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A problem with electric cars . . .

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Jeff7

Lifer
Jan 4, 2001
41,604
17
81
The big key to any of this is going to be more energy production, and cleaner energy production. Cars just require a means of transporting energy. I hear purely theoretical talk of antimatter reactors one day being used for power. Problem: antimatter isn't something you can just mine. It needs to be produced, and doing so is currently very inefficient. Hell, even in the Star Trek world, antimatter production is still an energy-intensive process. Antimatter, like gasoline, is just a means of storing energy for transporting something.
The big word is of course "renewables". Solar, biomass, wind, and tidal power all need to be researched and utilized more. Coal, sure we've got plenty of it here. Coal is also very dirty, and will release loads of CO2 that nature nicely stored up eons ago.
Fusion will likely be the next big thing though. Current plans call for reactors that will begin producing more power than they require to come online within the next decade. My feeling is that once fusion can go mainstream, a lot of our energy problems might finally start to go away. But that might be 50 years away before they become economically viable.
 

Zorba

Diamond Member
Oct 22, 1999
8,273
2,159
136
Originally posted by: XMan
I will say that the Tesla actually looks pretty cool. Hopefully they will sell enough that they can get the price point down so that it's more affordable.

However . . . hypothetically speaking, where's the electricity going to come from to power a large number of electric cars? We're having power issues in the summer months already; what happens when say 25% of the cars on the road are pure electrics?

From a scientific standpoint the obvious solution is to a) beef up the transmission lines, which are long overdue to be upgraded, and b) build more power plants. The big question there is, how much of a fix is there from an environmental standpoint if we're just adding more coal-burners? Not an ideal fix, obviously. So solar, hydroelectric, and nuclear are the way to go.

Solar and hydroelectric have geographic limitations. Adding a bunch of new nuke plants would thus seem to be the way to go - but aren't the same folks who clamor for less usage of fossil fuels the same ones who protest new nuke plants?

Ideally speaking we'd do away with coal burning entirely. But I don't think that can be done without nuclear power. Thoughts?
You could probably get a significant number of electric cars on the road without increasing power capacity, if you ensured that people only charged them on off peak hours.

For example: Charge your car between 7pm-6am pay $0.10/kW-h, between 6am-7pm $1.50/kW-h. Just have to have a seperate meter for the car charger.

 

BrownTown

Diamond Member
Dec 1, 2005
5,314
0
0
charging your car at night doesn't get around the fact that you are still charging it with energy produced from fossil fuels, so the greenhouse gasses are still going into the air, and of course even more are going into the air than if you burned them in your car since you are losing the energy in transmission. Electric cars make absolutely no sense if you are still using fossil fuel to create the electricity. They are only usefull if you are using something like nuclear, wind, or solar which cannot be used on in a car, but can be used on larger scales to produce energy.
 

jpeyton

Moderator in SFF, Notebooks, Pre-Built/Barebones
Moderator
Aug 23, 2003
25,387
140
116
BrownTown, it has already been discussed in this thread that even considering the dirtiest of power sources (coal, even though a lot of places in the US use other cleaner sources), pure electric cars are still cleaner to operate due to their much higher efficiency, even taking into account loss through power transmission.

As we move towards cleaner power sources in the future, pure electric vehicles will make a significant positive environmental impact.

So they still make sense now, and even more sense in the future. And I'm only talking about environmental qualities; when we talk about political and economic benefits, weening ourselves off of foriegn oil would lessen demand, increase supplies, drop prices, and have a huge positive impact on our economy.
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
0
0
Originally posted by: jpeyton
BrownTown, it has already been discussed in this thread that even considering the dirtiest of power sources (coal, even though a lot of places in the US use other cleaner sources), pure electric cars are still cleaner to operate due to their much higher efficiency, even taking into account loss through power transmission.

As we move towards cleaner power sources in the future, pure electric vehicles will make a significant positive environmental impact.

