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gadget_lover said:
At the risk of sounding condecending, the problem with adding a charger to a hybrid is that the average joe can't seem to differentiate between the different modalities.
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That's fine but why can't the average joe be educated on the subject a little better? And why must everything always fall to the lowest common denominator even if they can't be? There are plenty of people who would buy into EVs right now if they were available. Once they were out there, you would have yet more. Since hybrids already have all of the requisite parts, I see offering all hybrids with an "electric only" option as a cost-effective way to make this happen right now. The fact is that our polluted cities especially would benefit greatly from a zero-emissions mandate, and electric-only hybrids are a good way to make this happen.
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I don't think I've seen a "state of the art" EV that seats 5 and has a 200 to 300 mile range. Which one was that?
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I'm talking about what could be made without even resorting to radical body designs. The fact that the automakers choose not to is because they would ultimately make less profit on a vehicle that only needs tires over its lifetime.
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How many charging stations would be needed to handle just 7 cars with a 15 minute charge each? In other words, to fill 7 cars every 5 minutes, how many chargers does my station need?
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The point of home recharge is that not every user will be using the recharge station if they can recharge at home overnight, and more cheaply. My guess is that if every pump were converted to a recharge station there would be no problems even at peak capacity. Even if not, allowing two minutes to pull in/out and hook up plus 15 minutes to recharge, I get 24 recharge stations. Get the recharge time down to 9 minutes, and you only need 16 stations.
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getting back on topic... In essence, the current hybrids are a good way to get the public used to a different way of doing things, and are an excellent stepping stone to the next generation of EV or Plug in hybrids. You just have to get the average joe used to one thing at a time.
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But why must those who are ready for EVs right now wait another ten or twenty years for the average joe to catch up? If fact, now that they're pushing fuel cells as a long term solution then EVs might never happen. What will happen is that fuel cells will probably never be feasible or make sense since a battery is always better from a pure efficiency and ease of use standpopint, and then we'll be left with the same old ICE in twenty years, perhaps with a hybrid twist to it. It is really that hard to uncondition people to the idea of using liquid fuels and also to accept "quiet" vehicles as powerful? Look how fast the average joe adopted PCs once they saw the advantages. They went from being something that only nerds have ten years ago to being virtually ubiquitous nowadays. My guess is we could do likewise with EVs with a proper reeduation campaign.
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P.S. A 1000 mile trip on 20 kwh would be fantastic. That's 20 wh per mile, which is 10 times better than the best figures I've seen. I'd like to see the math for the Cd and frontal area for a car big enough for two people to sit in (not lay) side by side.
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I'll use realistic speeds here instead of the 10 mph often used to showcase these ultra-long range EVs. First of all I base this on a 30 kW-hr capacity which is realistic with current battery technology (the 20 kW-hr came from the post before mine, but I think 30 kW-hr is typical of EVs these days). 30 w-hr per mile = 2400 watts @ 80 mph. Let's allow 90% losses so we get 2160 watts or 2.9 HP at the wheels. 2.9HP @ 80 mph equals a propulsive force of 13.6 pounds. Let's assume 1500 pounds weight and a rolling coefficient of 0.0035 (about the best we can do with rubber tires). This gives us 5.25 pounds for rolling resistance, leaving 8.35 pounds for aero drag. For frontal area we'll assume 15 ft² (about the smallest you can go for two people side-by-side without resorting to unnatural seating positions). This frontal area requires a drag coefficient of 0.036. This is just on the edge of possible. Remember that I purposely choose a realistic speed (80 mph seems to be what the median speed is on most rural highways these days). If you want to cut the speed down to 60 mph, then we only need a drag coefficient of 0.064. This is quite doable. Also, if you lose the requirement that the people sit side-by-side and instead sit one behind another, you can have a Cd of 0.072 @ 80 mph or 0.128 @ 60 mph. Either are quite feasible, especially the later.
I'll grant that I may be pushing the envelope here, but longer term (probably within a few years) we'll have 100 kW-hr batteries which are physically the same weight and size as today's batteries. Doing the calculations again for 100 kW-hr and 80 mph requires a Cd of 0.174. We had cars with Cds this good 60 years ago (I forgot the name). You can even up the speed to 100 mph and you get a Cd of 0.111 (still very doable) if you want a 1000 mile range. Research into laminar flow (which increases with velocity instead of velocity squared) may eventually enable even more efficient body designs without sacrificing comfort or drivability. Remember that we have already made a vehicle that can reach 81 mph with only a 1 HP human motor. I personally feel we'll eventually break the century mark under human power alone. The implications for vehicle design are staggering if this research is put into practice.