What effect do you think electric cars will have on electricity costs?

Amethyst

Give me a museum and I'll fill it. (Picasso) Give me a forum ...
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Being on the "green" end of the political spectrum, I'm excited about the potential of electric cars; I'm also cheap, and the hype about electric cars is they only cost $.02 per mile to run.

Given that electricity is generated, in most cases, by burning fossil fuel, and the cost of electricity is going higher and higher, could electric cars end up costing more to run than gasoline-powered ones?

That wouldn't necessarily put me off electric cars, given their advantages; I just want to be aware of facts, not blinded by hype.

(Notice I said "potential" of electric cars....their mileage range before re-charging does not yet meet our key performance parameter).
 
I've always liked the idea that you could buy the car (and maybe buy the home solar collector array to charge it up) and the capital cost was almost all you had to buy. I think these have strong appeal to go together. Fully rechargeable electric car that mostly only runs on batteries. No additional gasoline (or charging) cost unless you go on a long range trip. Batteries and solar panels are both not ready yet, though it's been many many years of development.

If we ever get there, I wonder about the long term effect of taking that much solar heat and converting it to electricity. Would it be large enough effect to be measurable? If so, is it good for global warming?
 
What effect do you think electric cars will have on electricity costs?


In the foreseeable future, none. There are very few plug in eletric cars. The ones that exist are experimental for the most part, put no apprecible additional load on the grid.

When, in the next 5 to 10 years enough advance is made in battery technology for commercial automotive propulsion use, most of them will be recharged at night, when the grid demand is lower. Likely to have minimal impact until 10 to 15 years out.

At some point if the battery technology gets really good (yeah right) there may be a critical mass off them to make difference. By then I'm sure most of us will be in the "transported" mode, not nececessarily caring, or be cognizant of what propulsion system is employed
 
I think if there's ever a critical mass of them, we'd see more of a push to time-of-day pricing of electricity to encourage the recharging of batteries overnight. The main reason is that there tends to be spare generating capacity overnight, whereas extensive daytime recharging could require building more power plants, which is expensive and subject to NIMBYism.
 
(snip)
If we ever get there, I wonder about the long term effect of taking that much solar heat and converting it to electricity. Would it be large enough effect to be measurable? If so, is it good for global warming?
I do not think photovoltaic panels convert solar heat to electricity. If I understand correctly what I've read about them, they directly convert the light energy of incoming photons into electrical energy. I suppose large areas of solar panels, which are dark in coloring, could have some local heating effect, but I have no idea what the magnitude of such an effect might be, if it exists at all.
 
Given that electricity is generated, in most cases, by burning fossil fuel, and the cost of electricity is going higher and higher, could electric cars end up costing more to run than gasoline-powered ones?

That depends on your electric company.

Electric engines are much, much, more efficient than internal combustion engines.
 
Electric engines are much, much, more efficient than internal combustion engines.

This may be true, but the overall production of electricity to charge the batteries to run the cars is still nearly as inefficient as the internal combustion engine itself. IIRC, electric power production is the second most inefficient use (next to transportation) of raw energy, and it's a fairly close second.
 
Right now natural gas, propane, and electric are less expensive to operate than the traditional gasoline or diesel auto. However, there is probably a move in every state to change over to a tax system based not only on fuel but also on use. New cars will be required to have use indicators that transmit use directly at the time of fueling or yearly inspection.

There are numerous "NEW TAX METHODS" in the works. Right now we pay a sewer charge based on our water consumption. These revenues are short of covering expenses for both the water and sewage systems. So in the works is a tax based on property runoff. By using Google Earth technology, the square ft of your property will be computer analyzed for roof surface, driveway surface and other none water using areas to calculate a "WATER RUNOFF TAX".

Anything goes to keep the public system a float with money for pork...
while the private sector disappears.
 
electric power production is the second most inefficient use (next to transportation) of raw energy, and it's a fairly close second

Yes, this is the concern that I had in mind.

the square ft of your property will be computer analyzed for roof surface, driveway surface and other none water using areas to calculate a "WATER RUNOFF TAX".

Oh, terrific, now I have one more thing to worry about (we have 3.5 acres and are on a well/septic tank). :p
 
This may be true, but the overall production of electricity to charge the batteries to run the cars is still nearly as inefficient as the internal combustion engine itself. IIRC, electric power production is the second most inefficient use (next to transportation) of raw energy, and it's a fairly close second.

There's a reason why it costs $.02/mile to run an electric vehicle.

