Virginia’s massive and growing fleet of data centers already depends on dirty gas-fired power plants. But the pollution doesn’t stop there. Data centers also rely on large, on-site diesel generators—shipping-container-sized engines installed by the thousands.

As of fall 2025, 9,639 diesel generators have been approved for Virginia data centers, and nearly all are cheap, highly polluting Tier 2 models. When these generators run, they emit greenhouse gases, fine particulate matter, volatile organic compounds, and other toxic air pollutants that are proven to harm human health and the environment.

Diesel generators also leak carcinogens like benzene and arsenic, contributing to chronic respiratory diseases such as asthma and life-threatening illnesses including cancer—often in communities already burdened by pollution.

IN THEORY, diesel generators are to be used ONLY for emergency use. But in actuality, the Virginia Department of Environmental Quality (DEQ) has approved nearly 2000 for NON-EMERGENCY use - nearly 20% of all approved generators. These so called “back up” diesel generators are being used to power data centers outright, not just in emergencies - and they’re often clustered next to homes, schools and communities.

HB507(McAuliff) puts a stop to this by specifying that diesel generators may only be used for emergency purposes and that beginning in July 2027, a data center must use clean energy storage as its primary backup power source for a minimum of 2 hours in an emergency before it can revert to diesel. The bill also includes public notification provisions and directs DEQ and the Department of Health to assess the cumulative impacts of these generators.

Ask the Delegates on the House Agriculture, Chesapeake and Natural Resources Committee to vote YES HB507