So they still make sense now, and even more sense in the future. And I'm only talking about environmental qualities; when we talk about political and economic benefits, weening ourselves off of foriegn oil would lessen demand, increase supplies, drop prices, and have a huge positive impact on our economy.
Your standard coal burning power plant used in the US gets about 40% effieciency, and yes, that is better than an internal combustion engines efficiency. However, when you add in the fact that transmission is only 90% efficient, that batteries are only 80% effiecient, and that electric motor are only 90% efficent you have lost all your advantage. It would make alot more sense to simply develop more effiecnt gas burning engines than to add new power plants, more transmission lines, and use a new type of engine + batteries in our cars. So, if you are arguing for electric cars it has to be based on the fact that we use US coal instead of Middle East oil. In terms of effiency the best you can hope for is a draw. Also, you must remember that when you add loads to the grid you are adding them at the incremental cost, not the average cost, so you are using the LEAST efficent coal and natural gas plants to produce that power, not the clean nuclear and hydroelectric. This of course does not even get into the discussion of the range and performance of electric cars which is still in question.

As someone who worked at an electic company the last 2 summer and has a decent amount of interest in electic production and distribution I actually think it would be really cool to see an expansion in this area (I actually go to power plants and 500kV substation for fun, yeah thats kinda losery I know). However, I do not think that at this time or the near future that it is economical to switch cars to electric power.
 

fitzov

Platinum Member
Jan 3, 2004
2,477
0
0
Your standard coal burning power plant used in the US gets about 40% effieciency, and yes, that is better than an internal combustion engines efficiency. However, when you add in the fact that transmission is only 90% efficient, that batteries are only 80% effiecient, and that electric motor are only 90% efficent you have lost all your advantage.
You've got a few flaws here. Generally you are ignoring the inefficiencies of producing fuel and transporting it to the car. I'd say transmission is a bit more efficient than that.
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
0
0
There are also the inefficiences of minning the coal and transporting it to the power plants. And the additional people required to run the plants etc... Also, transmission losses obviously vary, 92% might be a more accurate number, but i was trying to keep them pretty round. That electric motor might lose some efficiency when you are constantly changing the load on the motor (not an expert on DC electric motors, so not sure how differnt thigns would effect them, but usually widely varying load conditions would nto be a good ting for trying to run something at rated efficiency).

The point is that even if you are getting a few percent better (which i still doubt), you are adding considerable infrastructure that will cost alot of $$$. Wouldn't it be simpler to just adopt more efficent engines than the internal combustion engine. They already exist, jsut arent used due to industry standardization on internal combustion engines.
 

feralkid

Lifer
Jan 28, 2002
15,173
2,602
126
Originally posted by: dullard
Originally posted by: ntdz
And besides, most cars would be charging at night when people use less power anyway...
Originally posted by: BurnItDwn
Just charge the cars overnight during non peak time.
How are we going to convince 300 million people to do that?




There are 300 million automobile owners in the U.S.?

No wonder it's so congested.

:confused:
 

dullard

Elite Member
May 21, 2001
22,511
839
126
Seems like way too many people misunderstood my post. Thus, I must have written it poorly.

Here are the background details that I consider important:
[*]Electric grids are at times strained to their maximum. Brownouts, rolling blackouts, etc. are some of the results. This problem isn't located solely in California either. Even the midwest has blackouts for farm irrigation equipment on hot summer days (when ACs all over are running).
[*]Peak strain is generally in the daytime when homes, industry, businesses are all using a lot of electricity.
[*]Populaiton growth will exaggerate this problem as more and more people use electricity.
[*]Any additional strain during these peak hours will amplify those problems.

If you dispute any of those background details, please tell me which ones you dispute.

Here are the things related to electric cars:
[*]Electric cars will be an additional strain on the electric grid.
[*]Most cars will be plugged in during the evening, but a significant number will get plugged in during the daytime.
[*]Those cars which are plugged in during the daytime will further strain our electric system.

If you disagree with any of those items, please let me know which one is wrong.

My post intent:
[*]The posts above me implied the electric system would not be upgraded because there would not be a need - this is the comment I was addressing.
[*]Of the ~300 M people in the US, we'd have to convince them that IF they get an electric car, then they should not plug it in when they are done driving it (ie when it is most convenient) but instead plug it in when the electricity demand is lower.