"Nearly as inefficient," for fossil plants, is >10% more efficient than a well-tuned IC engine (30-to-33). The overall efficiency of US power plants is even higher since we have a healthy percentage of nuclear and hydro.

The numbers are out there. Do the math yourself.


Edit: The EPA has the average efficiency of fossil plants at 33%. I've changed that above.
 
The numbers are out there. Do the math yourself.

Oh very well, harrumph. :LOL: :rolleyes:
 
When, in the next 5 to 10 years enough advance is made in battery technology for commercial automotive propulsion use, most of them will be recharged at night, when the grid demand is lower. Likely to have minimal impact until 10 to 15 years out.
The Navy's submarine force has been using industrial-strength batteries for over a century. Even with a nuclear reactor providing power & light, when it scrams the battery picks up the load until something else can take over.

You'd think that a century of military-industrial research would generate rapid advances in battery technology. Today's average battery on a LOS ANGELES-class submarine is over 125 foot-square four-foot high cells of lead-acid plates & electrolyte. The lead plates are the thinnest & stiffest possible, with humongous electric surface area, and the electrolyte is tweaked for high performance with its own agitation system. But at the battery's core it's not much more sophisticated than the technology available to my great-grandfather. In fact my grandfather could probably have hopped down into the well and figured things out in about five minutes. And after five or ten years of hard use, you have to start jumpering out a few of the cells to eliminate the weakest links. Great battery with lots of capacity and a high-discharge rating, but it's only incremental improvements to technology that's been pushed as far as it can go.

I'm not holding my breath for NiMH or LiIon advances.
 
"Nearly as inefficient," for fossil plants, is >10% more efficient than a well-tuned IC engine (30-to-33). The overall efficiency of US power plants is even higher since we have a healthy percentage of nuclear and hydro.

The numbers are out there. Do the math yourself.

Are you objecting to my using the phrase "nearly as inefficient"?

Using your numbers:

FF electric power production => 67% inefficient

well-tune IC engine => 70% inefficient

Actually, I'm not sure that nuclear raises the thermal efficiency of a power plant, since I believe a nuclear-fired boiler discharges waste heat at a higher temperature than a FF-fired boiler. But I see Nords is here now, and I'm sure he will correct me if I'm wrong about nuclear thermal efficiency.
 
Actually, I'm not sure that nuclear raises the thermal efficiency of a power plant, since I believe a nuclear-fired boiler discharges waste heat at a higher temperature than a FF-fired boiler. But I see Nords is here now, and I'm sure he will correct me if I'm wrong about nuclear thermal efficiency.
Going back about 26 years to nuclear power school, the thermal efficiency of a typical naval pressurized-water reactor is... (drum roll)... about 17%.

The steam generators make saturated, not superheated, and a lotta heat is thrown away in those condensers. Gumby may have better data on civilian reactors.

My 15-year-old photovoltaic panels have a conversion efficiency of about 10%, newer panels are pushing 14%, and the latest thin-film models coming out of the laboratory (not quite yet ready for prime time) are rumored to be over 18%.
 
Are you objecting to my using the phrase "nearly as inefficient"?

Using your numbers:

FF electric power production => 67% inefficient

well-tune IC engine => 70% inefficient

I'm going to make another correction. I found the lower EPA number for fossil fuel plants last time. This time, I've found the lower number for a car IC engine. A car IC engine is only about 20% efficient. There are more efficient IC engines (like in a factory) but the passenger car doesn't have one.

Advanced Technologies & Energy Efficiency

That's an even larger improvement of coal burning power plants over a typical car IC engine.

Older civilian reactors, which is what we have in the states, are 33% efficient. Same improvement as a coal burning plant. Of course, reactors don't use fossil fuels in normal operation, which is what we're really after and why we care about electric cars.

Lower CO2 emissions and lower per mileage costs. What's not to like? Well, if the battery problem gets sorted.

If you don't believe me - and I know you won't - do the math yourself. I'll get you started.

1hp = 746 watts
 
Ok, from your new numbers

IC engine = 20% efficient

FF power plant = 33% efficient

Chemical energy in battery to wheels = 75% efficient => from your link

Battery charging efficiency = ~ 80% (not sure of this number, but I think it's probably close)

Total efficiency of electric car = 33% x 80% x 75% = 20% => Hmm, about the same overall efficiency as the IC engine :confused:
 
You'd think that a century of military-industrial research would generate rapid advances in battery technology. Today's average battery on a LOS ANGELES-class submarine is over 125 foot-square four-foot high cells of lead-acid plates & electrolyte. .

