Large volumes of freshwater are needed to operate evaporative cooling systems in nuclear and fossil fuel-fired power plants. Much of the water is eventually lost as fog and vapor, prompting MIT engineers to devise a way to recover this resource and reduce plant operating costs.

The water collection system imparts an electrical charge to water droplets by use of an ion beam, after which droplets pass through wire meshes that have the opposite charge. The water drained into a collecting pan can then be reused in the power plant or used to augment municipal water supplies.

The system was observed to eliminate water vapor plumes and yield high purity water when tested at a natural gas-fired cogeneration plant on campus. Additional trials conducted at an MIT nuclear research reactor also proved successful, demonstrating complete plume removal under more stringent real-world test conditions, and producing water 100 times cleaner than the incoming cooling system feedwater.

Infinite Cooling, an MIT spinoff formed to advance and commercialize the technology, will soon install the water collection system at a 900 MW power plant and at a chemical manufacturing plant. The developers expect the system to reduce the water requirements for power plant operators by up to 20%.

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