WFM? As previously discussed here I think, 10mn refill wouldn't be done at the average Joe's house, where recharging in a few hours would be sufficient. Fast charging would be for filling stations, which would need not only big "pipes" from the utility, but most probably also a hefty local storage (fixed batteries) in order to smooth out their power requirements over the day.
Michel 2008/10/18 Stephen A. Lawrence <[EMAIL PROTECTED]>: > > > Jones Beene wrote: >> Alternate subject line: "Volt gets shocked" > >> http://www.huliq.com/3169/70554/byd-launch-all-electric-car-h2-2009 >> > > Thanks; WFM. Cool story. Quick excerpt: > >> This F3DM hybrid combines hybrid and electric vehicle systems, with a >> 110km pure EV range. BYD said they can be recharged to 50% of >> capacity in just 10 minutes. > > Say what?? 10 minutes?? How you do that, pull up at a local ConEdison > substation and hook into a bus bar? > > Let's see how plausible it is to provide the power needed to charge it > that fast. > > Range 110 km. 50% charge => 50 km. Let's say that's at 20 hp draw from > the motor, traveling at 45 mph (which is kind of the standard speed for > finding mileage IIRC). > > At 20 hp from the motor, you're drawing about 15 kW from the batteries. > > At 45 mph = 72 kph, 50 km gives us a drive time of 0.7 hours, or a total > power consumption of just over 10 kWH. > > Recharging in 10 minutes, or 1/6 hour, implies a recharge rate of about > 60 kW. > > At 230 volts that would be 260 amps. > > OK, that's not as bad as I expected -- it could be done on residential > power, at least in some places, and if you could pull it directly off > the pole out at the street -- but it's still out of reach of the average > Joe's house wiring, which can typically deliver no more than 200 amps > total at the fuse box. > > Of course I didn't include the inefficiencies, if any, which may result > from hitting the battery pack with a very fast charge. > >
