What Is a Data Center? A plain-English guide for Ohio residents

The basic explanation

A data center is a building — usually a low, windowless warehouse on a 100–1,000-acre site — that contains thousands of servers, the computers that run the internet. Every time you stream a video, send an email, ask an AI a question, or buy something online, your request travels to a data center, gets processed, and the answer travels back to your screen.

For most of the past 30 years, data centers were boring buildings nobody noticed. They were sized to support web services that took milliseconds of computing time. The numbers were manageable: a typical large data center used 5–20 megawatts of power, hundreds of thousands of gallons of water per day, and employed a few dozen people.

That changed in 2023 with artificial intelligence. Training a single large language model takes thousands of high-performance GPUs running for weeks. Running AI services for hundreds of millions of users requires those GPUs running continuously. The new generation of data centers — called hyperscale — uses 100 to 500 megawatts each, with some sites reaching 1–10 gigawatts. The Ohio site at Piketon (PORTS Technology Campus) is permitted for 10 gigawatts at full buildout — more than half the total operating capacity of all online data centers in the United States today.

The three types of data center

Not all data centers are the same. Ohio has all three types in operation or proposed:

• Hyperscale — the largest type. Built for a single tenant (Amazon AWS, Google, Meta, Microsoft Azure, or Apple). Power: 50–500+ MW. Footprint: 100–1,000 acres. Examples in Ohio: Microsoft New Albany, Amazon Cosgray Road, Meta New Albany, Google New Albany, PORTS Technology Campus.
• Colocation — multi-tenant data centers where many different companies rent space. Power: 5–50 MW. Examples in Ohio: Cologix Johnstown ($7B), QTS New Albany, EdgeConneX, Vantage.
• Edge — smaller facilities (under 5 MW) located close to end users to reduce latency. Examples: cell-tower-co-located edge sites, regional university research data centers, Cincinnati hospitals’ tech rooms.

The Ohio constitutional amendment now in signature collection would prohibit data centers above 25 megawatts — effectively all hyperscale and most large colocation. Edge data centers and small colocation would be unaffected.

How much power does a data center use?

The honest answer is: orders of magnitude more than people expect.

The average Ohio home uses approximately 846 kilowatt-hours per month. A single hyperscale data center using 600 megawatts of continuous power consumes roughly 432,000 megawatt-hours per month — the equivalent of about 510,000 average Ohio homes, or roughly the power needed for the entire city of Cleveland for a month. Some current data centers running AI need around 600 MW to function. To put that in perspective, the power needed for ONE data center could power the average Ohio home for nearly 60 years.

This is why the regional electricity grid (PJM Interconnection) has seen capacity prices rise 833% in the most recent auction. It’s also why your AEP Ohio bill went up about $7.90 in April 2026, with another $10.28/month increase projected by 2028 per the Ohio Environmental Council. Read the full breakdown.

How much water does a data center use?

Cooling thousands of GPUs running 24/7 takes water. The numbers vary by cooling design but for a typical 100-megawatt hyperscale data center using cooling towers:

• About 528,000 gallons per day on average.
• Up to 1.5 to 5 million gallons per day at the highest end.
• 110+ million gallons per year for a 10–20 MW medium data center.

For context, Marysville's two operating data centers together consume about 10% of the city’s entire daily water supply. Central Ohio’s regional water study has documented groundwater subsidence — the actual sinking of the ground — from cumulative withdrawal pressure. Read the full breakdown.

How many jobs does a data center create?

Far fewer than the press releases suggest. Most operating data centers employ 10 to 30 permanent operations workers — a mix of facilities engineers, security staff, and IT technicians. Construction phases temporarily employ hundreds to thousands of trade workers, but those jobs end when the building opens.

Real Ohio examples:

• Microsoft Licking County: $1B investment, minimum 20 new jobs.
• Ark Data Centers (Iowa firm) Northeast Ohio: $136M campus, $4.5M tax break, exactly 10 permanent jobs.
• QTS New Albany: 10 new jobs, 4-building campus, 100% 15-year property tax abatement.
• Magellan Enterprises (Google subsidiary, Columbus): $54M tax break, 20 jobs.
• SoftBank/SB Energy PORTS Technology Campus: 4,000 construction jobs (4-year peak); 300–400 operational jobs ultimately scaling to 2,000.

