The disclosure and our analysis
Evidence dates
Evidence: Loudoun County news release posted October 23, 2026; Code of Virginia § 15.2-2209.5, added by 2026 Acts chapters 567 and 568; the county's HEUF checklist and disclosure affidavit, linked from its legislative land use page. All read October 25, 2026.
What the county now requires
The county says it is acting to comply with legislation the General Assembly passed in its 2026 regular session. In Loudoun, it says, data centers are the most common example of a High Energy Use Facility, or HEUF. [Source 1]
1. **Power affidavit:** applicants file an affidavit and copies of correspondence with the electric utility showing the amount of energy and voltage the facility will require at full build out. The county uses this as the baseline for whether a project is a HEUF. [Source 1] [Source 4]
2. **Utility form:** the utility serving the HEUF must describe any new or existing substations that will serve it and the anticipated transmission voltage. [Source 1] [Source 2]
3. **Sound profile:** a site assessment must cover the facility's sound profile on homes and schools within 500 feet of the property boundary, and HEUFs must document their proximity to residential and school sites. [Source 1]
4. **Environmental effects:** Loudoun will also require the assessment to cover effects on ground and surface water, agricultural resources, parks, registered historic sites and forestland on or next to the site. State law lets localities ask for these; the county says it will. [Source 1] [Source 2]
The affidavit asks the applicant to check whether the facility will need less than 100 megawatts or 100 megawatts or more, to list all correspondence with the utility before filing, and to keep supplying future correspondence and updates before each hearing. The county says the form must not be altered. [Source 4]
Scope
The county says the requirements apply to all current and future legislative land use applications. They do not apply to sites seeking by right administrative approval. The county notes that since March 2025 every new data center application in Loudoun has needed a special exception from the Board of Supervisors, so in practice new data center cases fall under the rule. [Source 1]
The state law exempts an expansion or modification at a site with an existing approval if it adds no more than 100 megawatts. It also says the site assessment does not change the State Corporation Commission's authority. [Source 2]
The 100 MW threshold is the law's own measure: electrical power the applicant reasonably expects to need from the retail utility at the time of filing. It is a utility service figure, not critical IT load.
Status
This is a requirement in effect for applications, as the county describes it on October 23, 2026. It is not a pause or a moratorium on data center applications, and the county release does not mention one.
Buyer analysis
This is our analysis, not the county's. Power has been the binding constraint in Ashburn and the rest of Loudoun, and until now a buyer often learned how much power a planned campus had asked for, and from which substation, only through press reports or utility filings. If the affidavits and utility forms are made public with case files, which the release does not say, buyers and their advisors would gain a document trail for new Loudoun supply.
For operators, the rule adds paperwork that has to be ready before hearings and kept current as the utility conversation changes. It does not by itself change approval odds, but it makes power claims in a land use case checkable.
