How do home solar panels work with net metering in Virginia?

Solar panels turn sunlight into direct current, an inverter converts it to the power your house runs on, and your home uses that first. When the panels make more than you are using, the surplus flows out to the grid through a two-way meter. Virginia's net metering rules credit that surplus against the power you draw at night or on cloudy days, and the credits carry forward within a 12-month net metering period.

From sunlight to your outlets

An individual PV cell typically produces about 1 or 2 watts, so cells are chained into modules, or panels, and panels into arrays.^[7] An inverter converts the direct current (DC) the panels make into the alternating current (AC) your house and the grid use.^[8]

The inverter layout matters later, when you look at production. With a string inverter, a set of panels shares one inverter, and shading or a problem on any one panel reduces what the whole string produces. Microinverters sit on each panel, so shade or damage on one does not affect the others, though they can cost more.^[8]

Solar power goes to whatever is running in the house first: the refrigerator, the air conditioner, the water heater. The energy your home uses straight from the panels never passes through the utility meter, which is why your bill does not show everything the system produced.^[5] Only the surplus reaches the meter.

What the meter measures

Virginia law defines net energy metering as measuring the difference, over the net metering period, between electricity supplied to you from the grid and electricity your system generates and feeds back.^[1] The meter must be able to measure power flowing in both directions.^[1][3] Dominion Energy installs a bi-directional meter once it grants contingent approval.^[5]

How the credits show up on your bill

The State Corporation Commission's net metering regulation sets the billing rules for investor-owned utilities such as Dominion Energy:

• Months with a surplus. In a month when you send more to the grid than you take, a customer on a standard (non-time-of-use) rate pays only the charges that do not depend on usage, plus any standby charge.^[3]
• Carrying credit forward. The credit is carried forward and applied to the next months in which you use more than you make.^[3]
• The year-end limit. The net metering period is the 12-month period following the date of your system's final interconnection, and each 12-month period after that.^[1] At the end of it, unused credits roll into the next 12-month period only up to the amount of electricity you were billed for during the period just ended.^[3]
• Getting paid for surplus. You are paid for surplus energy only if you sign a power purchase agreement with your supplier, requested in writing before the net metering period it covers begins.^[3] Under that agreement, an investor-owned utility pays the PJM day-ahead annual average market price for its zone, unless the two sides agree to more or the State Corporation Commission sets a different price.^[3]

On a time-of-use rate the math runs by tier. Dominion explains that credits can only be used in the same rate tier where they were earned, so on-peak credits offset only on-peak use.^[5]

The practical result: a system sized close to your yearly use gets the most from net metering, because surplus beyond what you use over a year earns either nothing or a wholesale market price, not a credit against the retail power you buy.

Size limits

Outside electric cooperative territory, a residential system can be no larger than 25 kilowatts.^[1] On top of that, a system installed after July 1, 2020, cannot exceed 100 percent of the home's expected annual use in a Phase I utility's territory or 150 percent in a Phase II utility's territory, based on the past 12 months of bills.^[1] Dominion's own page states the 150 percent limit for its customers.^[5]

In electric cooperative territory the residential limit is 20 kilowatts,^[2] and a co-op residential customer whose system exceeds 10 kilowatts pays a monthly standby charge.^[2] In Dominion's territory, the standby charge applies to residential systems larger than 20 kilowatts AC.^[1][5]

Getting connected to the grid

Under Virginia law, you must notify your utility and receive approval to interconnect before the system is installed.^[1] The utility has 30 days from notification to decide whether a residential system meets the interconnection requirements.^[1]

At the end of the job, the licensed electrician who installs the system signs the notification form certifying it was installed to the manufacturer's specifications and the National Electrical Code. When the customer or a licensed Virginia Class A or B general contractor installs the generator, a signed final electrical inspection can be used instead.^[4] Dominion then sends a Permission to Operate email to the customer and the installer.^[5] Your installer normally handles this paperwork, and the system should not be switched on for export until permission arrives.

On cost, the statute says you bear reasonable costs of any extra controls or tests the utility needs,^[1] and Dominion says there are often no charges to interconnect small residential systems.^[5]

When the grid goes down

If the grid goes out, a standard grid-tied system is forced offline so it cannot send power onto lines that utility crews are repairing.^[5] The U.S. Department of Energy explains that household inverters ride through small voltage or frequency disturbances but disconnect and shut down when a disruption lasts too long or is larger than normal.^[8] The only way to keep solar power running in an outage is an energy storage system and a transfer switch.^[5]

Net metering terms are under review

Section 56-594 requires the State Corporation Commission to hold a net metering proceeding and set a new rate structure for customers who interconnect after the date in its final order.^[1] Nothing in that final order affects customers who interconnect before its effective date.^[1] Virginia Energy says net metering is currently being reviewed at the SCC.^[6] Before you sign, ask your installer which tariff the savings estimate assumes and what changes if new terms apply on your connection date. Our answer on what to check before signing a solar contract covers the rest of that list.

Plug-in solar from 2027

From January 1, 2027, Virginia law allows plug-in solar devices of up to 1,200 watts that connect through an ordinary outlet.^[9] They are exempt from interconnection and net metering, but you must notify your utility on the SCC's form before installing one, and the device must stop feeding power during an outage.^[9] Because they sit outside net metering, they suit renters and small balconies rather than replacing a roof system.

When to call a licensed pro

A grid-tied system is electrical work tied into your service panel, and the interconnection rules expect a licensed electrician's certification or a passed inspection. The Board for Contractors' alternative energy system (AES) specialty covers installing solar generation from the customer's meter, but it does not include electrical work,^[10] so the company you hire needs an electrical licence too, or a licensed electrical subcontractor. Check the licence on DPOR's record before you sign.

For prices and what drives them, read how much solar panels cost in Virginia. Browse solar installers on Loclis, find electricians in Blacksburg, or read more electrical answers.

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