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Is electric powered transpo the answer? 2

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Dinosaur

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Mar 14, 2002
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I have read many things here where folks appear to think highly of electrical transportation. I don't think much of it because the energy needed is much higher than traditional solutions. On another thread, it was reported that only 15-20% of the input energy at an electrical power plant was used at the final destination (e.g. the fuel content at the electrical plant contained 5 to 6.7 times the energy used in the home). This is because they are unable to capture all the energy in the fuel, there are productiion losses such as friction in the generators and turbines, and there are transmission losses. I do not know what the ratio is for petroleum IC engines, but I am under the impression it is much better than this. Are there any automotive engineers here that can provide some comparisons? Thanks.
 
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cranky, in cold parts of the world I'm lead to believe that you plug your car in overnight so that the battery doesn't die. I believe in some instances there's even some heating involved, perhaps of the engine block, not sure.

I guess north of the border these are available out on the street and are called 'block heater outlets'.

KENAT, probably the least qualified checker you'll ever meet...
 
I won't exchange my nice new battery for someone else's rat eaten beast. But I got solar and wind. I drove only 25 miles this week. So I need only a third of a battery.


The block heaters are 100 watts and they go in the dipstick hole to warm up the oil and block.

I came up with an old energy saving idea. I use a 10w "brown devil" resistor heated by stored photovoltaic (a pile of laptop batteries) as a hand warmer. Now I can turn down the thermostat 2 degrees. Also an electric blanket on the sofa works good.
 
The replaceable battery on a pallet idea has been kicked around for ages.

My plan - lease the battery from the supplier. Each battery is fitted with condition monitoring etc.

When you exchange a discharged battery for a charged one at a service station (drive in, robot undoes 4 bolts, takes old one away, bolts in new one, from under the car).

You are billed for (a) total usage of battery (b) net difference in state of charge (c) any damaging currents.

You get credit for returning a battery that is more highly charged than it was when you borrowed it it in the first place.

Therefore your risk is limited to having to drop into a servo again to replace a poor battery, it won't actually cost you anything. The condition monitoring should stop that happening.

Your car will be fitted with the same monitoring gear - any discrepancy will be flagged to you.

Now that is all fine and dandy. There is however a bit of a problem. What does the servo do with all these dead batteries? It needs to be alongside a powerstation.

Note that this would allow you to charge it at home, or off the engine, and keep the same battery for as long as you like.




Cheers

Greg Locock

SIG:please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
 
The battery pallet could work in some places.
There is a streach of about 200 miles East of here where the only fuel is very high priced, if you find them open.
For traveling past there you need to take care. So how would that work with batterys?
There's the issue, the vast distance in parts of the US, and probally other countries to. Then the issue of cold on the batteries, and the reduced capacity.

The other side is the heat in some places that tends to reduce battery life.

Nothings perfect, but the energy density just dosen't seem to be there in batteries.
 
Crazy idea that someone’s probably already though of # 2 –Structural Batteries

Got the idea thinking about armored ships, vehicles, Aircraft etc. Early armored craft typically had the armor as almost an after thought, added to a basic shell/frame or whatever. As such massive weight penalty with little or no structural benefit from the armor. Over time some designs started using the armor as part of the structure, leading to mass savings and/or structural improvements. (Bad news was/is that structural armor designs tended to be harder to repair if the armor was/is damaged, so it’s not universal even today I believe.)

So making the batteries structural could perhaps have the same benefit. No idea yet how you’d achieve it, or if there’s any way it’s practical but I’m throwing it out there.

As to Crazy idea #1 that someone had already thought of…

wvphysicist sorry I didn’t spend the time to address most of your concerns in my post. Next time I’ll put an entire business case.;-)

Greg, I didn't spend the time to go into details but I'd thought of most of those points. Simplistically it would be like swapping a propane tank but of course you'd want a rebate for any net charge like you said. Also some kind of damage fee. And like you say you’d still be able to recharge at home, the swap would be when you don’t have time to do so or need longer range.

As to what to do with all the dead batteries, well most of the charging could be done off peak, if the station carries a big enough stock to get it through the peak electrical hours without recharging. Not sure it would need to be next to a power station but probably near at least a sub station or however you get dedicated higher power lines.

