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What is the actual energy consumption to fully charge this vehicle? It would seem that one would have to account for energy generation (coal, gas, nuclear), stepping transformers, grid loses, and conversion back to household power to charge. Is there a rule of thumb like the power is 3/4 or 5/8 what was generated at the power plant to charge this vehicle?

Just curious. I am sure some people may be concerned that the amount of CO2 and ozone created by generating the electricity and passing it through the grid is about the same as an ICE.
 

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Yes! Many people are interested. In fact, it's the number one argument naysayers use to distract people from EVs.

I can rehash what has been said a million times. Things like it's easier to clean the exhaust from one power station than to clean the exhaust from a million car exhaust pipes but that doesn't seem like a strong enough retort for some. Makes logical sense to me. I could also say that the electrical motor system in an EV is around 95% efficient compared to around 30-40% for an ICE. Nope, not good enough argument. How about that as we add more solar farms and wind farms to the grid the amount of CO2 continues to go down until we are completely on renewable resources. Nope, the naysayers say that renewables are too intermittent and can only provide 10% of base load. They don't even consider proven pumped storage hydro or any of the storage options. They simply say it is too expensive and cannot be done. Yeah they may be more expensive compared to old fossil fuel technology with it's paid-for infrastructure but how do they ignore the benefits? It seems as though the naysayers are reaching for any straw they can grab in order to find anyway to defend their religious beliefs regarding the use of non-renewable resources. It's very interesting and probably critical to how people have survived today. A person can believe in an idea or person and follow that idea to their death, even in the face of insurmountable odds. Hummmm.

Anyway, The CO2 levels for EVs, considering the whole chain, are lower. Even if they were not the electrification of the automobile will help us get out of the oil nightmare we are in. Even if that were not the case it may help us manage the eventual decline of non-renewable sources of energy. Please don't say they will not decline. They will decline because of the basic definition of non-renewable. Even that extremely conservative way of thinking is enough for us to get going.

I know that did not satisfy your question. Nothing I could say would ever satisfy some people and their beliefs. My hope is that the majority of people will understand the situation and that will be enough to get the policies and markets moving.
 

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Good enough for now

We are having issues in our area (S E Michigan) related to improving the grid - which is getting lots of resistance. My concern is that if the grid is not improved, what effect does mass vehicle electrification have on the current infrastructure?

Also, our area had strong interest in ethanol and E85, but in the past 2 years interest has gone down for a number of practical issues that still need to be over come.

I guess my ideal solution would be to find a way to turn garbage dumps into energy sources - either in generating electricity or a biodiesel. If used to generate electricity, there is still the issue of upgrading the grid - the 3 day blackout from a few years ago is still fresh in my mind.

On another practical note, I like the idea of an electric vehicle with an ICE. Who wants to get caught in a blizzard with just an electric motor?
 

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Methane from Garbage dumps

We are having issues in our area (S E Michigan) related to improving the grid - which is getting lots of resistance. My concern is that if the grid is not improved, what effect does mass vehicle electrification have on the current infrastructure?

Also, our area had strong interest in ethanol and E85, but in the past 2 years interest has gone down for a number of practical issues that still need to be over come.

I guess my ideal solution would be to find a way to turn garbage dumps into energy sources - either in generating electricity or a biodiesel. If used to generate electricity, there is still the issue of upgrading the grid - the 3 day blackout from a few years ago is still fresh in my mind.

On another practical note, I like the idea of an electric vehicle with an ICE. Who wants to get caught in a blizzard with just an electric motor?
Garbage dumps generate a lot of methane from the decomposing material. I have seen in the past where companies bury pipes into the dumps to tap the produced methane. The University of New Hampshire is doing just that. On NPR: http://www.npr.org/templates/story/story.php?storyId=6620706

Now, burning methane produces CO2 and H20. You burn the Methane in high efficiency engines to generate electricity. You capture the CO2 and sequester it. You capture the H20 and use it for drinking water. Later when methane production becomes low or stops, you mine your garbage dump for the metals that had been thrown away and recycle them. Then you turn it back into a garbage dump, fill it up, then do the same thing again. A completely renewable source of energy from the ever expanding amount of trash we generate.

I'll take a cut of the profit. :)
 

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"What is the actual energy consumption to fully charge this vehicle?"

If you google wells to wheels, you can find studies on the energy usage of various platforms. Here's one:

http://www.transportation.anl.gov/pdfs/TA/273.pdf

Looks like electric vehicles are about the lowest, and as Texas points out, we can make electricity many ways. To me there is no question that EREVs are what we need to move to.
 

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"What is the actual energy consumption to fully charge this vehicle?"

If you google wells to wheels, you can find studies on the energy usage of various platforms. Here's one:

http://www.transportation.anl.gov/pdfs/TA/273.pdf

Looks like electric vehicles are about the lowest, and as Texas points out, we can make electricity many ways. To me there is no question that EREVs are what we need to move to.
I suspect that chart hasn't incorporated the latest breakthroughs in thin film solar, solar hydrogen generators, solar alcohol generators, etc.
 

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There is a very thoughtful discussion of well to wheel efficiencies on Tesla's website. One common thing that is overlooked is the local energy mix. So, the emission issue should be looked at individually by those concerned. The energy poduction mix in most areas of the US greatly favor a grid charged vehicles versus ICE with regards to emissions. The are a select few areas where it is a tossup today, but will most likely favor EV's in the near future.
 

