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Who Killed the Electric Car?


JDC

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I don't think the power grid in the early 20th century could have sustained the demand electrics would have caused. It couldn't sustain even 10% of all cars on the road being electric now.

I keep hoping that electrics will get better, but the internal combstion engine has huge advantages over electrics.

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I'm not sure the electric car is practical right now. The problem with environmentalists is they want everything for nothing. Electric car means more electricity, which means more generation since most systems are nearly overloaded as it is. Of course, you need fossil fuels or nuclear for that, as solar and wind are just not practical right now.

So, on to hydrogen. While I don't really like the idea since I don't want to drive around with a high pressure bomb in my car, hydrogen could possibly be made using power on large systems during off-peak hours. Nuclear and coal plants take days to turn on and off, and as such, are not turned off at night. This excess power could be used to generate hydrogen while having little impact on the grid. Possible, but improbable.

Ethanol + ICE's. Personally, I like the ICE. Its really not that bad, and ethanol engines make more power than gasoline engines if they are designed to utilize ethanol. Using ethanol on a normal engine will make less power than gasoline. However, while a gasoline engine usually uses a compression ratio somewhere in the range of 9-10:1 to prevent detonation, an ethanol engine can go as high as 16:1, though 14:1 is a safer number. I have a dyno program that estimates engine power with certain parameters. Keeping everything in the engine identical except fuel and compression ratio, the gas engine makes 340HP and 328ft-lbs torque at 9:1 compression. The same engine at 14:1 compression and ethanol makes 410HP and 395ft-lbs of torque. Which means you can lower engine size and fuel consumption by sizing the engine to still make 340HP or whatever you want. The downside? Well, you will need strong, probably forged components to support the compression, which will slightly increase costs.

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You're on the right track about the compression ratios, but ethanol actually has less power per gallon. Also, you have to add this to your dyno program.

Smurf is right, though. To get the most from ethanol, you must take advantage of the reduced propensity to detonate by increasing compression ratio, or super/turbocharging the engine.

My big problem with ethanol is that I don't think it is wise to burn food in our cars.

Hydrogen causes problems with engine lubrication, and thus engine life. BMW's hydrogen powered 7 series has a projected life span of 70K miles. Compare that to 200K for a regular 7 series. How much do you think two BMW engine rebuilds will cost?

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OK, so it's the best alternative for the moment given the present crcumstances.

What do you see replacing it and when do you see that happening? Barring cheap fusion power making cheap electricity and thus the electric car viable, I don't see the ICE being replaced as the motive power for personal vehicles in the next fifty years.

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OK, so it's the best alternative for the moment given the present crcumstances.

What do you see replacing it and when do you see that happening? Barring cheap fusion power making cheap electricity and thus the electric car viable, I don't see the ICE being replaced as the motive power for personal vehicles in the next fifty years.

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Your post could have been made of 50 years ago and been relevant. You'd think in 50 years we would have put some effort into making something better. Given effort, yes, I believe a full electric car or a solar car could be a viable alternative. We can put someone on the moon but we can't figure out how to make a better car? Please....
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As a side note on the solar, the average car outputs somewhere in the 150HP neighborhood. That is equal to 111,800W (111.8kW). At 100% efficiency, getting 900W/m^2, you'd need an area of 124m^2, which is roughly equal to covering the roof of 3 semi-trailers or the floorplan of you average sized house (1334ft^2) with solar panels just to run your car. Slightly impractical, no? Solar is merely a token energy source, it makes environmentalists happy, lets power companies write off a few million dollars but basically does nothing. The only real use for solar IMO, is heating water. Not using solar for electricity, but using it to heat water, which can serve as domestic hot water or be used in environmental controls. You want to really save the environment, go read my thread about Inductive Power Transfer (IPT) and Water-To-Water Heat Pumps (WTWHP).

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Keep in mind that 150hp is far far more than is needed to actually operate the vehicle. I've driven cars with a 40hp motor ('65 VW bug), and 60 hp motors ('71 VW van and '80 Toyota Tercel). High HP is only useful for fast acceleration and high speeds (above 75 mph). The characteristics of an electric motor are quite different than that of a gasoline engine, I would say that you could build a reasonable electric vehicle with something on the order of a 25 - 40 HP motor and even that would be a lot.

Are you going to build a solar vehicle that can match the specifications of a gas guzzler? Probably not. Could you build a solar vehicle that could be used for more modest travel. It's very possible. Especially if you supplemented the charging with plugging in with AC from time to time. Solar would make a completely electric vehicle much more viable.

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Also, remember those low HP motors were in smaller cars than generally used today. Cars are safer, but as a result, weigh much more. If it takes me 30 sec to reach 60mph, no one is going to be satisfied. Balancing performace and power is the challenge. However, even 25HP is 18.6kW. Again, at 900W/m^2, thats roughly 8.3m^2, or 90ft^2, a 9ftx10ft area. Still too much area for a average sized car. Also remember, 900W/m^2 is 100% efficient. At best, you might get 40% in the summer, maybe 25% in the winter, and as little as 10% during cloudy days. Solar is just not a viable alternative for anything electricity related. An electric motor does work differently, since is produces maximum torque at 0rpm, so initial acceleration would be decent, but beyond that it would be diminishing returns. On the other hand, ICE's produce more torque as rpm's increase, leading to increasing rates of acceleration.

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There is something called a battery and a capacitor. You don't need to generate 25 hp in solar energy constantly. The car will be generating and storing energy while sitting in parking lots or stuck in traffic.

In terms of HP, most cars of the world have far less HP than the vehicles in the USA. I will point out the 40HP VW Bug would weigh more than most similar sized vehicles on the road today. Modern plastics and composites have made this possible. The VW Bug was the 2nd most popular vehicle in the world of all time. Not bad for a car that was sold with engines that small.

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^ Good point.

But at 746 watts/hp and 300w/sqaure meter practical cell output, it'd still be a pretty big cell array.

Back in the 70s, the Navy was working on a carbon matrix to store vast amounts of heat energy in a small package. I wonder whatever happened to that project.

I had a bug in college and loved it, but 25 second 0-60 times and no safetey features just don't cut it with consumers anymore. At least not in quantities that would make it a viable business proposition.

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I could almost/maybe see an electric car selling a thousand units or so a year if it was basically a four or three wheeled motorcycle. No heat/ac/wipers with LED headlights. Keep it under a ton, give it a 100 mile range, 0-60 in six seconds, and I think the hard core enthusiasts might buy one.

When I worked in vehicles for the Air Force, we got an electric Dodge Dakota as part of a clean energy initiative back in the early 90s. The base commader wanted to take it to a country club where he was giving a speech on the Air Force's alternative energy program. Aware that the truck had a 25 mile range and the club was 12 miles away, the program manager took the truck over there and back to make sure it could make it OK. It did, although he said it was kind of dragging the last mile or so.

This was a warm, cloudless day.

The day the general drove the truck, it was cold, wet and raining. As a result, the lights, widsheild wipers, heat, and AC (for defrosters) were running. The truck died two miles from the country club.

The general was not happy.

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  • 1 month later...

Check out an electric sportscar that goes 0-60 in 4 seconds, has a top speed of 130 mph, and has a range of 250 miles, much farther than any previous electric car.

tesla motors

This company plans on offering a 4 door sedan next year at a lower price. With some more improvement in range, this could be a major comeback for the electric car.

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  • 4 months later...

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