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Hybrids a "stopgap", researchers say

Discussion in 'Prius, Hybrid, EV and Alt-Fuel News' started by Tideland Prius, Feb 8, 2008.

  1. Fibb222

    Fibb222 New Member

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    Finman, the author of the pdf you provided is interviewed in this article here:
    Why a hydrogen economy doesn't make sense
     
  2. miscrms

    miscrms Plug Envious Member

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    My personal favorite:
    http://www.hydrogen.energy.gov/docs/cs_central_coal_gasification.doc

    DOE study says Hydrogen fuel cell vehicles are currently less efficient than hybrids, but may be ~25% better than 2005 hybrid by 2030! Also claims they are cleaner, but only with carbon sequestration (which doesn't really exist on a production scale yet).

    Meanwhile if you do the numbers, the late 90s BEVs are much more efficient. More like equal to the 2030 fuel cell on the the currently operating ~30-40% efficient out-dated power plants. ~2x as efficient when using modern combined cycle power plants. Approaches ~3x more efficient when you go to harvested energy sources such as wind, solar, hydro particularly when local & decentralized. And thats all on 10 year old vehicle technology.

    BTU/mile "well to wheels"
    2005 Gas ICE: 5900
    2005 HEV: 4200
    2005 FCV: 5100
    2030 FCV: 3200

    1999 GM EV1 NimH Grid-to-Wheels: 373Wh/mi = 1273 BTU/mi
    Current Grid Well to Wheels (30-50%): 2546-4243 BTU/mi
    Combined Cycle W2W (59-85%): 1498-2157 BTU/mi
    Harvested W2W (95-99%): 1285-1340 BTU/mi

    A Prius is generally estimated at about 250 Wh/mi, and a modern charger should be able to get 80-90% efficiency. That would give a grid to wheels efficiency for a PHEV Prius of ~294Wh/mi. Assuming a 50% duty cycle between Gas and Electric:

    2010 PHEV Prius Est Well to Wheels:
    Current Grid: 3182-3903 BTU/mi
    Combined Cycle: 2736-3017 BTU/mi
    Harvested: 2646-2669 BTU/mi

    So PHEV using all current technology could easily be more efficient than the projected 2030 fuel cell :confused: Bear in mind these numbers are all for coal gassification, which is a considerably more efficient way to get Hydrogen than the electrolysis everyone assumes we'll use. (All you need is water, and its like free gas with no pollution, right?)

    Rob