Artificial intelligence using huge volumes of water

The cost of building an artificial intelligence product like ChatGPT can be hard to measure. But one thing Microsoft-backed OpenAI needed for its technology was plenty of water.

That water is pulled from the watershed of the Raccoon and Des Moines rivers in central Iowa. It is taken to cool a powerful supercomputer as it helped teach its AI systems how to mimic human writing.

As they race to capitalize on a craze for generative AI, leading tech developers, including Microsoft, OpenAI, and Google, have acknowledged that growing demand for their AI tools carries hefty costs. Those costs range from expensive semiconductors to an increase in water consumption.

But they’re often secretive about the specifics. Few people in Iowa knew about its status as the birthplace of OpenAI’s most advanced large language model, GPT-4. This was before a top Microsoft executive said in a speech it “was literally made next to cornfields west of Des Moines.”

Building a large language model requires analyzing patterns across a vast trove of human-written text. All that computing takes a lot of electricity and generates heat. Data centres need to pump in water to keep it cool on hot days. It is often pumped to a cooling tower outside its warehouse-sized buildings.

In its latest environmental report, Microsoft disclosed that its global water consumption spiked 34 per cent from 2021 to 2022 (to nearly 1.7 billion gallons. This is more than 2,500 Olympic-sized swimming pools). This is a sharp increase compared to previous years that outside researchers tie to AI research.

“It’s fair to say the majority of the growth is due to AI,” including “its heavy investment in generative AI and partnership with OpenAI,” said Shaolei Ren, a researcher at the University of California, Riverside. He has been trying to calculate the environmental impact of generative AI products such as ChatGPT.

ChatGPT and language models use vast volumes of water

In a paper due to be published later this year, Ren’s team estimates ChatGPT gulps up 500 millilitres of water every time you ask it a series of between 5 to 50 prompts or questions. The range varies depending on where its servers are located and the season. The estimate includes indirect water usage that the companies don’t measure. This includes water used to cool power plants that supply the data centres with electricity.

“Most people are unaware of the resource usage underlying ChatGPT,” Ren said. “If you’re not aware of the resource usage, then there’s no way we can help conserve the resources.”

Google reported a 20 per cent growth in water use in the same period. Ren also largely attributed this jump to its AI work. Google’s spike wasn’t uniform. It was steady in Oregon, where water use has attracted public attention while doubling outside Las Vegas. It was also thirsty in Iowa, drawing more potable water to its Council Bluffs data centres than anywhere else.

Microsoft said in a statement this week that it is investing in research to measure AI’s energy and carbon footprint. It also said it was “working on ways to make large systems more efficient, in both training and application.”

“We will continue to monitor our emissions and accelerate progress while increasing our use of clean energy to power data centres,” said Microsoft in a statement. It would look at “purchasing renewable energy and other efforts to meet our sustainability goals of being carbon negative, water positive and zero waste by 2030.”

OpenAI echoed those comments in its own statement last week. It said it’s giving “considerable thought” to the best use of computing power.

“We recognize training large models can be energy and water-intensive” and work to improve efficiencies, it said.

Investing in artificial intelligence and data centres

Microsoft invested its first $1 billion in San Francisco-based OpenAI in 2019, more than two years before the startup introduced ChatGPT and sparked worldwide fascination with AI advancements. The software giant would supply the computing power needed to train the AI models as part of the deal.

To do at least some of that work, the two companies looked to West Des Moines, Iowa, a city of 68,000 people where Microsoft has been amassing data centres to power its cloud computing services for over a decade. Its fourth and fifth data centres will open there later this year.

“They’re building them as fast as they can,” said Steve Gaer, the city’s mayor, when Microsoft came to town. Gaer said the company was attracted to the city’s commitment to building public infrastructure. Microsoft contributed a “staggering” sum through tax payments supporting that investment.

“But, you know, they were pretty secretive on what they’re doing out there,” he added.

Microsoft first said it was developing one of the world’s most powerful supercomputers for OpenAI in 2020. It described it as a “single system” with more than 285,000 cores of conventional semiconductors and 10,000 graphics processors.

Experts have said it can make sense to “pre-train” an AI model at a single location because of the large amounts of data that need to be transferred between computing cores.

It wasn’t until late May that Microsoft’s president, Brad Smith, disclosed that it had built its “advanced AI supercomputing data centre” in Iowa. It was built exclusively to enable OpenAI to train what has become its fourth-generation model, GPT-4. The model now powers premium versions of ChatGPT and some of Microsoft’s products. It has accelerated a debate about containing AI’s societal risks.

“These extraordinary engineers in California made it, but it was really made in Iowa,” Smith said.

Plains of Iowa support AI but not efficient water use

In some ways, West Des Moines is a relatively efficient place to train a powerful AI system. This is especially compared to Microsoft’s data centres in Arizona, which consume far more water for the same computing demand.

“So if you are developing AI models within Microsoft, then you should schedule your training in Iowa instead of Arizona,” Ren said. “In terms of training, there’s no difference. In terms of water consumption or energy consumption, there’s a big difference.”

Iowa’s weather is cool enough for Microsoft to use outside air for much of the year. Only when the temperature exceeds 29.3 degrees Celsius (about 85 degrees Fahrenheit) does it withdraw water, the company has said in a public disclosure.

That can still be a lot of water, especially in the summer. In July 2022, the month before OpenAI says it completed its training of GPT-4, Microsoft pumped about 11.5 million gallons of water to its cluster of Iowa data centres. This was according to the West Des Moines Water Works. That amounted to about 6 per cent of all the water used in the district, which also supplies drinking water to the city’s residents.

In 2022, a document from the West Des Moines Water Works said it and the city government “will only consider future data centre projects” from Microsoft if those projects can “demonstrate and implement technology to significantly reduce peak water usage from the current levels” to preserve the water supply for residential and other commercial needs.

Microsoft said it is working directly with the waterworks to address its feedback. In a written statement, the waterworks said the company has been a good partner. Microsoft has been working with local officials to reduce its water footprint while meeting its needs.