USA, New York
Metropolitan Transport Authority (MTA) Long Island Bus has developed what MTA and New York Power Authority officials say is a more environmentally friendly bus fleet that is also the nation’s first commercial user of sodium-sulfur battery technology. The system takes electricity from the power grid at night, when rates are lowest, and stores it to power natural gas compressors the following day at the Mitchel Field depot in Garden City, LI.
MTA Long Island, which operates 220 CNG buses, began working with the power authority on this project three years ago, and started using it commercially on buses in April 2008. “It charges in an off-peak period and fuels when it is more efficient to do so, which gives clean air for everyone,” said Joseph J. Smith, president of MTA Long Island Bus. Smith said he hopes that using the technology will “have the power to make major changes in the transportation system in this country.”
Before MTA Long Island Bus adopted the system, employees operated the natural gas compressors at night to take advantage of lower rates. But now, storing the energy at night and using it during the day eliminates the need for a night shift, which slashes labor costs for the company by about $220,000 annually, officials said. MTA Long Island Bus estimates that using sodium-sulfur batteries saves $26,500 per year on their utility bills, too.
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