Power lines and the grid

Background in two minutes

Most new power demand in Northern Virginia comes from data centers, and moving that much electricity takes high-voltage transmission lines and substations. Utilities such as Dominion Energy and private developers propose the projects.

The county's power over them is split. Transmission lines are approved by Virginia's State Corporation Commission (SCC), not the county, so the Board can only take positions and testify. Substations on private land, however, need a county special exception, which means the Board can approve or deny them.

The case for building new lines

Utilities and grid planners say demand is growing fast and the grid needs new capacity to stay reliable for homes, hospitals and businesses as well as data centers.

The county itself has supported some projects when they use corridors that already exist. In 2025 the Board backed Dominion's Morrisville to Wishing Star line on the condition that it stay in an existing right-of-way rather than cut through neighborhoods.

The case against new routes

Opponents argue that new routes through western Loudoun would damage rural landscapes, farms and historic areas, and the Board has formally opposed both the NextEra 500-kV route and the Valley Link 765-kV line on those grounds.

Others question whether every project is really about reliability. When the Board denied the Tech Park at Dulles substation in 2026, the county said it was not a grid reliability project and would mainly attract new high-wattage users that would require even more lines.

What the county actually did

Because the SCC has the final say on lines, most of the Board's actions are positions and filings. Its direct power shows up in substation decisions.

• Apr 2, 2024County joins state case on Aspen-Golden transmission line Joined SCC case
  Files to participate in Dominion's State Corporation Commission application for a 500-230 kV line and substation along Route 7.
• Apr 16, 2024County opposes NextEra 500-kV route through western Loudoun Resolution adopted
  Opposes the proposed transmission route and encourages using existing transmission rights-of-way instead.
• Jul 1, 2025County backs Morrisville–Wishing Star line in existing right-of-way Position adopted Vote: 8–0–1
  Supports Dominion Energy building the transmission line within its existing right-of-way rather than an alternative route through neighborhoods.
• Sep 15, 2026Board opposes Valley Link 765-kV line through western Loudoun Resolution adopted
  The county has no formal regulatory role over the line but may testify when the developer files with the State Corporation Commission, expected in 2027.
• Sep 15, 2026Tech Park at Dulles substation denied Denied
  The county said the substation was not a grid reliability project and could draw new high-wattage users needing new high-voltage lines.
• Sep 15, 2026Proposed pause on data center and substation application votes Vote Oct 20
  A resolution would pause final votes on legislative data center and substation applications for up to 12 months, retroactive to Sept. 15. Scheduled for consideration Oct. 20, 2026.

Open questions

• What route will Valley Link propose when it files with the SCC, expected in 2027, and will the county testify?
• Will the proposed pause on substation applications pass on Oct. 20, 2026?
• What substation standards will Phase 2 of the data center rules include?