3M's PFAS exit killed the supply chain for two-phase immersion cooling in DCs

On July 1, 2026, a law takes effect in Germany that no other major data center market has attempted at this scale. Any new data center commissioned on or after that date must reuse at least 10% of its waste heat. By 2027, the threshold rises to 15%. By 2028, 20%. Miss the target and the fines start at EUR 50,000, climbing to EUR 100,000 depending on the violation.

The law is called the Energieeffizienzgesetz. The German Parliament passed it in September 2023. It took effect in November of that year. And for most of the time since, the data center industry has treated it like something that would sort itself out before the deadline arrived. The deadline arrived.

On December 20, 2022, 3M announced it would stop manufacturing all PFAS chemicals by the end of 2025. That single decision vaporized the supply chain for two-phase immersion cooling in data centers. The fluids that made the technology possible, Novec 7100, Novec 649, Fluorinert FC-72, are gone. The last day to place a new Novec order was March 31, 2025. Manufacturing lines shut down by year's end.

3M did not make this call because they found a better product. They made it because they were staring down over 4,000 lawsuits and a $12.5 billion settlement with more than 11,000 U.S. public water systems alleging PFAS contamination in drinking water.

The number that dominates the data center water debate is wrong. Not wrong in the sense of inaccurate. Wrong in the sense of incomplete. When people talk about data center water consumption, they picture cooling towers on a rooftop evaporating thousands of gallons an hour. That is real. That happens. And it accounts for roughly 28% of the total water footprint.

The other 72% happens off-site. At the power plants generating the electricity that these facilities consume around the clock. Bluefield Research published these figures in late February 2026 in a report titled "The Water-Power Nexus." The numbers reframe the entire conversation.

The Global Water Table Is Collapsing. Data Centers Are Drinking Faster.

A United Nations report published in March 2025 introduced a term that should unsettle anyone building cooling infrastructure: "global water bankruptcy." The language is deliberate. According to the UN University's Institute for Water, Environment and Health, the world has moved past water stress and past water crisis into a condition where accumulated damage to freshwater systems has become, in many regions, irreversible. Half of the planet's large lakes have lost water since the early 1990s. Seventy percent of major aquifers are in long-term decline. Dozens of major rivers no longer reach the sea year-round.

Against that backdrop, the data center industry is scaling water consumption at a rate that would have been unthinkable five years ago. A large hyperscale data center consumes roughly 300,000 gallons of water per day. Facilities running dense AI workloads push that figure to 5 million gallons daily. Google reported approximately 6 billion gallons consumed by its data centers in 2024. Microsoft hit 1.69 billion gallons in fiscal year 2024, a 34% year-over-year increase driven almost entirely by AI infrastructure expansion.

120 Kilowatts Per Rack and Rising: Why Liquid Cooling Became Mandatory for AI Infrastructure

There is a clean line in the thermal management timeline. Before 2023, air cooling worked for the overwhelming majority of data center deployments. Standard server racks generated 7 to 15 kilowatts of heat, and a well-designed hot-aisle/cold-aisle configuration with precision air handlers could manage that load without breaking a sweat. Literally.

Then AI training clusters showed up at 40, 60, 85 kilowatts per rack. And now the next generation of GPU-dense cabinets is pushing past 120 kW, with designs on the board targeting 200 to 250 kW. Air cooling hits a hard physical ceiling around 25 to 30 kW per rack. The liquid cooling market has responded accordingly. BIS Research pegs the global market at $3.93 billion in 2024, growing to $22.57 billion by 2034. Goldman Sachs projects that 76% of AI servers will be liquid-cooled by the end of 2026, up from 15% in 2024. A fivefold increase in adoption in two years.

Nevada Banned Evaporative Cooling for Data Centers. Other States Are Watching.

In 2025, Nevada became the first U.S. state to ban evaporative cooling in new data center construction. The decision was not symbolic. Nevada sits in the driest region of the country, relies heavily on the Colorado River system (which has been in sustained decline for over two decades), and had watched a cluster of hyperscale data center proposals land on its doorstep, each one requesting municipal water allocations that would have supplied thousands of homes.

The state said no. Not to data centers entirely. To the specific cooling technology that consumes the most water. California followed with SB 58, a disclosure law requiring data centers above a certain capacity to report their water consumption publicly. Several other states have water reporting mandates in various stages of committee work. The European Commission announced minimum water performance standards for data centers that will take effect in 2026. The regulatory direction is clear. The only variable is speed.

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A growing number of data center operators have started swapping water-cooled systems for air-cooled alternatives, claiming sustainability wins. The math tells a different story. Air cooling eliminates on-site water use, sure. But it doubles or triples electricity consumption, pushing the water burden upstream to power plants that need their own cooling loops to generate that extra juice. The problem doesn't vanish. It moves.

Colocation vacancy rates have cratered to 2.3%, down from 9.8% in 2020. The construction pipeline grew tenfold over the same period. Every new facility that comes online has to make a fundamental call on how it manages heat, and that decision ripples through local water tables and power grids for decades. A large data center drinks roughly what a town of 50,000 people does in a day. Regulators in multiple states have started blocking projects over that kind of draw.

True sustainability means refusing to solve one problem by creating another. The operators who claim green credentials while tripling their grid draw are playing an accounting trick, not running an efficient facility.