Electric cars are a pipe dream

So..... why don't we just give all the EV's a battery as large as the Tesla's battery? Is there some fundamental law that says EV's must have small batteries?

I guess not. Well, the bulkiness of the car might bring down the airresistance ratio. And it adds weight, but yes they could put bigger batteries in smaller cars too.

My bet is that, if the Tesla has a successful enough run, we'll start seeing cheaper cars that are exactly identical to it in about 10 years.

I agree with everything you said and yes, 10 years seems to be doable. Which brings it to my original point, that not RIGHT now...

EVs are like Linux, every year is going to be theirs. :)
 
Look at power-to-weight-ratios for top speed: land vehicles require less power for a given speed/ size.

You don't mind solving this for me?

"Students will be given the following math question:
One boat can carry cargo equivalent to 5-6 trains, or 500-600 train cars. Each train car
holds the equivalent to 3 semi truckloads. 1800 semis = 1 boat. Boats get 45-50 gallons per
mile.
1. Determine the miles per gallon of a ship.
2. If a truck could get 10 mpg, how does the gas mileage compare between semis and
ships?
3. Which is more economically feasible?"

---------------------------------------

Furthermore:

Transportation Modes: An Overview

Maritime transportation (Concept 4). Because of the physical properties of water conferring buoyancy and limited friction, maritime transportation is the most effective mode to move large quantities of cargo over long distances.

http://people.hofstra.edu/geotrans/eng/ch3en/conc3en/ch3c1en.html

Are we good now?
 
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You don't mind solving this for me?
"Students will be given the following math question:
One boat can carry cargo equivalent to 5-6 trains, or 500-600 train cars. Each train car holds the equivalent to 3 semi truckloads. 1800 semis = 1 boat. Boats get 45-50 gallons per mile.
1. Determine the miles per gallon of a ship.
2. If a truck could get 10 mpg, how does the gas mileage compare between semis and ships?
3. Which is more economically feasible?"
At what speed?
Bearing in mind your call for 70 mph...
At what fuel consumption?
How often do we pack that many people into one vehicle on land?
Specious question.
How about: why can we get 70 mph from a moped of 50 cc engine capacity yet for a water-borne vehicle (jet ski) to approach that speed it requires 400+ cc?
How about a sport jetski that requires a 1500 cc 255 HP engine and does ~ 70 mph yet a Suzuki GSX-R 1000 with 160 HP will do ~200 mph?

Do try to keep your contentions straight: you first claimed that water travel requires less energy and now you're comparing slow-speed efficiency.
Apples and oranges.
 
John99 said:
Dywyddyr, what do you think of post 49 and using the rotation of the drive shaft or rims?
This bit?
John99 said:
Kinetic energy, utilizing the length of the drive shaft or rims is supplemental power, but this needs to be stored, obviously since the car is not always moving.
Nice idea but taking power off the rotating components causes friction and would slow down the shaft/ wheels, and the whole point is get them rotating as efficiently as possible.
Regenerative power recovery may well cost more than it's worth in losses and increased heating, not mention the extra weight of equipment required to convert that rotation into energy and then store it.
 
Seriously dude, you are offtopic and incorrect. I thought it was common sense and public knowledge that water transportation was the most cost effective...

Apples and oranges.

Exactly. That's why it was stupid for Quadro to bring up submarines... :)

Now if you can't focus on the topic, I will be just ignoring you as I do with Quadro...
 
Seriously dude, you are offtopic and incorrect. I thought it was common sense and public knowledge that water transportation was the most cost effective...
Changing the goal posts again.
Is that because you can't refute the point that water transport requires more power than land transport?
You originally claimed it used less energy.

Now if you can't focus on the topic, I will be just ignoring you as I do with Quadro...
Go ahead, but as long you make stupid comments I'll correct them.
 
