Water Cooling Towers

Two, four-story water tanks behind the MagLab hold between them 16.3 million liters (4.3 million gallons) of water — the equivalent of about six and a half Olympic-size swimming pools. But you might not want to swim in them — the water is kept at 4.4 degrees Celsius (40 degrees Fahrenheit).

The volume of water in the tanks never changes; its purpose isn't to water gardens or fill bathtubs, but to store thermal energy and make cold water available at a moment's notice. Warm water enters at the top of the tank; cold is dispensed from the bottom. (Because this water does not come into contact with the magnets, it's regular ground water — ions and all. The chilled water we flush through our resistive magnets is deionized water.) If only one smaller magnet is in use, these tanks are sufficient to keep the system cool. But with multiple or bigger magnets, the chillers kick in.

By Kristen Coyne