Thread: Electric cars are a pipe dream

  1. #1201
    Please use Sugar Cane Alcohol Billy T's Avatar
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    Quote Originally Posted by McMurphy View Post
    ... (1) Can you explain how there can be a net reduction in CO2 through their use.
    I am not a big fan of present large-scale alcohol fuels development, due to the risk to raising the price of food production for the poorest. However (2) cellulotic biofuels are potentially a win-win if done well on low food-value land.
    On (1) The carbon in sugar cane alcohol in the various storage containers I already named was removed from the air. While any given carbon atom in storage will eventually be used as fuel it will be replaced by others, newly added to these storage tanks. Thus some CO2 has been permanently removed from the air. That will not prevent the huge burning of fossil fuels from causing the air's CO2 from increasing, but even replacing 1% of fossil fuels with sugar cane alcohol would be a step in the right direction.

    On (2) Un like corn, humans don't eat sugar cane but eat both the sugar and alcohol made from it. Both are among the lowest cost per calorie food that exists (until taxes are added). There is a huge amount of unused tropical land that could be growing sugar cane. The only real effect of using it on food prices would be that growing it would give more income to the really poor. - They might then increase their demand for foods so their children do not go to bed hungry every night. - That would indirectly increase the cost of food, but nothing like the US's silly use of corn for alcohol production does.
    Quote Originally Posted by McMurphy View Post
    ... The other reason I'm not over keen on Alco-fuels is the same (not conspiratorial) reason Big-Oil is against them - they are hard to scale up because they rely on biological processes that can be poisoned, etc.
    So does beer and that scaled up with few problems. Compared to the complexity of an oil refinery making dozens of different products and reformulating the raw crude differently with the seasons (more gasoline for summer driving and more fuel oil for winter heating etc.) a simple fermentation tank and still is so simple that even an illerate hill-billy can make alcohol. (When only 10 years old and living on farm near W. VA. / Virgina border I sold three bushels of shelled corn I had raised to one.)
    Quote Originally Posted by McMurphy View Post
    ... Can you see a future where 1000's of small scale producers make bio-diesel, or ethonol, or higher alcohols (like Butanol) for running fuel cells on, while the Oil-companies quietly die off? ....
    Yes, but no die off of oil companies. Because the feed stock of bio fuels have high bulk / low energy density they can not be transported great distances economically. That is why many smaller plant will b used, But at present there is no reason to be confident that making bio-fuel from these material (other than the crushed cane) will be economically competitive with cellulosic alcohol from crushed sugar cane. It has a tremendous cost advantage as it is already at the plant - you do not need to pay again to collect it from fields or transport it to the fermentation plant.
    Last edited by Billy T; 01-18-11 at 02:52 PM.

  2. #1202
    Quote Originally Posted by Billvon
    Any BEV that has to have a trailer attached to it all the time will be a non-starter
    You bet. For one thing, those batteries are very heavy. Lugging around a second one would be a tremendous energy drain in addition to greatly reducing the performance of the (already humbly performing) car.
    Quote Originally Posted by McMurphy View Post
    Interesting points about Alcohol fuels. Can you explain how there can be a net reduction in CO2 through their use.
    As he said, you have less transportation and storage because you're growing the crops in your own country instead of pumping it out of somebody else's country.
    Can you see a future where 1000's of small scale producers make bio-diesel . . . .
    That's already a cottage industry. People go to McDonalds and take away their used fry-oil. McD is happy to give it to them because then they don't have to pay to have it hauled away as garbage. It's a bit of a process to filter out the potato shards, and everywhere you go the pedestrians wonder why they're smelling french fries in the air (I'm not making this up), but it's become something of an elitist hobby for the greenies and it does save them a lot of money at $3.50 a gallon.

    I haven't tried it and my Mercedes mechanic insists that you can't run a diesel engine on corn or soybean oil without a little tweaking, but apparently these kids have overcome that obstacle.

