If you're just talking about CO2 produced per mile travelled, I believe they are much better than petrol cars. But if you consider things like manufacturing and replacing and disposing batteries, it becomes less clear. Add to that the fact that in their current form, electric cars can only really be a second car unless you literally only commute in it, or have good public transport (in which case, you've probably got good public transport for commuting too anyway), and I suspect that the majority of electric car owners have a higher carbon footprint than most. Either way, the greenest form of driving is to simply keep an old car running for longer. That doesn't help manufacturing though (presumably producing spare parts isn't manufacturing) so governments aren't interested in that, and introduce ridiculous schemes where everyone scraps perfectly good cars and buys brand new ones for a tiny improvement in fuel efficiency.

Yes, it's complex.

Electric motors are far more efficient in converting energy to motion than internal combustion engines. Something like three quarters of the CO2 emissions of a gasoline powered car are just the result of burning fuel that contributed nothing to moving that car.

Electric cars are roughly 80% efficient at converting energy to motion. A gasoline car is roughly 15% efficient, a diesel can be about 20% efficient.

So, those electric cars do have a carbon footprint (per kilometer travelled) about a fifth that of their fossil fuel powered peers. That carbon is simply released at the power plant (in most cases) instead of at the car.

The source of the electricity used in electric cars has a large effect on their carbon footprint. Are the power plants nuclear? Hydroelectric? Solar?

Also, one has to consider the environmental impact of the battery systems in those cars. Batteries are not known to be particularly environmentally friendly. Lots of toxic chemistry going on there. Electric cars carry, well, a carload of the fucking things. And, they have a lifetime. After a certain number of charge-discharge cycles, they need to be replaced. I don't have any information on this subject, I haven't read much about it.

I'd suspect that if the battery system can be handled cleanly, and recycled when necessary, then overall, an electric car is going to be greener than a fossil fuel powered car. How much greener? That remains to be determined, I think.

hydrogen fuel cell, that is all

daleking wrote:Hi Everyone,

We all know about the Electric cars which tends to be an Eco-friendly car, but can anyone tell me how green is the Electric car??
I think the Electric cars that run of fossil fuel type electric power stations which means they are charged by an unclean source, like coal or oil, which may produce more pollution than an internal combustion engine vehicle and hence these cars cannot be called green. What you guys think?

True. But for people such as myself who's electricity is created through 'green' methods (in my case it's hydroelectricity) then obviously there are advantages to the environment.

Banzai! wrote:hydrogen fuel cell, that is all

Where are you planning to find all that free hydrogen? It tends to be comfortably bonded to other elements. You have to pay to get it apart, just so you can put it together with oxygen in a fuel cell. Typically, you have to pay a lot to get that free hydrogen.

all right, so the technology isn't up to the task yet, but its got to be the long term solution surely

These two links from the New Scientist website here should be interesting:
What energy is available:
Energy Realities - New Scientist
800km range car:
Lithium-Air Battery - New Scientist

Banzai! wrote:hydrogen fuel cell, that is all

A hydrogen fuel cell's just another type of battery. You put energy in to generate free hydrogen from water, and you get some of that energy back when you later re-oxidise the hydrogen.

There are also ways to run cars on things like palm oil. Problem is, you have to destroy the rainforest to build palm oil plantations.....doh.

Arcanyn wrote:

Banzai! wrote:hydrogen fuel cell, that is all

A hydrogen fuel cell's just another type of battery. You put energy in to generate free hydrogen from water, and you get some of that energy back when you later re-oxidise the hydrogen.

Are you suggesting that the fuel cell itself can be operated backwards, to generate free hydrogen?

The_Metatron wrote:

Banzai! wrote:hydrogen fuel cell, that is all

Where are you planning to find all that free hydrogen? It tends to be comfortably bonded to other elements. You have to pay to get it apart, just so you can put it together with oxygen in a fuel cell. Typically, you have to pay a lot to get that free hydrogen.

Banzai! wrote:all right, so the technology isn't up to the task yet, but its got to be the long term solution surely

Technology has little to do with it. The strength of those molecular bonds between hydrogen and other elements is the issue.

TANSTAAFL.

Renault (and I suspect other car companies have as well) has come up with an interesting approach to the electric car: essentially you buy the car and lease the battery. That way Renault can sell their electric cars at competitive prices (compared to normal cars) and you pay X amount of money per month to use the batteries. Also, this ensures that when the batteries become degraded after a certain amount of years the manufacturer can just replace them without it costing you an arm or a leg.

Also Renault developed a sort of quick-release system where you can just drive into a fuel station, swap out the batteries and resume your journey on a full charge. Essentially solving the range issue, and given that you lease the batteries it doesn't matter to you that you got another set. Of course we do need an international battery standard for this to work (imagine every brand having their own plugs and sizes, yugh).

As for efficiency, the Dutch national grid has an average efficiency of around 40%, and electric motors are around 80% or so? This would mean a total efficiency of around 30 to 35%. I don't know how efficient internal combustion engines are, but this seems quite high to me. Plus one doesn't have to use fossil fuels, one could buy 100% green energy, thus solving the CO2 emissions of electric driving.

Thus all we have left is the environmental impact of the battery construction (can we even make enough batteries?). I'm not sure how pollutant battery construction is, but I do know the prius battery pollution vs hummer story is a myth.

A diesel car does generally allow for less CO2 per kilometer / mile than a regular car, so from that viewpoint they are cleaner. I doubt you'll find any manual electric cars though, although Honda does make manual hybrids if I'm not mistaken (there's a lot of hybrids coming unto the markets nowadays).

Arcanyn wrote:

Banzai! wrote:hydrogen fuel cell, that is all

A hydrogen fuel cell's just another type of battery. You put energy in to generate free hydrogen from water, and you get some of that energy back when you later re-oxidise the hydrogen.

Yeah, but it's a type of battery that doesn't take an entire night to recharge. The advantage of hydrogen is that it's the only solution that doesn't involve significantly changing our driving habits. Of course, you could make electric cars work, but if it's not as good as what we currently have, then you're not going to convince a lot of people to switch, even if they were competitive on price. The big advantage of hydrogen is that they're already matching petrol on driving experience. With both solutions, a lot of the current problems will go away. Batteries and fuel cells will become cheaper and longer lasting. Hydrogen will be produced at a price that is affordable to most people, and the infrastructure that fuels all of this will become greener. But you are never going to get around the fact that batteries take time to charge. Even if they get it down to 10 minutes, that's still not as good as the current driver experience. Why invest in a solution that is fatally flawed from the beginning?

This website seems to be pretty good, taking the manufacturing and transportation process into account, as well as the entire fuelling process. It is shit and slow though, unfortunately. But it does seem like the diesels are holding their own against the hybrid and electric cars in their measures. VWs Bluemotion series perform well, in particular.

Of course. People can't afford to buy, run and insure a car for every purpose, so they make sure the one they can afford can do everything they need it to. And lack of luggage and passenger space are hardly the only disadvantages of a scooter. Try sitting for 9 hours in a cool, air-conditioned office after you were caught in a rain shower on the way to work. And you have to plan more with a motorbike. You can't just give someone a lift, because you need to have a second helmet. You have to think about the weather and how much you're going to carry in advance. And that's before we even begin to mention safety.