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What just happened to my electric bill?

The root cause and what you can do about it

Published Nov. 3rd, 2025

If you're reading this, there's a good chance you saw your ComEd bill shoot up in the last few months.

“Olivia Odendahl, 26, who shares a Lakeview two-bedroom walkup apartment with a roommate, saw her July 18 ComEd bill more than double month-over-month to $120.83.”

Source: Chicago Tribune - ComEd supply rate bill increases

It's been a hot few months, of course, and we're all used to electric bills being higher in the summer. But this year, that's only half the picture.

The story behind the price increases is surprisingly complex, but much of it can be told with just three players:

• A costly coal plant
• A power-hungry data center
• PJM

Never heard of PJM? That puts you firmly in the majority of people. In short, they're the largest electric grid operator in the US. And also, unfortunately, your grid operator, because as it turns out, PJM is the real cause of our electric rates going up.

But we'll get to all that. Our story begins not with the mysterious PJM but with plain old, all-too-familiar coal.

Player one: the costly coal plant

The role of the coal plant in this story is a simple one: it's powering down.

For half a century—from the 1950s to the 2000s—roughly half of all US electricity came from coal. The reason for this is just what you'd expect: it was cheap. (Cheap, that is, as long as you ignore its externalities.)

It's for just those same economic reasons that coal plants across the country are shutting down. When it comes to cost, coal has become the expensive option. It isn't so much that coal itself has gotten more expensive, but that we now have substantially cheaper ways of producing electricity.

As a result, the US has been in the process of replacing coal power plants with more cost-effective options. At first this generally meant natural gas plants. But today—believe it or not—the cheapest source of new generation is renewables, led by solar and wind.

Source: Our World In Data - Levelized Cost of Energy

Ok, that's the rundown on the supply side. Now let's turn to demand.

Player two: the power-hungry data center

The data center in our story is here to play the role of electricity consumer, and not for no reason. Between 2023 and 2028, data centers are expected to account for close to half of all new demand on our power grid. ^*

^* While that could amount to more like 12% of total electricity, the grid works on marginal demand—new and unexpected demand strains supply.

So just as our oldest power plants are shutting down, data centers are ramping up—and fast.

While it might seem easy to simply blame data centers, in many ways, they're simply revealing a problem that was already there. The US has just emerged from a slumbering two-decade period of basically flat demand growth on an aging grid. Even without data centers, we would still need to modernize our grid to support a future that will be increasingly electric as we transition to efficient and clean technologies like electric vehicles and heat pumps.

Source: U.S. Energy Information Administration - Electricity Retail Sales
See more: US electricity demand will grow 50% by 2050... - Utility Dive

Which brings us to who that "we" actually refers to. Who's responsible for keeping the two sides of this equation balanced, ensuring that we have enough electricity to meet our growing demand?

That, in a nutshell, is the role of PJM.

Player three: PJM

Thought ComEd was in charge of our electricity? Well you're right. But that's not the whole picture.

Where ComEd serves as a sort of local distributor of electricity here in Chicago, PJM coordinates the transmission of power across a vast, 13-state region. If ComEd maintains city streets, PJM oversees the interstate highway system. They are what's known as a "grid operator."

It's PJM's job to ensure that there is enough total generation capacity (think: power plants) to keep the lights on across the region. Not just for tonight, but three years from tonight.

To make a guarantee like this in the face of all the uncertainties that "years out" entails, PJM and power generators make a deal. If generators promise to provide that electric capacity in three years, PJM will pay them a bounty for it.

This brings us to the crux of the matter—the immediate reason our electric bills just went up. That bounty, known as the "capacity price," has increased astronomically in the past two years—it's increased by over 1,000% (!!) This has a direct and visible impact on your electric bill—it shows up in the "supply" section of your ComEd bill.

This leads to the natural question: Why is this happening?

Part of the answer lies in the dynamics of the first two players: coal plants shutting down and data centers ramping up. But despite those dynamics, it 100% does not need to be this way.

The fundamental challenge we're facing is insufficient supply for our rapidly growing demand. The obvious solution to this problem also happens to be the correct one: increase the supply!

Unfortunately, it's here that PJM is falling disastrously short. PJM is the slowest of all grid operators in the US at getting new electricity generators onto the grid, with new energy sources waiting an average of 5 years to connect.

In a report on how the seven major grid operators in the US are handling this, PJM came in dead last. Its overall grade was a D-.

How renewables can help with energy prices

Solar and wind are now cheaper than coal. They're cheaper than nuclear. They're even cheaper than natural gas.

This shift has happened so quickly that very few people seem to appreciate it. Just 10 years ago, solar and wind were the Whole Foods of energy—nice if you can afford it, but you probably can't.

In just the last few years they have, somewhat miraculously, transformed into the Costco of energy: cheap, abundant, and shockingly high quality.

This is reflected by the makeup of the new generators waiting to get onto the grid. Fully 95% of them are solar, wind, and battery projects.

Cheap renewable electricity generation is ready and waiting to connect to our homes and businesses. Our task now is to force open the floodgates.

How you can change the story

If you want to add your strength to this effort—to stop rising power bills and very literally save the planet at the same time—choose your weapon.

All three of these actions are quickly done but calibrated to have maximum impact on the next chapter of this story.