  3. #1203
    Registered Senior Member Skeptical's Avatar
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    There is a very good way to use sugar cane alcohol (or other biofuels) to reduce greenhouse gases.

    The left over trash gets treated by anaerobic pyrrolysis to drive off volatile compounds, which can be mixed with hydrogen gas and passed over a heated catalyst to make hydrocarbons that make up even more liquid fuel.

    The residue is charcoal. This can be plowed into soils to permanently remove that carbon from the air, thereby reducing CO2 and its greenhouse effect. This is terra preta and improves soil fertility.

  4. #1204
    Quote Originally Posted by Fraggle Rocker View Post
    That's already a cottage industry. People go to McDonalds and take away their used fry-oil. McD is happy to give it to them because then they don't have to pay to have it hauled away as garbage.
    If ALL the fry oil/waste oil in the country was burned as diesel it would be roughly 1% of our oil use.

    I haven't tried it and my Mercedes mechanic insists that you can't run a diesel engine on corn or soybean oil without a little tweaking, but apparently these kids have overcome that obstacle.
    It's too thick, so it has to be heated to burn properly (and can't be used when it's really cold as it solidifies), start on diesel, use waste heat to heat the veg oil prior to injection so it can atomize it properly, switch back to diesel a few minutes before you stop the car to empty the fuel lines, so when you start it again from cold it will be diesel fuel.

    Cost of extra plumbing/heat exchanger/valves etc about a thousand or so.

    Arthur

  5. #1205
    ♫♪ Mostly Harmless ♫ ♪ F-X's Avatar
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    Quote Originally Posted by Skeptical View Post
    This is terra preta and improves soil fertility.
    It makes me happy that you know about this. The chemistry of charcoal added to soil is fascinating.

  6. #1206
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    Quote Originally Posted by adoucette View Post
    I wouldn't want to try it under all driving conditions though. Front wheel drive is here for a reason and no design has the motive power in a trailer.
    Yes, if it's snowing and you're tooling around the mountains, a pusher trailer would be an issue. But it is a solution to the issue of EV range for the case of having to take a car a long distance, and they'd be easy to rent.

    BTW pushers have been around quite a while for EV's:

    http://www.jstraubel.com/EVpusher/EVpusher2.htm
    http://www.mrsharkey.com/pusher.htm

    They're a common way to get EV's to faraway car shows and EV enthusiast meets.

    I think you underestimate how expensive this battery pack would be, so no I don't think you would just leave it around. Indeed a typical battery pack like you describe would be more expensive than a lot of cars, so no you are not going to be able to easily rent them because of the cost/liability/risk associated with that much money in a very mobile and not easily traceable platform.
    Right; I was talking about an IC engine in a trailer, not a battery. The batteries are expensive and so should stay with the car. The trailer I'm discussing would just be a small IC engine/drivetrain which won't be nearly as useful to people. Indeed, homemade pusher trailers are often just the front of a subcompact car that's been cut off. Few people will want 1/3 of a car.

  7. #1207
    Quote Originally Posted by billvon View Post
    I've often thought that a simple motorcycle-sized trailer with a small IC engine, coupled directly to the wheels of the trailer, would be a good solution to the range problem. Use the EV to get to highway speed, start the trailer engine, and let the trailer push you while you coast. If you use a little regen braking you can even recharge while you're rolling.
    That's a fine idea, but why add an extra motor when the car already has one?

    Major problems would result from a powered trailer. It doesn't have the weight to develop adequate traction and steering would be compromised.

  8. #1208
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    Quote Originally Posted by spidergoat View Post
    That's a fine idea, but why add an extra motor when the car already has one?
    Because the motor/battery the car comes with might not get you to your destination.