I think that part (but not necessarily all) of the reason is that weight doesn't matter much for submarines.

The specific energy of Li-ion has increased from 100 Wh/kg to 200 Wh/kg since it was invented in the early 90s. Not exactly Moore's Law but still pretty good. Lead-acid is only about 40 Wh/kg. But cost and safety are still concerns for large Li-ion batteries.
 
My 15-year-old photovoltaic panels have a conversion efficiency of about 10%, newer panels are pushing 14%, and the latest thin-film models coming out of the laboratory (not quite yet ready for prime time) are rumored to be over 18%.

From: High Efficiency Solar Arrays

"In 1999, Spectrolab announced the completion of multi-junction solar cells, which will achieve a conversion rate of nearly 27 percent."

But I doubt they will fit into your ER budget ;)
 
Ok, from your new numbers

IC engine = 20% efficient

FF power plant = 33% efficient

Chemical energy in battery to wheels = 75% efficient => from your link

Battery charging efficiency = ~ 80% (not sure of this number, but I think it's probably close)

Total efficiency of electric car = 33% x 80% x 75% = 20% => Hmm, about the same overall efficiency as the IC engine :confused:

Lithium Ion batteries have a 99% charge efficiency. Even sealed acid batteries have >90% or more charge efficiency. An 80% ce battery would be one of those old lead acid batteries that required water every month.
 
Ok, from your new numbers

IC engine = 20% efficient

FF power plant = 33% efficient

Chemical energy in battery to wheels = 75% efficient => from your link

Battery charging efficiency = ~ 80% (not sure of this number, but I think it's probably close)

Total efficiency of electric car = 33% x 80% x 75% = 20% => Hmm, about the same overall efficiency as the IC engine :confused:

How did the electricity get from the power plant to the electric car? Several hundred miles of wire, several transformers. Every step of the way there are losses. Our present grid is approximately 90.5% efficient. "Plug" (har, har) that into your equation for electric cars and they become less efficient than IC cars.

OTOH, the IC engine efficiency doesn't include the fuel burned in physically transporting the fuel from the refinery to the gas station.

Overall, it looks like a plug-in car will use about the same amount of energy as an IC car. Whether it is "greener" or not depends on where the energy is coming from--and how far it travels to get to your socket.

Being on the "green" end of the political spectrum . . .
Is being environmentally conscious a political attribute? I hope not. If it is, we should never discuss it on this forum--it would be verboten, as it might get someone upset or something.
 
To muck things up even more.

Cradle to grave efficiencies are harder to figure out.

Throw in transportation costs of coal, gas, oil, ore, mining, refining and concentrating of reactor fuel, disposal of fly ash, spent reactor fuel, co2 emissions, carbon credits, ---I'm running out of breath---, environmental impact studies, government permits, political kickbacks, security costs, river heating from cooling stacks, fish population studies, snail darter, a few wars to keep it going or keeping it form others, etc..

Whew, no end in sight for collateral expenses. All of which impacts total efficiency.

Go figure.:flowers:
 
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Is being environmentally conscious a political attribute? I hope not. If it is, we should never discuss it on this forum--it would be verboten, as it might get someone upset or something

Eeek sorry, I should not have phrased it that way. And won't do it again :-X

The discussion has not been quite what I expected, but fascinating all the same.
 
How did the electricity get from the power plant to the electric car? Several hundred miles of wire, several transformers. Every step of the way there are losses. Our present grid is approximately 90.5% efficient. "Plug" (har, har) that into your equation for electric cars and they become less efficient than IC cars.

OTOH, the IC engine efficiency doesn't include the fuel burned in physically transporting the fuel from the refinery to the gas station.

And the efficiency of an electric motor doesn't include the efficiency of production and transportation of electricity.
You can't get an accurate comparison of efficiencies if you compare 'well to wheel' efficiency of one to the 'engine to wheel' efficiency of the other.

In addition, why take the worse case of fossil fuel efficiencies? My energy comes from solar, wind, nuclear, natural gas and some coal. Coal overall is half of our electric power generation. Most of the other half is more efficient.
 
I'll have to find some better sources, don't have the time right now, but I'm pretty sure that a lot of the round numbers being thrown around above are way off. Fossil Fuel plants use multi stage turbines, and I think they get far higher eff than what are being quoted.

-ERD50
 
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