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Ford Pulls The Plug on Electric Cars
Cytos writes "Apparently Ford has called it quits on their EV program Th!nk Mobility, stating "... we don't believe that this is the future of environmental transport for the mass market." Ford had purchased Think in 1990 and did a short run of advertisments in California for it's lease trial, even involving Hertz in helping out. I was really hoping to see this pan out, I guess our only hope for an EV now is the Toyota Rav4 EV." From the sound of it, most companies are looking at hybrid cars.
2. Can be charged/refilled in many ways - including a fast charge at some type of service station. Also, a fold out/attachable solar array (maybe folds out of trunk, or from underneath the car). It must be able to be charged to at least 2 hrs worth of driving in the same amount of time as a normal "fill up". Absolute longest is five minutes.
Sorry, this is almost impossible. You underestimate the tremendous energy density of gasoline. To move an equivalent amount of electical energy in such a short time would probably require conductors too heavy to lift, and refueling stations would require special high capacity hookups to the electrical grid.
Gasoline has an energy density of about 44 MJ/kg, and a density of 740kg/m^3. Let's assume you put 15 gallons into your tank in five minutes (which would be a pretty slow gas pump if you ask me.) That's 1.85 GJ of energy! Now, certainly not all of that energy is put to use moving the vehicle. Most of it goes to the atmosphere as heat. Let's say 20% of it does useful work. (Or, alternatively, that electric vehicles are 1/.2 or 5 times more efficient.) That means that our electric vehicle needs 370 MJ of energy for the equivalent fillup. If you want that in 5 minutes, you're looking at a rate of 1.23 MW (that's megawatts!) At 120 Volts, that would be over 10,000 amperes. Even at at 10,000 Volts, that's still 123 amperes.
It requires either extremely high current or very high voltage to move that much electrical energy that fast. Neither is practical -- that much current would be horribly inefficient unless you had a cable the diameter of your leg. The notion of very high voltages at filling stations is no better. This completely ignores the fact that the "system voltage" of the vehicle is probably around 75 - 150V, so this refilling voltage would have to get stepped down again, and you're back to the problem of how to handle 10,000 amps. And of course there's the fact that the electrical grid probably could not handle short bursts of several megawatts for every person refilling a car. How many simultaneous people are refilling their cars at any given time? And how much extra headroom does your power company have?
This is one of the classic problems of the all-electric vehicle. I don't think you'll ever see charging times reduced to less than 4 - 6 hours. And that's for specialized refilling stations. Most households just aren't wired for anywhere close to that much power. Older houses I think had 150 amp service, newer houses are built to 200 or 250 amp service, if I recall.