    Major problems would result from a powered trailer. It doesn't have the weight to develop adequate traction and steering would be compromised.
    Well, many EV enthusiasts have used pusher trailers. They're plenty heavy; they contain most of the weight of the original car and only 2 of the wheels, so those wheels are planted quite firmly. Some comments from users:

    "Despite the facts that I shortened the trailer of the Gen-2 pusher by two feet and added more IC horsepower and much more pushing force with the ability of the AT to downshift...I have still found it basically impossible to get into a condition of oversteer. (This is where the car would want to turn into the direction of the turn if you take your hand off the wheel, normaly if you release the wheel a vehicle will straighten itself out of a turn) Even in relatively tight turns with the trailer at nearly full power, the car wants to straighten itself out."

    "The trailer tracks behind the car perfectly. You can't even tell that it's there. You can't hear it and you can't feel it. The EV outweighs the trailer 3-to-1 and the hitch point is very close to the rear axle. Having 1,000 pounds of batteries in the back of the car helps a lot too, I'd guess."

    "At 40MPH on fairly straight smooth pavement, there was no discernable affect on the EV's steering or handling. In fact, it didn't feel any different from when the car is being driven by the electric motor, except for the eerie feeling of being under power while holding the clutch (on the EV) to the floor."

    "Still no anomalous handling problems to report. The car behaves just as it should, as if the pusher wasn't even there. "

  9. #1209
    It's just unnecessary when a cable could transfer the power to the car's built-in electric motor. Trailers do not generally take "most of the weight of the original car", there is a specified tongue weight. For my Ford Focus, it's only 200lbs.

  10. #1210
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    Quote Originally Posted by spidergoat View Post
    It's just unnecessary when a cable could transfer the power to the car's built-in electric motor.
    That will work as well. However, it will take significantly more fuel to generate the same power since you have the additional losses of the generator, cabling, inverter and electric motor. The trailer would have to be considerably bigger and heavier to supply the same power to the vehicle.

    Trailers do not generally take "most of the weight of the original car", there is a specified tongue weight. For my Ford Focus, it's only 200lbs.
    Pusher trailers are often built from small cars. They literally cut the front off the car and tow the front of the car behind the EV. The wheels on the trailer take all the weight of the engine, the trailer, the fuel tank etc which is most of the weight of the donor car. Traction isn't an issue. A commercial version of this would look a lot sleeker but be basically the same (an engine, differential, wheels, frame etc.)

    The tongue weight can be anything you like, determined by the center of gravity of the trailer.

  11. #1211
    My mistake about the tongue weight.

  12. #1212
    Please use Sugar Cane Alcohol Billy T's Avatar
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    Quote Originally Posted by Skeptical View Post
    ... The left over trash gets treated by (1) anaerobic pyrrolysis to drive off volatile compounds, which can be mixed with (2) hydrogen gas and passed over a (3) heated catalyst to make hydrocarbons that make up even more liquid fuel. ...
    As (1),(2) & (3) require significant energy input, I would be more impressed with this idea if you told what fraction of the output energy that input energy is. Also what is the capital cost per gallon of fuel made from trash? What is the source of the H2? - Probably natural gas.

    Thus would you not have a simpler system with greater economy to just run the car on natural gas? Just because something is possible, does not mean it is economically viable. I doubt this idea has economic viability.

  13. #1213
    Registered Senior Member
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    Is this still a thread on EVs, or what?

    See:
    http://www.sciforums.com/showthread....64#post2677264

  14. #1214
    Quote Originally Posted by billvon View Post
    Yes, if it's snowing and you're tooling around the mountains, a pusher trailer would be an issue. But it is a solution to the issue of EV range for the case of having to take a car a long distance, and they'd be easy to rent.

    BTW pushers have been around quite a while for EV's:

    http://www.jstraubel.com/EVpusher/EVpusher2.htm
    http://www.mrsharkey.com/pusher.htm

    They're a common way to get EV's to faraway car shows and EV enthusiast meets.
    They would be an issue for far more than the mountains in snow. Parking is a real problem and integrating controls of the pusher is a problem, since having the same set of controls, control both makes for a lot of changes to the primary system.