I will give you one last chance with a homework:
You have 10000 T of cargo to be transported from NYC to Miami. You can use ship, truck or plane. Which is the cheapest way?
Let me help you: http://en.wikipedia.org/wiki/Fuel_efficiency_in_transportation

Funny you should give that link:
Concorde the supersonic transport managed about 17 miles to the gallon per passenger
Cunard state that their liner, the RMS Queen Elizabeth 2, travels 49.5 feet per imperial gallon of diesel oil (3.32 m/L or 41.2 ft/US gal), and that it has a passenger capacity of 1777.[26] Thus carrying 1777 passengers we can calculate an efficiency of 16.7 passenger-miles per imperial gallon
So Concorde and the QE2 are both ~ 17 passenger miles per gallon.
A trial of a Colorado Railcar double-deck DMU hauling two Bombardier Bi-level coaches found fuel consumption to be 128 US gallons (480 l; 107 imp gal) for 144 miles (232 km), or 1.125 mpg-US (209.1 L/100 km; 1.351 mpg-imp). The DMU has 92 seats, the coaches typically have 162 seats, for a total of 416 seats. With all seats filled the efficiency would be 468 passenger-miles per US gallon
So train is ~28 times better.
A diesel bus commuter service in Santa Barbara, CA, USA found average diesel bus efficiency of 6.0 mpg-US (39 L/100 km; 7.2 mpg-imp) (using MCI 102DL3 buses). With all 55 seats filled this equates to 330 passenger-mpg, with 70% filled the efficiency would be 231 passenger-mpg
And a bus is ~ 14 times better.

Now tell me again about
Traveling in/on water takes fucking way LESS energy than traveling on dry land.
 
Just to make you happy and get back on track, I will buy a personal electric train when they are on sale for my transportation.
Can you make the same math for CARGO instead of per person? I thought in your homework the cargo was 10000 T not passengers...

Damn, I can put moderators on Ignore, what a pity!
 
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Now let me tell you about transporting/traveling on water compared to dry land:

http://people.hofstra.edu/geotrans/eng/ch8en/conc8en/ch8c2en.html

"Freight transportation is dominated by rail and shipping, the two most energy efficient modes. Coastal and inland waterways provide an energy efficient method of transporting passengers and cargoes. A tow boat moving a typical 15-barges tow holds the equivalent of 225 rail car loads or 870 truck loads. The grounds for favoring coastal and inland navigation are also based on lower energy consumption rates of shipping and the general overall smaller externalities of water transportation. The United States Marine Transportation System National Advisory Council has measured the distance that one ton of cargo can be moved with 3.785 liters of fuel. A tow boat operating on the inland waterways can move one ton of barge cargo 857 kilometers. The same amount of fuel will move one ton of rail cargo 337 kilometers or one ton of highway cargo 98 kilometers."

Are we really good now? A boat is 120% more efficient/economical than train and 8.5 times than trucks....

So my statement that water transportation is way more efficient and economical than on dry land still stands as correct... :)

P.S.: Further obvious, irrelevant and offtopic discussions of water and train transportations will be ignored.
 
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I see you didn't look at the chart at the bottom of the page on the link you posted...
Well done.
 
Then you don't mind if I will just ignore your input from now on.

You promise?

Alternatively, you could just stop debating like an insecure high school underclassman, and you wouldn't be subjected to inputs that cause such dissonance in you.
 
Water provides more friction then air+rails, no doubt about it, plus a propeller is not as efficient as a drive shaft to a wheel. airplanes loose efficiency despite the lack of ground friction because so much energy is "wasted" keeping the plane in the air, a 250 ton 747 must move the equivalent of 250 tons of straight air down in order to fly ever second.
 
syg said:
Now what about all those professional cars driven in city traffic all day? Taxi, delivery,etc?
Electric power is ideal for most of them - low mileage, lots of idle time, starting and stopping frequently - that's where the regenerative braking and lack of power consumption while stopped are most advantageous.

syg said:
Kilo_class_submarine is pretty heavy at 3000 tons submerged, with a 400 mile range on battery power.

With the incredible speed of:

Endurance
400 nautical miles (700 km) at 3 knots (6 km/h) submerged

Not to mention it is way easier to move weight in water than on dry land, so try again...
You seemed to be under the misapprehension that battery power was incapable of powering heavy vehicles. That was a significant counterexample. The battery powered switch engines in your local rail yard provide another.

Water resistance is much greater, and increases much more rapidly with speed, than rolling and air resistance, so the speed comparison is irrelevant. The 400k range would be much longer, not shorter, on dry land.
syg said:
2. Fast acceleration kills the battery faster. It is not desired...
3. Super top speed is not desired either.
The argument was that performance suffered from switching to electric power. The Tesla counters that.
syg said:
Are we really good now? A boat is 120% more efficient/economical than train and 8.5 times than trucks....