I never said 300M people will buy electric cars. I never said that of those people who buy electric cars that all will plug them in during the day. I simply stated that some will buy the cars and of those who buy the cars, some will plug them in during peak hours. How are we going to convince those people to not plug in their car when they come home and instead to wait?
 

ScoobMaster

Platinum Member
Jan 17, 2001
2,528
10
81
Another potential problem that I don't see discussed much where electric cars are concerned:

This may not be much of a concern for those of you in southern California,
but up here in the northeast in the winter I would certainly miss all that
"waste" heat energy that combustion gasoline engines produce!

 

BrownTown

Diamond Member
Dec 1, 2005
5,314
0
0
hehe, down here in the deep south I would be jsut fine with getting rid of any additional heat :p. But yeah, the heating would have to be run off batteries instead of jsut using excess engine heat, so there you go losing some more efficiency (though I'm not sure how large a % that would be?).
 

sdifox

No Lifer
Sep 30, 2005
82,562
8,232
126
main concern for me is batery disposal and perforamce of battery in extreme weather condition. They just suck when it's cold :)
 

skyking

Lifer
Nov 21, 2001
19,217
910
136
Originally posted by: sdifox
main concern for me is batery disposal and perforamce of battery in extreme weather condition. They just suck when it's cold :)
That is a huge and often neglected cost of electric vehicles, dealing with all the hazardous waste added to the system by all those batteries. Factor that in with the 80% efficiency and it does not pencil out anymore.
For electric cars to be viable in today's economy, a source of very cheap transmission power needs to be developed, like fusion.
 

Brovane

Diamond Member
Dec 18, 2001
3,960
33
91
Peak strain is always in the daytime. Generaly between the hours of 2pm-5pm. The Power Company has excess power during the night. You cannot just turn off a Coal Power Plant our Nuclear Power Plant during the night time hours and turn it back on. These power plants never get turned off. Hyrdoelectric power plants are great for peak power because you can quickly start a hyro turbine by just letting the water flow. You then just need to setup a Time of User power meter so if a electric car owner wants to plug in there car during the day they have a strong economic incentive not to. If they do they are paying much more per kw/h than during off peak time.

Know if several 10+ million electric cars starting be added to the grid you would have strain and you have to plan capacity around that. However this can be planned for and capacity added.

Controlling emissions from power plants is much easier than controlling emissions on 100+ million vehicles.

GB
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
0
0
Umm, actually they do turn coal units on and off between the day and night. Although what you do is jsut run them at like 20% power, and then ramp them up to 100% during peak times. Nuclear is a different story, it takes days to raise the power levels to 100%, and since it is always the cheapest anyways it runs 24/7/365. So, if you did want to use elcectric cars, and charge them at night then nuclear woudl be a great way to do it since right now you only use nuclear plants for base load, but if you add car chargers at night you are considerablly raising base load without raising peak load, so you can use a larger percentage of nuclear plants. You just gotta make it so the chargers preferrenitally charge during low demand times.

So long as your cars range is larger than what you usually drive then the charger can wait till night to recharge, so its only the times when you go on long trips that you would have to recharge during the day.
 

Brovane

Diamond Member
Dec 18, 2001
3,960
33
91
My point was that they never turn off Coal Plants they are always generating some power even if at a lower power during the night. Most of the time power companies have excess power during the night. Also if you have a lot of electric cars charging at night then the power company could simply run a coal plant at say 50% output during the night.

I agree that nuclear is a great way to go for power generation. It is the only way to generate large amount of baseline electrical load cheaply with zero C20 emissions.

Most people have daily commutes of less than 60 miles round trip. There is always the people that have daily commutes of over 100+ miles however. If you use a baseline of a 60 mile range the GM EV1 meet that criteria in the 90's with its range. I have heard with modern batteries a EV1 could easily achieve a 200+ mile range. Personally for myself I would love a electric car. I commute about 25 miles a day. It would be nice to plug in my car at night and never have to visit a gas station. Also electric cars are incredibly reliable with almost no maintenance as far as the engine our power train is concerned. A electric car wouldn't work for everyone however I would love to at least have the option to purchase a decent economic electric car. It is interersted that the small amount of RAV-4 electric cars that were sold to consumers can be resold for more than the price that was originally paid for them.

