Electric Cars Use More Oil and Coal and Produce More Emissions

reply to post by CB328


I wish everyone that wants to comment would learn some math, physics and engineering and not just believe everything from a propaganda website with an agenda. Jesus think a little bit, just don't drink the kool-ade!

reply to post by billyjack

Yes, the site blatantly lied. California uses about 25% coal power. Big black clouds come out of those electric cars hundreds of miles inland.

Yet another "electric cars are not as green as gas" thread!

Let's put this in perspective:

In any complex system there are losses, the same goes for transmitting and using electricity. I don't know the exact figure but let's assume that the 7% transmission loss stated in this thread is correct.

The charger for a modern electric car is not the simple, inefficient device you have for your AA batteries. Losing a few Watts there is not worth bothering about as you save much more by not having to buy throw-away cells.

A well designed high power charger should be better than 90% efficient, it is possible to get up to 98% efficiency with current devices. The internal losses are really very small.

The losses in the battery may well be 90%, and the motor/inverter system may also be only (ONLY!!!) 90% efficient. But that still gives a Power Plant to Wheel efficiency of some 67% (multiply them together and include the transmission loss).

I think that you'll find that a modern power plant is in the region of 40 - 60% efficient, which drops the fuel to wheel efficiency to only 33% (sorry I don't have the numbers handy as I'm on vacation - but I thought I'd put my comments in anyway. Anybody with real numbers please correct me on this.

Compare that with the efficiency of a petrol or diesel car. You'll be lucky to hit 15% for petrol and 20% for diesel. And that is with the engine running at optimum revs.

That's why a gas car needs a gearbox. You have to try to match the speed of the car with the most efficient speed of the engine. At all other engine speeds you are running at less than optimum efficiency.

Reciprocating engines are horrendously inefficient! So Power Stations use the more efficient turbines to provide rotary motion. And these turbines are designed to run at their optimum speed (maximum efficiency) all the time.

Producing Megawatts of power in one place means that it is much easier to scrub any resulting pollutants from the Power Station "exhaust" as well. Everything can be optimised as you don't have a tiny mobile system to cope with.

Yes, cars have to be manufactured and that causes pollution as well. But an electric car, by its very nature, has far fewer parts in its construction. The body panels will be very similar to those in an ICE car but the frame and support structure can be much simpler with fewer things to "bolt on". Look at the "skateboard" chassis of Tesla's Model S, designed from the ground up as a pure electric car.

The batteries certainly contain some nasty materials but these are almost 100% recyclable at the end of the battery's life. They don't leave a trail of pollutants behind them like a gas car!

So much for at least some of the "hidden environmental costs" of electric cars. What about the "hidden environmental costs" of oil?

It is very dishonest to talk about the pollution produced from a gas car by considering only the exhaust system. If you want to do a "Well to Wheel" comparison then think about the hidden costs of oil.

It has to be mined (drilled), transported, refined and stored. Yes, these things apply to an oil powered power station and, in a similar way, to a coal powered station. But electricity can be produced in many ways, and as the nation moves to more sustainable means of power production SO DOES THE ELECTRIC CAR! You can't say that for the gas car.

Every nation has its own way to subsidise gas. If they didn't you would be paying many times the current pump price. But things like armies in certain countries (to protect our interests, i.e. oil) and the occasional unfortunate oil spill (shame about the wildlife), not to mention the loss and destruction of wildlife habitat are absorbed by other fundings or simply ignored.

Toyota estimated that it takes about 7.5kW of electricity to refine one gallon of petrol. Interesting - that same 7.5kW could take most electric cars 20 miles or more! Without any petrol!

Even if you look at the most pessimistic figures it's still far more efficient and environmentally friendly to produce power (electricity) in a small number of relatively efficient large power stations than in millions of tiny very inefficient ones.

Then think of the "hidden cost" of health care that YOU pay for if you suffer from a health problem caused by those small power plants (gas cars) driving past you every day!

And don't get me talking about the even worse fracking that Big Oil wants to use to get us tied to the Hydrogen pump! That's for another thread.

I have an idea.
Why not have the electric cars carry their own generator like a diesel/electric locomotive.
These machines produce massive torque. What is the cost per ton mile moving a whole train?
An automobile with a small gasoline or diesel engine powering a generator to drive electric motors at the wheels should be fairly efficient, don't you think? It can also take less space and be lighter than a bunch of environmentally messy batteries.

reply to post by Beartracker16


Great idea but it has problems. What you're describing is a "series hybrid" car and both the Toyota Prius and the Chevvy Volt can work in this mode. It works best if you have a really efficient gas engine and that means a micro turbine. But as far as I know there is no production car using this system. Some of the high end manufacturers have tried it with "concept cars" but we know that they never come to market!

So the best compromise at the moment is to use an ICE as the power for the generator and allow some sort of mechanical system to allow either all electric or mixed drive to the wheels. Essentially you use an additional asymmetrical differential gear to combine the drives from the gas engine and the electric motor. The same gear can allow all electric drive, and in this mode the car is operating as a series hybrid just as you describe.

And here's the problem: you have to shoehorn an electric drive and a gas drive into one car so everything is compromised! You still need batteries to act as an "energy buffer" in any system so that the motor/generator is able to work at its best efficiency, and the batteries can be quite small as in the Prius or bigger as in the Volt, but it's still a complicated compromise.

In a diesel-electric locomotive you've got plenty of space to get everything optimised but it's not so easy in a car. You end up with a more efficient gas car than running with only a gas engine but you compromise performance in one way or another. It can be a very good car but it's neither a great electric car or a great gas car!

a reply to: JohnBingham
All very valid points. Thank you for your input. We are still so slow at converting our oil into solar panels, hope the last longer.

a reply to: faryjay

That's all well and good! But they aren't creating extra electricity for these cars,

Not so sure about that. If electric cars are a new consumer of electric energy than the electric energy supplier will need to increase its production to meet the new demand. '

Also, with fuel prices where they are, I'd rather take an electric car any day!

I have seen reports several years back that most people will not get back the upfront cost they put into the green vehicle by gas savings.

Hello,

I don't have much to add to this thread, as a lot of people have already said what needs to be said... But let me generalize a few things about energy, if you don't mind.
In general, the more steps you put into energy production, the less efficient the system can be. For a coal power plant, you need to burn the fuel, generally heat water into steam, and use that to turn a turbine to generate electricity. So, you lose energy heating water and to friction/resistance in moving the turbine. You also lose energy in transport via cables, and because we need to transport this energy over long distances, the current must be converted from DC to AC... And finally, it is common for this energy to go through a transformer so that the voltage is safely and efficiently changed before being used... A lot of these systems have been optimized for efficiency, but that doesn't make them efficient.
You could argue the same thing for a gasoline powered engine (it takes energy to refine crude to get gasoline and... ). What you cannot argue with is energy density and practical storage. Gasoline has a decent energy density and can be stored relatively safely (compared to gases). Electricity storage isn't great, but it's alright too.
Every single method of energy production has downsides, inefficiencies, and impractical uses. EVERY SINGLE ONE.

Cheers.

a reply to: liejunkie01
Save up 2 thousand dollars every few years to replace the batteries.