So my statement that water transportation is way more efficient and economical than on dry land still stands as correct..
You are now ignoring the factor you found most important in the initial post on this issue - the speed.

Trucks allowed to travel 10 mph steadily without starting and stopping and idling would be quite a bit more efficient than current trucking - quite possibly getting into ship territory or even better. A train would certainly be far more efficient than a ship, under such parameters of operation.

The point is that anything capable of moving 3000 tons 400k through water is more than capable of handling ordinary weight or size of cargo on land.
 
Re water versus land transport.

I support syzygys here.

It is not a simple equation. Resistance to movement through water varies enormously depending on various factors. However, a large ship travelling at or below displacement speed will expend less energy per tonne kilometre for its cargo than any land vehicle.

If the vessel is a small planing boat, such as a jet ski, the equations are very different.

Strangely, the most efficient in terms of energy per tonne kilometre is a submarine. This is because the drag at the air/water interface for a floating vessel is greater than the drag of a fully submerged vessel. Some submarines are capable of amazing feats, though finding out exactly what is almost impossible, since these are military secrets. Certainly military submarines are capable of more than 70 knots, while expending relatively little energy for their size and speed.
 
People, keep focus and stop the stupidity specially if it was already answered:

Electric power is ideal for most of them - low mileage,

For a taxi? The average NYC cab traveled 141 miles per shift in 1990:

http://www.schallerconsult.com/taxi/taxifb.pdf

So today's EVs wouldn't make through one shift, since that miles increased since 1990..

You seemed to be under the misapprehension that battery power was incapable of powering heavy vehicles. That was a significant counterexample.

My hairy ass. On dry land. Haven't I just proved that it is way more energy efficient to move heavy shit in water, thus it is easier to do so for batteries too??? Bringing up submarines is stupid...

Where is my electric truck when I need it? oh wait, there is no such a thing...

The point is that anything capable of moving 3000 tons 400k through water is more than capable of handling ordinary weight or size of cargo on land.

So where is my electric TRUCK??? Did you steal it??? :)
 
Re water versus land transport.

I support syzygys here.

Well, thanks but I think simple logic, facts and knowing 6th grade physics should be fine for my support. :)

Anyhow, I kind of moved on so unless we can get back to electric cars (for by the way I provided better support than the advocates), I am not interested in passenger average, speed factors and such...

The real question is how low the Li-ion battery's price can come down, before another oil company buys the patent rights... :eek:

With the NiMH batteries there hasn't been any improvement in the last 8 years....(and they were actually quite decent back then)
 
Hey, I did find an electric truck! It isn't an 18 wheeler and has several limitations (price 3 times of diesel truck, 100 miles range,speed) but it is a truck:

http://blogs.forbes.com/energysource/2010/05/13/special-delivery-via-electric-truck/

And also proves my point of batteries not carrying heavy shit on dry land for very far....

"Navistar's new electric truck, called eStar, which is being unveiled today. When Navistar surveyed customers like utilities and package and snack delivery companies it found that 82% had daily routes less than 100 miles. Enter eStar, which can go 100 miles on a charge. Its battery is an 80 kilowatt-hour lithium ion battery made by A123 Systems that powers a 70-kilowatt motor (that translates to a pretty puny 93 horsepower). A full recharge takes eight hours. Top speed: 50 mph.

The thing isn't cheap, at least for now. It will cost $150,000, compared with $50,000 or so for a similar sized truck. "
 
The real question is how low the Li-ion battery's price can come down, before another oil company buys the patent rights...

With the NiMH batteries there hasn't been any improvement in the last 8 years....(and they were actually quite decent back then)


Really, if oil companies are buying up the rights, it can only be motivated by some kind of collusion. Otherwise, why would any one oil company bear the full financial brunt alone for keeping a tech off the market, when all the oil companies stand to lose together? At the very least, it's a predatory business tactic. But, nobody in the government is going to take action unless the public is sufficiently outraged to force their hand.

So, the problem starts and ends with public support.

I agree with everything you said and yes, 10 years seems to be doable. Which brings it to my original point, that not RIGHT now...

True, but the Tesla has to have a successful run, or the 10 year thing will never happen.

EVs are like Linux, every year is going to be theirs. :)

Lol. I think that got thirty straight seconds of laughter out of me. Poor Linux. :( Poor EV's. :(
 
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