World's First Big MagLev Chillers Installed
Mar 21, 2007
 Print this page

The world's first large-tonnage magnetic levitation bearing (maglev) air-cooled chiller for air-conditioning, from chiller OEM Multistack, is being installed in the American Embassy in Tokyo. The technology demonstration project will be brought on-line in April, coinciding with the Tokyo Sakura Festival.

"We see this as the bellwether project in the U.S. State Department's ambitious worldwide effort to reduce embassy electrical energy consumption, especially in air-conditioning systems," said General Charles E. Williams, director and chief operating officer of the U.S. State Department's Overseas Buildings Operations (OBO). "Japan's progressive energy and technology policies were central to selection of the American Embassy Tokyo."

OBO is installing a 2,520-kW (720 tons of cooling) air-cooled chiller plant, consisting of twelve 210-kW MagLev Chiller modules on the roof of Embassy. Multistack, LLC of Sparta, Wisconsin, U.S. manufactures the MagLev Chiller, and said it is so confident in the technology that it warranted replacement of the MagLev units with new, conventional chillers in the event OBO is dissatisfied with them.

OBO Senior Mechanical Engineer Antonio Rivera, project manager for the Energy Technology Demonstration Project, said the project will cost about U.S. $2.8 million, but the premium paid for the new technology will be recovered in less than 10 years. "The MagLev Chiller's 'greening of the Embassy' will dramatically reduce Embassy electrical consumption and demand charges," Rivera said. "It also eliminates the Embassy's largest source of water and sewer costs. The air-cooled MagLev chiller eliminates disposal of biocide and corrosion control chemical waste and waste water from cooling towers."

While the promise of virtually frictionless, oil-free, active magnetic bearings (e.g., a maglev compressor) has been around since the 1940's, reliable electronic control for maintaining a motor shaft within required microscopic tolerances was not available until recently. Today's nanosecond-fast semiconductor devices have overcome the maglev shaft-centering challenge.

Energy performance results will be monitored by Multistack for 1 year and will be available on the Multistack Web site at: and the Embassy Web site at

Back to Breaking News