How the Microsoft-Three Mile Island deal impacts Pennsylvania, AI and the economy

Three Mile Island hopes to turn around its reputation, from former disaster site to green energy powerhouse — and it has a big-name partner on board to help. 

Constellation Energy, the company that runs the Londonderry, Pennsylvania-based plant, announced on Friday its “largest ever power purchase agreement” in a landmark deal with Microsoft. 

The energy firm will sell the nuclear power generated from the recommissioned plant to the tech giant specifically to fuel its processing-heavy AI systems. 

To get it ready for production, Constellation, which is headquartered in Baltimore, Maryland, will pour $1.6 billion into upgrading the infrastructure. The overhaul, it hopes, will pay off in economic impact and a commitment to more sustainable energy sources. 

“[Three Mile Island] has always been a positive community partner who provided jobs and commerce as well as support for area nonprofits so we welcome them back,” said David Blechertas, Londonderry Township manager. “The development of infrastructure is a boost to the area and will positively impact the local economy.”

The plant, located in Dauphin County in south central Pennsylvania, will reopen 2028, as a part of the Crane Clean Energy Center (CCEC) initiative to introduce more carbon-free energy sources into the area with ambitious economic outlooks. 

After 20 years of operations, the plan could increase state gross domestic product by $16 billion, create 3,400 new jobs and bring in $3.6 billion in tax revenue, per a report by the Pennsylvania Building & Construction Trades Council.

“This is a valuable opportunity to invest in clean, carbon-free and affordable power —on the heels of the hottest year in Earth’s history,” said Pa. Rep. Tom Mehaffie, whose district includes Three Mile Island. “This will transform the local economy and presents a rare opportunity to power our economy with reliable clean energy that we can count on.”

Constellation Energy did not disclose financials of the deal. 

AI burns through resources, sparking environmental concern

Tech companies use up massive amounts of energy on data processing, including to run the AI programs that have grabbed attention in the last few years.

Studies continue to come out about just how much the emerging tech impacts our planet. It’s a pattern we previously saw with cryptocurrency.  Plus, there are the massive data centers around the country, including “Data Center Alley” in Virginia, that make up about 2% of the nation’s energy usage. 

But more tech companies have big plans to reduce their impact. Microsoft, which calls its generative AI tool Copilot, still says it aims to be carbon neutral by 2030.

“Microsoft continues to collaborate with energy providers to develop carbon-free energy sources to help meet the grids’ capacity and reliability needs,” Bobby Hollis, VP of energy at Microsoft, said in a release.  

Microsoft declined Technical.ly’s request for further comment. 

There are two main ways AI drains processing power: Training its algorithms of massive quantities of data and run-of-the-mill use after the fact. 

Estimates vary on how much but, for example, training ChatGPT-3 consumed 1,300,000 kilowatt hours (kWh) of electricity, according to the Verge. Running 1,000 written tasks on the generative AI model uses between 0.002 kWh and 0.047 kWh, while the same number of image-generated tasks averages 2.907 kWh. 

For comparison, the average US home burns through 899 kWh per month, according to the US Energy Information Administration. 

In 2023, ChatGPT had 100 million monthly active users. If every user completed just one task per month, not including training, it would consume 200 kWh to 290,700 kWh, according to some rough math. 

That range is so large because the numbers vary greatly between image and text generation, so it only represents the two extreme scenarios. Still it’s safe to say: That’s a lot of energy consumption. 

Three Mile Island’s Unit 1 could generate 837,000 kilowatts at once before it shut down in 2019.

Three Mile Island pushes back against ‘disaster’ reputation 

Despite the enthusiasm from some local legislators, Three Mile Island is still mostly known for the 1979 accident.

The most serious accident in US commercial nuclear power plant operating history occurred after a blockage in the Unit 2 reactor that caused a core meltdown. Operators permanently shut down Unit 2 after the incident. The nearby Unit 1 will be the source of energy generation for the Constellation-Microsoft deal. 

Still, the incident exposed about 2 million people in the surrounding area to small amounts of radiaiton, according to the federal Office of Nuclear Energy. 

The amount was so minimal, however, that studies since the incident found no evidence of increased infant mortality or cancer rates among those living near or downwind of the plant, according to nuclear research center Idaho National Laboratory. 

“Thousands of environmental samples of air, water, milk, vegetation, soil and foodstuffs were collected by various government agencies monitoring the area,” the US Nuclear Regulatory Commisssion (NRC) writes. “Very low levels of radionuclides could be attributed to releases from the accident.” 

It did, however, catalyze new regulations and guidelines around the use of nuclear energy. Stronger design and equipment standards, better emergency preparedness, expanded inspector programs and more all took shape after the meltdown. 

For now, the next steps are in Constellation Energy’s hands, according to Scott Burnell, public affairs officer at NRC.

“It’s up to Constellation to lay out its rationale for justifying restart, so we’re prepared to engage with the company on next steps,” Burnell told Technical.ly. “The NRC will use existing review processes to consider any licensing requests needed to restore a decommissioning plant to an operating status. When the agency accepts a request for review, we issue timelines for completing our work.”