than you used, your Eversource bill should show a negative balance because net metering credits were applied to that bill and possibly roll over to future bills.
If you use more electricity than you generate, Eversource supplies the power you need at the standard rate. If this occurs over the course of a month, net metering credits will not appear on your bill.
View sample net metering bill for more details.
Apply for Net Metering
If you are a customer applying to interconnect a new solar system, your installer will apply for net metering for you. To receive net metering service for your new system, you will need to complete a Schedule Z form. Your installer can help you with the application process.
Virtual Net Metering
If you earn net metering credits by producing more energy than you consume, you can share your credits with other Eversource customers in Massachusetts.
You are limited by your system location to where you can transfer credits. In western Massachusetts, you can share net metering credits only with other customers in western Massachusetts. In eastern Massachusetts, other customers must be in your same load zone of either southeastern (SEMA) or northeastern Massachusetts (NEMA) to receive credits. View the ISO load zone map for more information.
You can change your net metering credit allocations up to two times per calendar year by submitting a new Schedule Z form to Eversource.
When It's Time to Move
If you move and have net metering credits on your bill, you can submit a final Schedule Z form to allocate the credit balance to other Eversource accounts, including the new account you're moving to. If you choose not to do this, your credits will be used to offset net metering recovery surcharges for all customers.
Net Metering and SMART
Net metering is a separate program from the Massachusetts SMART incentive program but both provide financial benefits to solar homeowners. You can take advantage of both programs.