Also to help power shaving in places like So Cal the power company would be able to stop the batteries from charging, maybe even drain some in emergencies though I'm not sure how good an idea that is. The station could also install a bunch of solar panels, or out in the boondocks wind turbine or whatever, probably wouldn't meet full demand but as a marketing tool to make all the greenies happy might work well.

So long as the mechanical and electrical interfaces are the same you could have different levels of battery, bit like the grades of fuel. Your basic lead Acid might only get you 50 miles but the lithium might get you 100, or whatever the energy densities work out at. The higher energy batteries would have a slight premium to cover the increased cost of the pack.

Gymmeh, while you probably can't make it impossible for a kid to take off you can make it difficult. You can have some kind of lock, not just the structural 'bolts', which of course might not be bolts. You can even arrange the geometry so that you need more clearance under the vehicle to remove the pack than you get in normal driving condition, I'd say your concern is one of the more easily addressed.

As to the limited range, you could still use these packs with some kind of plug in hybrid though the mass penalties might add up (unless idea # 2 is implemented ;-)).

My biggest concern would be getting ISO/ANSI/ASME/SAE or whoever to agree on the standard size/interface of the packs etc!




KENAT, probably the least qualified checker you'll ever meet...
 
If you had power lines in or under the HMA you could inductively charge the batteries while you were driving, then use the batteries off-system...
 
A couple of thoughts-

What kind of protection do you think would be needed in an accident to protect you from an exploding battery, and what does that protection do to the weight of the car?

Eventually the government will want an extra tax tacked onto your power bill for roads and such. Does that mean dedicated meters and outlets in our home just for charging or just a flat tax?

The cars we drive now are relatively heavy for what they are. My boss’s stream liner (race car) with two V8s in it is about the same weight of a Honda CRX. The auto manufacturers would need to retool with new robotic welders and it would add about $3000 to the cost of the car.

Once a viable electric solution is on the market, what do you think will happen to gas prices? Then how will these solutions look?

Just fun thoughts.
 
To paraphrase, gasoline usage won't end with a bang but a whimper. In fact, oil from coal will be around a lot longer than any of us.
 
This idea of inductively charging your car fro overhead power lines has been tried by a few hacker(for lack of a better term). The problem is sence they were stealing power they were prosecuted.
So for this to work you would need an electric meter on your car, and someone to read the meter, and someone to verify you haven't tampered with the meter, and more.
Not that it's a bad idea, it just needs a bunch more thinking, and a big coil or copper.

 
Metering won't be a problem. I don't know if you are aware of OBDII - here's an excellent dedicated reader:

It will be nothing to include charging information on a future version.

To feed all the paranoiacs out there, OBDIII will be wireless - combine that with GPS and when you drive by a cop car he'll know exactly where and when your car went somewhere (and if you deserve a speeding ticket).
 
The day they use GPS for speed monitoring is the day they get dismounted from my car and onto the wife's, or the kids bike or something. Or a fuse dropped out, a wire came loose etc.
All those guys busy unlocking phones will have a new career relabelling the GPS identifier as Paul McCatneys new car.

But, the cost of GPS for speed monitoring is next to nothing. The concept has been there since GPS became available.

Government's love investing millions on useless computer systems for ambulance management, doctors jobs, and so on and each and every time they get a cost over-run, a time over-run and the things don't actually work. They also love the idea of congenstion charging and toll roads with computer systems.

But on the off-chance they did get it to work then that government would be out of office quicker than anything.

Extreme solutions have a habit not only of not working but producing some unintended consequences.

JMW
 
Oh yes, some bloke in the UK was convicted of dangerous driving when they examined the black box in his air bags and found out his speed (at impact when the air bags deployed) was way above the limit.
Now I don't know that too many people would object to some maniac being caught by the technology, but .......

JMW
 
The ones to gain (as ever) would be the insurance companies: "Ah, I see your GPS wasn't functioning at the time of the accident. That invalidates your insurance sir."

- Steve
 
The answer then is simple, drive an old car without all the new features, or just add the ones you want.

The gas millage of older cars can be up to 30 MPG which is better than the new cars.

As far as electric cars, convert an old car for electric. t will cost much less than the newer electric cars, and it makes a nice project to work on with your son.

However, your second car probally should be a gas or diesel car for now for those longer trips.

 
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