DEQ Does Not Grant Approval for Data Centers to Run Diesel Generators Outside of Emergencies

Piedmont Environment Council still questions the DEQ's priorities


The Virginia Department of Environmental Quality announced today it would not be moving forward in considering a variance that would allow for data centers in Loudoun County to run on diesel generators outside of an emergency situation such as a blackout. The variance would have allowed data centers to act proactively from March through July when the electrical grid may be strained. 

The original variance included Loudoun, Fairfax and Prince William counties.  The DEQ exempted Prince William after dozens of residents attended a public hearing in opposition. 

The problem with diesel generators is two-fold: the noise and the air pollution. The generators are extremely loud. Additionally, their exhaust can cause short-term and long-term health effects, especially for vulnerable populations such as those with asthma, young children and the elderly.

The DEQ did not reject the variance. According to its press release, the data centers, utilities and the regional transmission organization are addressing the electrical grid concerns amongst themselves without the need for the variance at this time.  

"DEQ [Virginia Department of Environmental Quality] is canceling the public notice and not moving forward at this time with the consideration of an issuance of an order granting a temporary local variance for data centers located in Loudoun County."

"As stated in the initial public notice and draft order, the proposal was meant to address a concern for the area in which there may not be a sufficient amount of electricity for data centers due to severe, localized constraints in electricity transmissions through 2025."

"The proposal was intended to be an option to allow the data centers to continue to serve their customers, maintain the integrity of (the) internet, and alleviate demand on the electric grid during periods of extreme stress."

"Given further discussion with stakeholders and public comment on the proposal, DEQ believes that these issues are now being addressed between the data centers, the utilities, and the regional transmission organization (PJM interconnect)."

"If needed in the future, DEQ stands ready to assist in ensuring that Virginians have a reliable, affordable, clean, and growing supply of energy."

The Piedmont Environmental Council responded to the announcement. While the council celebrates the outcome, it nonetheless critiques the DEQ for not adhering to its mission. 

The council notes that the DEQ did not stop the variance out of concern for public health or the environment but because it was not feasible. It questions the DEQ's mission and asks why it is so concerned about the Commonwealth's energy supply, rather than its environment. 

"The Virginia Department of Environmental Equality’s withdrawal of its proposed variance that would have allowed data centers to circumvent Virginia’s air pollution control regulations limiting the use of heavily polluting, industrial-sized, emergency diesel generators is a step in the right direction, and although we’d like to think it’s an indication that DEQ recognizes its waiver would be harmful to human health and the environment, the DEQ notice, unfortunately, makes it clear that the agency has done the right thing for the wrong reason."

"The Data Center Coalition, made up of big data center companies like Amazon, Google and CyrusOne, asked that the variance be pulled because of technical, federal regulatory, and operational challenges to its implementation. One aspect they highlight is that Dominion does not have a demand response program, which usually incentivizes or compensates large users of electricity to shed electrical load during peak demand. DEQ responded by pulling the variance and assuring that it “stands ready to assist in ensuring that Virginians have a reliable, affordable, clean, and growing supply of energy."

"That’s a disappointing statement given that it is not even close to DEQ’s mission. Rather, DEQ was created 'to promote the health and well-being of the Commonwealth’s citizens, residents, and visitors.' And yet, DEQ’s variance withdrawal failed to acknowledge the significant public health impact of the more than 4,000 highly-polluting, industrial-sized diesel generators, over 11GW worth. Diesel exhaust has well-known human health impacts, especially on vulnerable populations like children and the elderly, leading to serious health conditions like asthma and respiratory illnesses and worsening existing heart and lung disease. In addition, these emissions further contribute to greenhouse gas emissions from the dramatic increase of fossil fuels resulting in regional ground-level ozone, acid rain, and global climate change."

"Although the people of Virginia won this battle, the issue of explosive energy demand from continued data center development is something Virginia needs to get a handle on. Data centers have been and continue to be approved at a rapid pace and built without the necessary energy infrastructure to support them. As a result, backup diesel generators could increasingly be put to use in Loudoun County and throughout northern Virginia as power becomes even more constrained, putting public health at risk."  

The Piedmont Environmental Council mission is to protect and restore the lands and waters of the Virginia Piedmont, while also building strong and resilient communities. Founded in 1972, PEC is a 501(c)(3) non-profit and accredited land trust. Learn more at


About DEQ

The Virginia Department of Environmental Quality protects and enhances the state’s environment and promotes the health and well-being of the citizens of the Commonwealth. We are committed to cleaner water, improved air quality and the productive re-use of contaminated land.

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