Data Centers Overload Virginia's Grid, and Ratepayers Will Pay for the Backup

On Thursday evening, September 18, 2026, residents across Northern Virginia saw flashes and heard booms near power lines, then watched their lights flicker.^[1] The cause: a Dominion Energy transmission line tripped, but the automated system held. What went unreported in the initial coverage is the scale of what almost broke. This incident follows a July 22 event in the same area when equipment failure on a Dominion transmission line serving data centers caused three data centers to switch instantaneously to backup power, removing roughly 3 gigawatts of demand from the grid. That swing rippled across the entire Eastern Interconnection, affecting an estimated 100 million homes and 238 million people.^[8] The grid did not fail that day, but it nearly did; full frequency recovery took roughly ten minutes.^[8]

This is not a weather story or a maintenance failure in the traditional sense. This is a load problem. Virginia's data center boom, concentrated in Loudoun County around Ashburn, is now large and volatile enough to destabilize the regional grid. A state legislative commission estimated that data center expansion is the leading driver of a potential doubling in state electricity demand over the next decade, with a typical Dominion residential customer facing rate increases of $14 to $37 annually as a result.^[3] The transmission and distribution infrastructure Dominion built for residential and small-business customers is now being asked to handle loads that swing by thousands of megawatts in seconds, with no contractual requirement that the data centers stay connected during a fault. When they disconnect, the grid feels a jolt; when they reconnect, another one. The utility responds by requesting transmission upgrades and substation expansions. Dominion has pursued power line expansions and new substations in Northern Virginia to meet data center demand.^[1] Those upgrades are capital; capital earns a regulated return. Who funds the return? Ratepayers, most of whom do not operate data centers.

The mechanism is straightforward and legal. Under traditional cost-of-service regulation, utilities recover all prudently incurred capital costs plus a return on equity (typically 9 to 10 percent annually in regulated states). Data center operators negotiate long-term power purchase agreements that lock in prices and demand certainty; Dominion builds the wires to serve them; Dominion's shareholders earn the return on those wires; and residential and small-business customers pay the baseline rates that fund the utility's cost of capital. The data center does not bear the risk of a fault that knocks 3 gigawatts offline; the grid does. The operator does not pay for the redundancy or the faster restoration mechanisms the grid now needs; the utility does, and the utility passes the cost forward to ratepayers. A former national security expert warned that the combination of grid strain and data center concentration in Northern Virginia poses a cascading risk to critical infrastructure; foreign adversaries could attack the grid and cripple U.S. infrastructure.^[2] Whether or not that threat is imminent, the economic transfer is immediate: Dominion builds for data center load; customers pay for the poles, wire, and fiber; shareholders pocket the return.

The question regulators should ask is whether Dominion's existing reliability obligation, to maintain SAIDI and SAIFI within agreed limits, is being met. If data center loads are now so large that a routine transmission fault can knock them offline and send disturbances across a continent, then the grid is not reliable for the load it has been asked to carry. Dominion should either (1) require data centers to maintain synchronous generation or fast-response storage on-site to ride through faults without disconnecting, or (2) size and reinforce the transmission and distribution network to handle them without loss of service, and pay for that work itself by earning a lower regulated return or by negotiating cost-sharing with the data center operators. Neither is happening. Instead, Dominion collects baseline rates from all customers and then requests hardening riders, surcharges ostensibly for storm resilience, but in this case, for data center volatility, which ratepayers fund without choosing the load that created the problem.

Virginia's Joint Legislative Audit and Review Commission identified the data center expansion as the leading driver of future electricity demand and recommended a moratorium on new approvals until the state has a clearer understanding of the power and water they require.^[3] That recommendation has not been adopted. Instead, Dominion continues to expand in Loudoun County, and regulators allow the utility to bundle infrastructure costs into rate cases without segregating the capital that serves one customer class from the capital that serves another. A performance-based regulation framework with symmetric reliability penalties and incentives, similar to Britain's RIIO model, would tie Dominion's earnings to the grid's ability to maintain frequency and voltage stability under all connected loads. If a data center fault causes instability that propagates across the region, Dominion loses revenue. That creates pressure to either demand that the data center self-insure against disconnection or to refuse service at the price offered. Today, there is no such pressure, because the return is guaranteed regardless of what the grid actually delivers.

A third path is available: municipal or cooperative ownership of the transmission and distribution assets serving data centers in Loudoun County, with governance that requires data centers to fund their own resiliency and redundancy, and that keeps rates for residential and small-business customers insulated from the volatility of a single customer class. That option requires state action to authorize municipal acquisition or a cooperative buyout, and Dominion's political power in Richmond makes it unlikely. For now, ratepayers should know what the flashes and booms on September 18 meant: the grid that serves you is now engineered around a load you did not consent to, owned by companies that did not ask your permission, and paid for by you.