September 14, 2026

Deconstructing Data Centers: What Is A Data Center and Why Should I Care?

Deconstructing Data Centers will break down the often complex legal, energy, regulatory, and political issues associated with data centers.

By Tom McFeeley, Media Relations Specialist

Data center construction continues to surge across the Midwest and the country. ELPC advocates for common-sense guardrails that protect ratepayers and the environment amid that growth. This series, Deconstructing Data Centers, will break down the often complex legal, energy, regulatory, and political issues associated with data centers.

Data Centers seem to be everywhere these days. If you haven’t heard about one popping up in your community, your uncle or mother-in-law has probably told you about one in theirs. Data center proposals are increasingly at the center of fierce political debates on the local, state, and national level, with many across the country calling for moratoriums on building new data centers.

In this Deconstructing Data Centers series, we aim to dive into the thorny questions around the environmental impact of data center development, including their energy and water use. But before we get to the hard stuff, we begin with the most basic question.  What is a data center?

What is a Data Center?

At the most basic level, a data center is a building full of computer servers – the machines that store and process digital information. But not all data centers are created equal. Historically, data centers were comparatively small and easy to miss. If you live in a city, you might walk by one of these older data centers on your way to work without noticing it.

Modern “hyperscale” data centers are an entirely different breed. These facilities can cover the footprint of dozens of football fields and draw as much electricity as a city all on their own. That size difference matters, because a single new hyperscale project can reshape a local utility’s plans almost overnight, long before most residents nearby even know it’s been proposed.

Equally important is the power generation that most modern data centers have onsite. Hyperscale data centers typically rely on hundreds of diesel or gas generators to ensure that the facility has power 24/7. In that way, these hyperscale data centers are really a 2-in-1: a power plant and a data center combined.

Why is this suddenly everywhere?

Data centers aren’t new. What’s new is the speed at which they’re multiplying and the sheer size of many new proposed data centers, and reason is artificial intelligence. Training and running an AI model, the kind behind chatbots, image generators, and search tools, takes dramatically more computing power than the internet browsing and video streaming that built the “cloud computing” boom a decade ago. Every time a company adds a new AI feature it needs more servers to run it and more electricity to power those servers.

Nationally, electricity demand from data centers is projected to roughly double in just two years.. Here in Illinois, ComEd currently has more than 90 proposed data center projects in its pipeline, adding up to over 29.5 gigawatts of potential demand, though it is highly unlikely anything close to that number will be installed in the near-term.

For context, 1GW of power is roughly equivalent to that of a big city. Some hyperscale data centers require 2 or 3 GW to operate, which is an extraordinary amount of demand in a single location.

Why should you care?

First and foremost, if you live near a proposed or operating data center, you’re probably worried about noise, air pollution, and water quality. These are real concerns: as discussed above, modern data centers often rely on onsite diesel or gas generators that spew pollution and make a lot of noise when they operate.

Even if you never live near a data center, the rapid growth in data centers may be touching your electricity bill. When more electricity users compete for a limited supply, the price of that electricity climbs for everyone. Utilities buy the right to have power available on high-demand days through something called a capacity auction, and those prices have already spiked. In one recent auction cycle, capacity prices in Illinois rose nearly ninefold. PJM, the organization that manages the power grid across a huge swath of the country including Illinois, cleared its most recent capacity auction at a record $16.4 billion. Ratepayers across the region will pay those costs, which means they eventually show up on your bill.

Greater electricity demand makes capacity scarcer, scarcer capacity gets more expensive, and utilities look to recover those costs from the customers already on the grid. Also, data centers’ huge demand for electrical equipment, memory chips, and other components is driving up costs for other products, such as cell phones. Meanwhile, utilities will start building massive amounts of new energy generation, including potentially large gas plants, to serve these data centers, and those plants use water and contribute to air and climate pollution on top of the water the data centers themselves need for cooling.

In addition to using water and contributing to air pollution, new power plants will cost the utilities money. It doesn’t matter whether a data center gets built in your town or three counties over. If it’s plugged into the same regional grid that serves you, its electricity demand can show up as a line item on your bill.

What will this series explore?

Understanding what a data center is, and why it’s growing so fast, is just the starting point. On an ongoing basis, we’ll dig into the questions that matter most as this buildout reaches communities across the Midwest, including:

• Could data centers bring their own clean sources of power instead of straining the grid?
• What do data centers mean for air quality and water in nearby communities?
• What happens when a data center skips the grid entirely and builds its own power plant next door?
• Why flexibility in data center workloads is important.

Each of these questions gets its own deep dive as this series continues, because Deconstructing Data Centers won’t aim to tell you data centers are good or bad. It will give you the tools to actually understand what’s happening, and why, so you can form your own opinion.