----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, September 03, 2002 6:10 PM Subject: EV Newbie -- 3
> Ok, I've pondered the previous emails, and pulled some info off > http://www.baaction.org/ev_project/batteries_1.html which seems to make > sense, though there is one "mystery" number I'd like you to ponder. > > First, here are some amp hour specs for Trojan 6 volt batteries: > > T-105 217 (20-amp hour rating) > T-125 235 (20-amp hour rating) > T-145 244 (20-amp hour rating) > > And here's the amp hour conversion factor provided by Trojan for a one-hour > rating, which should be used because of the faster draw of current when the > batteries are used in an EV: > > X hr Conversion rate factor > 1 hour rate is multiplied by .57 > 2 .67 > 3 .74 > 4 .77 > 5 .82 > 6 .84 > 7 .86 > 8 .87 > 9 .89 > 10 .91 > 20 hour rate is multipled by 1.00 > > So, a T-105, rated at 217 amps is really able to produce .57x217=124 amps at > an EV one-hour rate. > > So, if I have a 120 volt battery pack of T-105s, I multiple 120x124 and get > 15,500 watts, or 15.5kW (VxA=W) of power on a fully charged battery pack. This is good stuff, not to be picky but kwH (H for hours) am I right hear? > Now comes the mystery formula. According to the website, a Geo Metro using a > DC motor will use about 200 Watt hours per mile at 60mph. This number > supposedly came from a series of tests. Can anyone confirm/challenge? I'm a little slow here so would that be 200x60 1800w or 120v at 150 amps (poor batts) my porschs is a little better that that not much 3800lbs (slow down to 50 and save them amps) > Anyway, if I divide 15,500 watts by 200 watts/mile, I get a range of 77.5 with t-105 I don't think so > miles at 60 mph -- I assume this means the batteries are completly drained at > the end. you wiped them baby good I know that isn't a good idea, so I'll by .80, to allow .20 left in > the batteries, and get 62.24 miles on a full charge at 60mph, which seems to > be in the ballpark for EVs. Have you driven one (felt the magic)? > So, does this math look right? > > Now for the final question for tonight -- does all this mean that the vehicle > will be using energy at the rate of 200 watts per mile at 60mph? Is that an > appropriate way to look at the "fuel consumption"? In other words, once the > car reaches 60mph, it theoretically takes 200 watts per hour to keep it > going, assuming a flat road and no other external variables entering the > picture. Is that right? I have an EV story to tell would you like to hear? > As always, thanks for the help. > "There will be no need for war as we have greatly understamated the power of the Hood ornamant" Steve Clunn (lee are you still with me :-( > Bruce > Chapel Hill, NC > > "Dead fish go with the flow..." Anon. > >