    What Enthusiasts will do doen't translate to what the public will buy nor can I see any manufacturer ever building that bride of Frankenstein combo (nor would you see me driving around in a car with a hobby servo controlling the pusher's throttle for instance, or with an exposed fuel tank sandwiched between the two vehicles).

    If you have to rent something to go a long distance it would be much easier to just rent a Car with an IC engine. And if you are going to rent to occasionally go long distances, there is a decent chance that a different car than your normal car would be a better fit for those trips, hence the currently existing and well developed rental car set of franchises, that even allow one way rentals, is a far more practical solution.

    Arthur
    Last edited by adoucette; 01-19-11 at 08:40 AM.

  15. #1215
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    Quote Originally Posted by adoucette View Post
    What Enthusiasts will do doen't translate to what the public will buy nor can I see any manufacturer ever building that bride of Frankenstein combo (nor would you see me driving around in a car with a hobby servo controlling the pusher's throttle for instance, or with an exposed fuel tank sandwiched between the two vehicles).
    People regularly buy huge trailers to tow their boats, motorcycles, PWC's etc. They often have independent braking systems and are horrendously hard to park, maneuver etc. They often have gas cans bungee corded on. And they do this not out of necessity - but for fun.

    A much smaller trailer, available for rental to get one's car across the country, or to get to the parents in an emergency, or for a once-a-year business trip? Something that you need for travel rather than just for fun? Something designed to be small, aerodynamic and safe in a crash, with extra storage room for your stuff, and available at u-haul-it? I see no reason people _wouldn't_ do that.

    If you have to rent something to go a long distance it would be much easier to just rent a Car with an IC engine.
    OK. So you want to move from LA to Florida. You have an EV as your primary car. Your options are:

    1) Rent a flatbed and have it transported across the country, then fly
    2) Sell the car, move, and buy a new car when you get there, then fly
    3) Go to U-haul-it and rent a trailer to get you there

    I have a feeling a lot of people would choose 3) as the cheaper, faster, more convenient option.

    Any solution is going to be imperfect. Current batteries cannot charge as fast as an IC car can fuel, nor do they have the range. Battery swaps have some serious problems. PHEV's work but require you to lug that engine around 24/7. This is a way to get the advantages of an EV but retain the range and rapid refueling when you need it,

  16. #1216
    Quote Originally Posted by billvon View Post
    People regularly buy huge trailers to tow their boats, motorcycles, PWC's etc. They often have independent braking systems and are horrendously hard to park, maneuver etc. They often have gas cans bungee corded on. And they do this not out of necessity - but for fun.
    Right, because it is FUN they are willing to put up with it, and they use a standard trailer hitch, so there is a universal connections, but a trailer which is pulled is not the same as a push trailer. Note that the connection is rigid in those designs. Big difference in construction, and much more complicated interface since one has to control not only the braking/lights but the throttle.

    That type of connection means the primary car has to be built with this in mind but that would add a lot of expense for the FEW people who would find this an attractive option, and that's why the big manufacturers wouldn't make it to begin with, not when there are far simpler options.

    A much smaller trailer, available for rental to get one's car across the country, or to get to the parents in an emergency, or for a once-a-year business trip? Something that you need for travel rather than just for fun? Something designed to be small, aerodynamic and safe in a crash, with extra storage room for your stuff, and available at u-haul-it? I see no reason people _wouldn't_ do that.
    Because rental places would have to keep multiple models for all the different types/makes of cars, and thus the hours of rental of each unit would be so low as to make it impractical considering how infrequently a given model would be rented.



    OK. So you want to move from LA to Florida. You have an EV as your primary car. Your options are:

    1) Rent a flatbed and have it transported across the country, then fly
    2) Sell the car, move, and buy a new car when you get there, then fly
    3) Go to U-haul-it and rent a trailer to get you there

    I have a feeling a lot of people would choose 3) as the cheaper, faster, more convenient option.
    Yes and who makes a car buying decision based on the fact that they may move across the country. No one. Oh, and when I moved from Miami to LA they shipped my Celica in the same moving van with my household goods and the extra cost was nominal.