According to Policy Matters Ohio analysis, the cost of Ohio’s subsidies works out to about $1 million per data-center job created. Food & Water Watch’s analysis of Virginia data centers found similar results.

What does Ohio give them in tax breaks?

Ohio data centers received $2.5 billion in state and local tax incentives between 2017 and 2024, according to an industry-backed Ohio Chamber of Commerce study. The breaks come from three sources:

1. Sales tax exemption on data center equipment (5.75% rate). Created in 2013, expanded to multi-tenant in 2013. Eligible projects must invest $100M+ over 3 years and pay $1.5M+ in annual payroll. Approved by the Ohio Tax Credit Authority.
2. Job Creation Tax Credit — 75% reduction in commercial activity tax over 15 years for qualifying projects.
3. Local property tax abatements — typically 75% to 100%, lasting 15 to 30 years. Sidney's Project Galaxy received a 30-year, 100% real-property tax abatement worth $180–$350 million in foregone revenue. Microsoft chose to decline abatements in Heath/Hebron — the opposite model.

If all currently announced data center investments by Amazon, Google, Microsoft, Meta, and Cologix qualify for the sales tax exemption, the cumulative tax cost could approach $1.6 billion.

Why are data centers in Ohio specifically?

Three structural reasons:

• Cheap, abundant land — Ohio has flat, undeveloped, agriculturally-zoned land at low cost in central, southwest, and northeast clusters.
• Existing electricity infrastructure — AEP Ohio, FirstEnergy, AES Ohio, and Duke Energy Ohio together cover all of Ohio. The grid was originally built for heavy industrial manufacturing (steel, auto, rubber). That same capacity now attracts data centers.
• Latency to half the U.S. population — central Ohio sits in milliseconds (network latency) to roughly 50% of the U.S. population, plus to Northern Virginia (the world’s densest data-center cluster), Chicago, New York, and the South. Fast network connectivity matters for end-user services.
• Tax incentives — Ohio's package is among the most generous of any U.S. state. Combined with Gov. DeWine’s veto of the legislative attempt to end the sales tax exemption in 2026, the policy signal has been: Ohio is open for data-center business.

What are the actual concerns?

Concerned residents and groups across Ohio are organizing around six specific harms:

• Water: aquifer depletion, well contamination, municipal cost-shifting. Full report.
• Electricity bills: transmission rate hikes, PJM capacity, AEP tariff. Full report.
• Noise: 24/7 cooling-tower hum, monthly diesel generator testing. Full report.
• Property values: mixed evidence; depends on distance and cooling design. Full report.
• Health: diesel emissions, fuel cells, air quality, premature deaths. Full report.
• Local control: NDAs, emergency ordinances, abatements with no public hearing. The Brown County Mt. Orab case (every village official signed NDA) triggered Ohio HB 695.

What can residents do?

Several actions are available, in increasing order of leverage:

1. Find what's near you. Check your county using the homepage risk map.
2. Document baseline conditions. If a project is proposed near you, baseline noise, well-water testing, and property-value comparables become legally important later.
3. Attend public hearings. Ohio Sunshine Law (R.C. 149.43) makes most planning, council, and trustee meetings open to the public.
4. File public records requests. Ohio law allows residents to obtain development agreements, NDAs (in some cases), and utility-survey records.
5. Sign the constitutional amendment — the most aggressive available policy lever. How and where to sign.

• Signal Ohio — Ohio's data center boom and political resistance
• Policy Matters Ohio — Indefensible tax breaks for data centers will cost Ohio (February 2026)
• Governing.com — Ohio Throws Hundreds of Millions to Tech Giants' Data Centers
• Ohio Chamber of Commerce / SRC EvalMetrics — Ohio data center economic impact study
• JobsOhio — Data Center Tax Exemption program detail
• Futurism — Ark Data Centers $136M / 10 jobs analysis (March 2026)
• DataCenterMap.com — Industry directory of operating Ohio facilities