Data centers have been a hot topic around Cleveland and the rest of Ohio as the boom continues to touch communities across the state. In May a permit for a hyperscale data center was rejected in Cleveland’s Slavic Village, and a short-term moratorium is was approved by Cleveland City Council last week, bringing the data center boom to the forefront of many Clevelanders’ minds.
Residents cite concerns for increasing electric prices, adding another heavy user to an already-stressed grid, noise pollution, and concerns about water usage, but what do we know about the environmental cost of hyperscale data centers?
How much energy do hyperscale data centers use?
Hyperscale data centers are the “if you give a mouse a cookie” of the energy grid. A single modern AI data center can gobble up the energy needed to power 100,000 homes, well over half of the occupied homes in Cleveland, according to the 2020 census. Some of the larger data centers under construction across the country could consume 20 times that amount, according to the International Energy Agency, an international organization working to shape a secure, affordable and sustainable energy future for all.
Data centers in the United States are largely run on fossil fuels. A 2025 International Energy Agency report found that 55 percent of the energy powering data centers in the U.S. comes from natural gas and coal, with natural gas accounting for 40 percent and coal accounting for 15 percent.
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‘Far-reaching’ consequences for air quality from powering data centers
There has been a lot of focus on the short-term impacts of hyperscale data centers, such as increased energy costs and increased instability of the grid, but the long-term climate impacts loom larger in the background.
“When you put a data center on the grid and it starts consuming electricity, that electricity often comes from a power plant somewhere, whether it is a natural gas plant or coal plant. The more that power plant runs, the more emissions it produces, and those emissions are partly greenhouse gases, which contribute to climate change and also local air pollutants,” said Michael Craig, an associate professor at the University of Michigan that works on environmental systems and environmental impact.
“There are far-reaching consequences,” Craig said. This means data centers can have air quality impacts far beyond where they are located, causing environmental health concerns for vulnerable communities near power plants.
Along with pollution from the power plant the data center causes from daily use, most data centers rely on several diesel back-up generators, and sometimes hundreds of generators, to ensure around-the-clock access to power. The American Cancer Society links cancer and heart and lung disease to the pollutants released when burning diesel fuel.
No laws, little regulation of data center water use
Midsized data centers can slurp up between 100,000 and 300,000 gallons of water a day, while hyperscale data centers like the proposed project in Slavic Village that was blocked can consume as much as 5 million gallons per day.
There are currently no laws requiring data centers to report their daily water usage, making it more difficult to accurately track how much any given data center is actually using.
The Great Lakes Compact, a legally binding agreement between the eight Great Lakes states and two Canadian provinces, requires large water users drawing from a private well to report whether they use more than 100,000 gallons a day. If a data center is hooked up to the municipal water supply, there is no law requiring they report their water usage.
Experts say more reporting and regulation could help
Right now Cleveland doesn’t have any hyperscale data centers, but there are several across the state. Cleveland does have plenty of smaller data centers of different sizes, sometimes called carrier hotels, that can host servers for businesses and the government. They can have similar water, energy and cooling needs as hyperscale data centers but on a much smaller scale. And their backup energy is often supplied by diesel “generator yards” that pollute.
Hyperscale data centers often use more energy because of the number of servers they power and cool, but in some ways they can be more energy-efficient than older, smaller data centers. Currently, there are few reporting requirements to measure things like water and energy usage, making it difficult to know the true environmental cost of Cleveland’s smaller data centers.
“There needs to be more safeguards,” Craig said. Regulations can come from state and local governments, agreements like the Great Lakes Compact, or from regional transmission organizations such as PJM Interconnection, the power grid operator that serves Ohio.
“Communities might not really have a voice with PJM, but the State of Ohio has a very strong voice,” Craig said. State and local representatives are a great place to start to bring the community voice to the table, he said.