GB
 

Bitek

Diamond Member
Aug 2, 2001
9,116
3,075
136
I believe the batteries were lead acid at that. Reliable but about the least energy density you can get in modern battery types.

Even NIMH batts have greatly changed since that car was out. In the hobby market, NIMH have nearly doubled in capacity 2004 to 2006. Like I said earlier, the Lithium batts that are just being developed will have even greater capacity, with ~half the weight and smaller space requirements.

the elec cars will come back eventually...
 

BrownTown

Diamond Member
Dec 1, 2005
5,314
0
0
How do these new batteries work in cold weather? The chemical reactions in batteries run slower at lower temperatures, so how much of a loss in horsepower are you gonna expect during a cold day? Its just one of many things to look into, however It shouldn't be too big a problem with some design changes. Really, the whole huge key is the batteries, the vehicles I have seen were to heavy, had to little horsepower, and too little range, and its all due to crappy batteries. If you can get batteries that are safe and cheap and can also store the reuqired energy then everything else will mroe or less fall into palce.
 

Bitek

Diamond Member
Aug 2, 2001
9,116
3,075
136
Heat is the real killer of batteries, alothough having to commercialize a product than can work from Alaska to Florida is a tech challenge. Your cell or PDA works in the winter right? I've seen some specs from the new Lithium batts that show they put out more voltage and higher capacity @ 0C than 25C.

The real prob is not overheating the batteries after constant high discharge. Even at 3-400V, car sized elect motors would still be pulling 100s of amps creating alot of heat.
As far as power is concerned, elec motors are tremendously powerful and can easily outperform gas comparable gas motors. The EV1 still did 0-60 in 7 secs, and a mild motor at that. The only problem in getting really powerful motors is you are pulling more juice, creating more heat and decreasing range. As posted earlier, I have a 1/10 scale elec RC with a "brushless" AC motor that does 0-50 in ~2-3 secs. This is the same basic tech that goes into full-size elects.

But you are right, its really the batts that are holding back the true potential of electrics, but this is changing rapidly

A123 Systems is a company that has cutting edge Lithium batt technology. Emoli is another, they make LiMn battieries (a new chemistry) and are found in Milwaukee 24V power tools now, but is also looking to expand commercially. NIMH has a lot of commercial challeges that I won't go into (like high rates of self discharge, park your car for a month and it may be about dead.)
 

newmachineoverlord

Senior member
Jan 22, 2006
484
0
0
Utilities can charge different prices for different times of day, and it is even possible to base the price of power on immediate availability, with devices sensing when the grid frequency is slow and shutting off. This is called Dynamic Demand. The key to making demand side management work is to provide lower prices to those consumers who are willing to shift demand to off peak times. The charging of electric cars is the perfect application for this. As long as demand side management is used, electric cars will mostly add to consumption of base load power, not peaking power.

The most cost effective method of adding power production to the grid is to add wind power. There are enough wind resources available on land to provide five times current human energy demands, and another seven times that available offshore. Demand side management is the killer app that could allow it to be cost effective at percentages higher than 70% of supply. Currently wind is too low a percentage of supply for the intermittency of it to be a significant issue, but ten years from now demand side management coupled with time sensitive pricing could be highly significant. If plug-in hybrid electric cars became popular with DSM pricing of electricity, electric production could shift to mostly renewables instead of mostly consumables. With net metering, you could even use an electric car as grid storage (on days you didn't plan much travel), selling power at daytime prices and buying it at night prices for profit.

edit: I fail at linking.
 

dullard

Elite Member
May 21, 2001
22,511
839
126
Originally posted by: newmachineoverlord
With net metering, you could even use an electric car as grid storage (on days you didn't plan much travel), selling power at daytime prices and buying it at night prices for profit.
I fixed your link.

 

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