I went to a seminar and movie two Sundays ago and it's really exciting what is coming up in the world of electric cars. There are lots of misconceptions about them and some independent research is needed. One thought is that if a large number of the world's cars were electric, the extra burning of coal to generate the require electricity would cancel out any environmental benefits. My thought is: if the petrol NOT used when replaced by electric cars was used to run petrol-fired power generation, would that be cleaner and more efficient!
bigfatmat1,
May 17, 4:58am
Sounds like your seminar was a misconception If all of NZ changed to FULLY electric cars with nimh batteries it would create about a 1% increase on our electricity demands remove the infrastructure for supplying fuel pumping fuel transporting fuel extracting fuel and what and transfer than into production of batteries. Since our energy is mostly of a renewable source and places like america have incentives for renewable energy I see your statement false.
xacoon,
May 17, 5:05am
a lot of yank cities are coal fired electricity. what I reckon would be the go is diesel electric trucks, busses etc. (think trains not hybrids)
ceedoubleyou,
May 17, 5:40am
When all cars are electric, watch the price of electricity skyrocket!
ralphdog1,
May 17, 6:00am
Not convinced of the 1% bit. Say 1,000,000 cars taking 20kw/hrs a day to recharge. That is 20GWh a day, which is about 7500 GWh a year, that would be 15% + rise in consumption in NZ.
roys351,
May 17, 6:57am
hydrogen will be the way
bigfatmat1,
May 17, 2:19pm
and knock that down to 5kw hrs and the amount of times charged a week
flagheaven,
May 17, 3:39pm
ralphdog1 wrote:
Not convinced of the 1% bit. Say 1,000,000 cars taking 20kw/hrs a day to recharge. That is 20GWh a day, which is about 7500 GWh a year, that would be 15% + rise in consumption in NZ.[/quote
about 5 kw hours is it not !
thejazzpianoma,
May 17, 5:28pm
I think the point they were making was worded wrong. They probably meant we would only need 1% more generation capacity which is a different thing all together. The idea with electric cars is to have them charge at night when the grid is at very low demand. Also some forms of electrical generation are not efficiently "throttled" during low demand times, so there is a bit of a bonus in that you can be more efficient in your power generation as well.
Not unless there is some massive breakthrough with the storage or creation of it.and since we are crystal ball gazing, one could just as easily predict a massive breakthrough in battery tech for electric cars. Even if hydrogen cars become reality, most designs still rely on an internal combustion engine with all the draw backs that that has (i.e. lubrication, fueling, drive shafts/diffs/gear boxes etc) My money is on electrics :)
elect70,
May 17, 8:53pm
Expensive ,my carBMW 328does 600 + km to$!20 petrolin 7 hours ,Say itselectric&producingaverage 100 Kw power, in 7 hours its used 700 kw of electricity@ 31c a kw thats $217& thats without road taxso it sure aint going to be cheap to use & power prices are rising as fast as petrol .If you recharge it at arechargingstation then the power will cost even more !Then we will need more power stations .
sr2,
May 17, 9:13pm
Good point, but I wonder if an average figure of 100 kw is a little too high. You could probibly convert your petrol usage to BTU and factor in the engines power output efficiency for a more accurate "guesstimate". Would be interesting to see the figures.
crzyhrse,
May 17, 10:53pm
Well, you're not going to be averaging 100kW draw with normal road driving and judging by the economy figure you're claiming of 600km/$120 that's not a city figure at 9.1L/100km since you also mention 7 hours and 600km. Assuming an efficiency of a heat engine running on petrol of 30% (and that's about as good as they get) and taking the calorific value of petrol at 45MJ/kg with a bulk density of 0.95, that's using 7.8L/h to do the 600kms for $120 (55L @ $2.189/L) while using only 30% of the energy of the fuel. So that's (7.8L/h x 0.95kg/L x 45000kJ/kg) = 333MJ/h). But at 30% energy efficient that's only delivering 100MJ/h to the wheels. Which is 28kW.
Allowing for drivetrain loses, although minimal in an electric car, let's say an average 35kW, which is 46HP. At the current domestic rate of $0.23/kWH that's $8.05/h at that average power consumption. Or $56 instead of $120.
Appealing!
crzyhrse,
May 17, 10:54pm
5kWh. that's 7HP for one hour. You're not going to move a car far with that.
gs1220,
May 18, 12:40am
I saw, in a magazine article about storing hydrogen inside tiny pellets, that the cost of running an IC engine on hydrogen would be but a fraction of the cost of running it on petrol. However the hydrogen would presumably be produced using electricity so that suggests that electrical energy is a lot cheaper than the energy in petrol. Interesting if true. I've been waiting for these Indian cars powered by compressed air. All you need is a huge compressor to re-charge it. Quiet too.
welshdude,
May 18, 2:18am
I don't think the seminar is a misconception - the 'thought' was mine. I'm aware that the majority of NZ's generation is not coal but that it is more common in other countries. I still wonder - is it more efficient to burn fossil fuels in power stations then distribute that energy to power electric cars than it is to have individual engines in cars burning fossil fuels!
Woops, sorry about that folks. I think I just set a TM MB record for posting the worlds longest link, and it works!
Since the public registrations are closed, you must have an invite from a current member to be able to register and post in this thread.
Have an account? Login here.