    Any solution is going to be imperfect. Current batteries cannot charge as fast as an IC car can fuel, nor do they have the range. Battery swaps have some serious problems. PHEV's work but require you to lug that engine around 24/7. This is a way to get the advantages of an EV but retain the range and rapid refueling when you need it,
    What you are missing is the milege penalty for the weight of that engine is really pretty small while the practicality of this solution are very limited.

    The majority of people who do a lot of driving beyond the range of an EV simply won't buy one. The people who do so only occasionally will probably just rent a regular car, which is SO much easier and more practical.

    Arthur

  17. #1217
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    Quote Originally Posted by adoucette View Post
    but a trailer which is pulled is not the same as a push trailer.
    The dynamics of a pull trailer during braking are pretty much the same as the dynamics of a push trailer during acceleration.

    Note that the connection is rigid in those designs.
    No, it's not; it's a trailer hitch. If the hitch can stop a 2000 pound trailer pushing forward during braking it can deal with a push trailer pushing with a force of 500 pounds.

    Big difference in construction, and much more complicated interface since one has to control not only the braking/lights but the throttle.
    Larger boat trailers have automatic braking systems integrated into the hitch. No difference there if that's your goal.

    That type of connection means the primary car has to be built with this in mind
    Any car with a trailer hitch will work.

    Because rental places would have to keep multiple models for all the different types/makes of cars, and thus the hours of rental of each unit would be so low as to make it impractical considering how infrequently a given model would be rented.
    One type. Maybe two; you could rent one pusher-only and one that's a pusher _and_ has cargo space for hauling stuff. Compare that to the 24 types of cars that Avis rents.

    Yes and who makes a car buying decision based on the fact that they may move across the country.
    EV owners. They're used to thinking this way. Most other people aren't, and will be at a loss when they are faced with what is seemingly an insurmountable problem. Fortunately there's a solution.

    The majority of people who do a lot of driving beyond the range of an EV simply won't buy one.
    Agreed. But some will - and a lot of people will rent them if they solve their biggest problem with their EV.

  18. #1218
    It's not just brakes, you have to control the throttle as well and thus you have to have built in changes in the EV to allow that throttle to work one vs the other. Manufacturers aren't going to build that in unless there is a significant demand. Something that is not likely to occur.

    The fact is this is an extremely costly/impractical solution for which an already much simpler solution already exists.

    Simply rent a car, and then rent the kind of car you need, because the cost of renting your push trailer wouldn't be much cheaper and has many drawbacks that just renting a car does not.

    Arthur

  19. #1219
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    Quote Originally Posted by adoucette View Post
    It's not just brakes, you have to control the throttle as well
    Why? Just set the thing to maintain a 40hp output when speeds are over 20mph. Go to zero power when the brakes are applied. (Which the trailer knows about, since the brake lights and turn signals come out through a standard trailer lighting connector.) Rental companies will likely also want to set a limit of, say, 70mph, above which the trailer will reduce its power output.

    and thus you have to have built in changes in the EV to allow that throttle to work one vs the other. Manufacturers aren't going to build that in unless there is a significant demand.
    That's the beauty of such a system - you don't have to change anything. You just drive. You will just use your accelerator less.

    Simply rent a car, and then rent the kind of car you need
    That's definitely another option. It does not get your EV to where you want to go, though.

  20. #1220
    Quote Originally Posted by adoucette View Post
    It's not just brakes, you have to control the throttle as well and thus you have to have built in changes in the EV to allow that throttle to work one vs the other. Manufacturers aren't going to build that in unless there is a significant demand. Something that is not likely to occur.

    The fact is this is an extremely costly/impractical solution for which an already much simpler solution already exists.

    Simply rent a car, and then rent the kind of car you need, because the cost of renting your push trailer wouldn't be much cheaper and has many drawbacks that just renting a car does not.

    Arthur
    I could not agree with you more. It's silly. it might be more interesting to talk about GM's hydraulic hybrids.

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