Australian election

[Draco88]

How do the emissions of a gasoline-powered car compare to the extra emissions from an electrical power-generating plant which would be required to supply the electrical energy to run a car of the same size and weight, and with the same speed and acceleration?

You've asked some really interesting questions Bryan. Unfortunately i don't know the correct, or 'more to the point' answers for them all (nor do i have the time to properly investigate/research them myself), but this is an important one to take into consideration. I'll note it down so i can research it later on to know for myself.

What about the losses from the transmission of that electrical energy over very long distances from the electical power plant, to the places where the cars are recharged?

Well this i have more of an idea of. Companies these days already deal with such loss when distributing power across great distances via transmission lines. The general idea is to transmit the electricity at a very high voltage (over 100kV), since this way the current can be reduced, which is where your power loss is coming from (current=heating of conductor).

What about the "self-discharge" rates of storage batteries, where the charge will inevitably dissipate over a relatively short period of time, even when the vehicle isn't being used (gasoline doesn't evaporate anywhere _nearly_ as fast from a vehicle's fuel tank, compared to the self-discharge of storage batteries!

That's a good question too. 'Self discharge' rates varies with certain batteries I'm not sure on the specifications concerning these different batteries, however i do know that rechargeable batteries do self discharge at a higher rate than non-rechargeable, so this already introduces another limitation to electric cars based around a rechargeable battery. However keep in mind that batteries can also be better preserved at lower temperatures (i'd say below 10 degrees celcius), but this would make the whole design of an electric car a bit complicated i think.

)? Taking those things into consideration, do you have a number which compares the ultimate efficiencies of those two approaches, percentage-wise?

I don't unfortunately. I wish i did since it would be a good comparison, but you've urged me on to investigate this all myself once the semester is done with.

 

[The Gardener]

I'd think a major advantage to an electric car is that the fuel source can be flexible.

Right now, cars HAVE to run on gasoline, or ethanol. By going to a fleet of electric cars, you can power your car by coal, natural gas, nuclear, or any mix of energy sources that is most economical for the overall economy at the time.

As liquid hydrocarbon production gets tapped out and declines, its looking like we'll be increasingly relying on natural gas and coal as an energy source. I don't think putting a coal furnace in each person's car is feasible, and I'd much rather drive in a car with a solid state battery than one that will erupt like the Hindenburg if I get in an accident and the compressed natural gas tank gets punctured.

By going to a fleet of electric cars, our transportation needs can be powered by any mix of energy sources without the need to refit all of our engines.

And, yes, there is degradation of power in the transmission lines from the power plant to the place where the car is charged, but on the other hand, you get degradation in your use of gasoline while your car is running in idle while stopped at a red light, or in traffic.

 

[Bryan]

And, yes, there is degradation of power in the transmission lines from the power plant to the place where the car is charged, but on the other hand, you get degradation in your use of gasoline while your car is running in idle while stopped at a red light, or in traffic.

Yes, but that's NOTHING, compared to the self-discharge of storage batteries!

 

[The Gardener]

I didn't think about that. So, maybe this "coal gassification" really is an industry that we'll be needing in the future?

 

[somone uk]

[quote:2t4ni0hy]
What about the losses from the transmission of that electrical energy over very long distances from the electical power plant, to the places where the cars are recharged?

Well this i have more of an idea of. Companies these days already deal with such loss when distributing power across great distances via transmission lines. The general idea is to transmit the electricity at a very high voltage (over 100kV), since this way the current can be reduced, which is where your power loss is coming from (current=heating of conductor).
[/quote:2t4ni0hy]
the heating of a conductor is rougthly the power so it's p= V^2/R, or more relevantly p=I^2 * R, but that is for DC circuits, for ac it becomes more complex and I^2 * R is the "apparent power" and not he actual power

[quote:2t4ni0hy]
What about the "self-discharge" rates of storage batteries, where the charge will inevitably dissipate over a relatively short period of time, even when the vehicle isn't being used (gasoline doesn't evaporate anywhere _nearly_ as fast from a vehicle's fuel tank, compared to the self-discharge of storage batteries!

That's a good question too. 'Self discharge' rates varies with certain batteries I'm not sure on the specifications concerning these different batteries, however i do know that rechargeable batteries do self discharge at a higher rate than non-rechargeable, so this already introduces another limitation to electric cars based around a rechargeable battery. However keep in mind that batteries can also be better preserved at lower temperatures (i'd say below 10 degrees celcius), but this would make the whole design of an electric car a bit complicated i think.
[/quote:2t4ni0hy]
the self discharge or a li-ion battery is 5% / month which i don't really see a big deal about, yes it's an inefficeintcy but nothing major
though it would be a crime to use NiMh or NiCd batteries since they are ineffeiceint and self dicharge at about 25%

I didn't think about that. So, maybe this "coal gassification" really is an industry that we'll be needing in the future?

hmm i was thinking about this, if we moved to hydrogen cars we could use our old coalgas plants and add a step
CO + H2 + H2O => CO2 + 2H2
would be a fast way of filling the gap in hydrogen demand if hydrogen cars kick off
maybe you can cool the CO2 down to dry ice and then sell it in fire extinguishers
which probably would be cheaper than carbon capture and storage
maybe we should have those fire extinguishers in every home

 

[Draco88]

the heating of a conductor is rougthly the power so it's p= V^2/R, or more relevantly p=I^2 * R, but that is for DC circuits, for ac it becomes more complex and I^2 * R is the "apparent power" and not he actual power

That's it. As for AC power, well it's literally complex (not only mathematically)

 

[HughJass]

[youtube:21y8q1jh]http://www.youtube.com/watch?v=-7aapY_yMnQ[/youtube:21y8q1jh]

 

[Bryan]

the self discharge or a li-ion battery is 5% / month which i don't really see a big deal about, yes it's an inefficeintcy but nothing major

I think that's a considerable exaggeration. I use li-ion batteries in one of my flashlights, and while the self-discharge rate appears to be reasonable (at least compared to NiMH batteries, which isn't saying very much), I seriously doubt that it's anywhere near only 5%/month.

 

[somone uk]

the heating of a conductor is rougthly the power so it's p= V^2/R, or more relevantly p=I^2 * R, but that is for DC circuits, for ac it becomes more complex and I^2 * R is the "apparent power" and not he actual power

That's it. As for AC power, well it's literally complex (not only mathematically)

we try to keep it real as much as we can

[youtube:2v3k5qcc]http://www.youtube.com/watch?v=-7aapY_yMnQ[/youtube:2v3k5qcc]

i bet that guy wouldn't be popular with hitch-hikers

the self discharge or a li-ion battery is 5% / month which i don't really see a big deal about, yes it's an inefficeintcy but nothing major

I think that's a considerable exaggeration. I use li-ion batteries in one of my flashlights, and while the self-discharge rate appears to be reasonable (at least compared to NiMH batteries, which isn't saying very much), I seriously doubt that it's anywhere near only 5%/month.

i don't know it's just the figure i found when i googled it, i would probibly say personally about 10% / month

 

[Draco88]

[quote="somone uk":1vsegz7u]
the heating of a conductor is rougthly the power so it's p= V^2/R, or more relevantly p=I^2 * R, but that is for DC circuits, for ac it becomes more complex and I^2 * R is the "apparent power" and not he actual power

That's it. As for AC power, well it's literally complex (not only mathematically)

we try to keep it real as much as we can
[/quote:1vsegz7u]
haha nice one