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Old 09-14-2009, 06:09 PM   #2 (permalink)
EcoModding Lurker
Join Date: Jul 2009
Location: New Zealand
Posts: 13

Swift Sport - '09 Suzuki Swift Sport
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I think what say's it all is a quote from an article on the EPA / UPS's hydraulic hybrid system.

"Because of the added weight of the tanks used to store pressurized fluid in the system, the best application may be in heavy-duty trucks that inch their way through urban stop-and-go driving."

My somewhat limited engineering experience in hydrostatic system design tells me that overall efficiency is not all that high, but perhaps no worst than the cumulative losses encountered in electric hybrid battery charge/discharge and power conversion steps.

Either system needs computerized controls but the major difference is that the hydraulic system will be far cheaper for high-capacity systems. For a car the size of a Prius hydraulics is unlikely to be a better choice for a number of reasons, persistent oil leaks being only one of them.
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