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Old 03-22-2011, 10:24 PM   #21 (permalink)
bwilson4web
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Location: Huntsville, AL
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Quote:
Originally Posted by roflwaffle View Post
The biggest problem w/ hydraulic hybrids in passenger vehicles is the weight of the accumulator. Even low weight CF accumulators still run about 240lbs for ~.3kWh of energy storage. A battery pack in something like the Prius is ~100lbs and has ~.7kWh of useful energy, so even low weight accumulators would clock in above 500lbs to get to the same amount of energy storage a 100lb NiMH battery pack has.
I would like to suggest the hybrid system has a substantially higher, peak power compared to the electric hybrid. So I'm thinking:
  • garbage truck - with very short, start-stop cycles with tons of mass to move and stop, use hydraulic hybrid.
  • passenger car - needing to climb the occasional hill with light mass, longer distances and substantial energy-to-mass changes, use electric hybrid.
I'm a "right tool for the right job" guy who believes there is more than one solution based upon the requirements. For a commuting car, light mass and a high ratio of commuting energy to mass, use electric (and plug-in.) For a big honker vehicle, hydraulic makes a lot of sense.

Bob Wilson

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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL
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