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Koz,

The Tesla site is heavily 100% BEV leaning, so they don't consider the latest thin film solar, solar hydrogen generator and solar alcohol generator tech. Even if they did, they are stuck on efficiency numbers, instead of cost numbers, so they will always prefer batteries, no matter how much batteries cost.
 

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physics suggests efficiencies are poor

every change in enery type creates losses... a coal / steam electrical plant is said to be around 40% efficient.....same as an internal combustion engine.

Now add electrical transmission losses ..5%, charger losses5+%, battery losses X 2 (charge and discharge)10+%, speed control losses 15%, electrical motor losses 10%, and the energy efficiency of an electrical car is probably less than 1/2 of an internal combustion engine vehicle.

And there are losses...thats why they need battery cooling, motor cooling, heatsinks ect.

Appling power directly to the wheels from the engine is by far the most efficient way.
 

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every change in enery type creates losses... a coal / steam electrical plant is said to be around 40% efficient.....same as an internal combustion engine.

Now add electrical transmission losses ..5%, charger losses5+%, battery losses X 2 (charge and discharge)10+%, speed control losses 15%, electrical motor losses 10%, and the energy efficiency of an electrical car is probably less than 1/2 of an internal combustion engine vehicle.

And there are losses...thats why they need battery cooling, motor cooling, heatsinks ect.

Appling power directly to the wheels from the engine is by far the most efficient way.
Did you just pulled those numbers out of your butt? Only half as efficient? LOL. Please show us the numbers you used for that calculation! Do you work for an Oil company?

Oh for reference go to the Rocky Mountain Institute web site and check out their calculations. They figure less than 6 percent of the energy in the gasoline is used to move the vehicle and less than one percent is used to move the person!
 

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US CO2 Emissions

Continuing to use ICE's does not get us off oil, and it does not reduce emissions. Criteria pollutants such as CO, NOx, and SOx are more effectively reduced at the power plant than at the individual vehicle. However, an efficient hybrid at 45 mpg will produce less CO2 than a EV that gets its power exclusively from the most inefficient coal plant. See the following link:

http://www.nrdc.org/energy/

In 2006, the US emitted 6.0 billion metric tons of CO2 into the air. Of that total, 2.0 billion was related to transportation, and 2.4 billion came from power generation.

If you looked further into the power sector, 2.0 billion of the 2.4 billion came from coal-fired power. Therefore, reductions of CO2 will rely on a combination of electric vehicles (which will reduce the emissions from the transportation sector) in conjunction with a more efficient grid, including clean coal plants. The next generation coal plants will capture most (~90%) of the CO2 they generate and sequester it underground.

With the implementation of a carbon tax (tax on CO2 emissions), older coal plants will produce more expensive power than the next generation coal plants, and will ultimately be retired and replaced with more modern generation.

Although renewables will play a role, the projections are that they will only provide up to 15% of the total electricity. Coal and nuclear will still be the major power providers.

Sometimes I don't think many of us realize how much energy we consume in this country. We refine approximately 15 million barrels of crude oil per day (that's 630 million gallons per day) and also import gasoline and other petroleum products. In addition, our natural gas consumption is about 75% of the petroleum energy equivalent, and we also consume about 2.8 million tons of coal per day.

The endeavor to eliminate fossil fuels and reduce CO2 will not be a simple one.
 

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Please correct me TEXAS!

Did you just pulled those numbers out of your butt? Only half as efficient? LOL. Please show us the numbers you used for that calculation! Do you work for an Oil company?

Oh for reference go to the Rocky Mountain Institute web site and check out their calculations. They figure less than 6 percent of the energy in the gasoline is used to move the vehicle and less than one percent is used to move the person!
I guess my 25 yrs experience in developement of electrical power control means nothing. You can give ME the correct numbers.

And use some references that mean something such as published manufacturer data ( ie rockwell automation catalog ect) not rocky mountain institute that is looking for some suckers (i mean investers).

So the question is....why would i need a 1000lbs of batteries to get 40 miles if we have such great efficiencies??
 

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Double Check on Physics

every change in enery type creates losses... a coal / steam electrical plant is said to be around 40% efficient.....same as an internal combustion engine.

Now add electrical transmission losses ..5%, charger losses5+%, battery losses X 2 (charge and discharge)10+%, speed control losses 15%, electrical motor losses 10%, and the energy efficiency of an electrical car is probably less than 1/2 of an internal combustion engine vehicle.

And there are losses...thats why they need battery cooling, motor cooling, heatsinks ect.

Appling power directly to the wheels from the engine is by far the most efficient way.

Let's use your numbers for electrical efficiency. Therefore, the energy input from coal to the Volt is (.40)(.95)(.95)(.90)(.85)(.90) or 24.85%. Note that once the Volt has this pure form of energy (electricity) it only requires 200 Wh per mile of energy.

Although gasoline engines can be 35% efficient (40% is somewhat high), they seldom operate at their most efficient point. Usually they are at a low load condition. An example, the Yukon SUV only requires 30 hp to cruise at highway speeds on a level surface, yet it has an engine rated at over 300 hp. The following link to a DOE website indicates that only 15% of the energy in gasoline actually drives the vehicle.

http://www.fueleconomy.gov/feg/atv.shtml

So, it seems to me that 25% of the energy from coal is better than 15% of the energy from gasoline. Not only that, the economics bear it out. Compare the fuel costs for an average sedan at 25 mpg that buys gasoline at $3.25 per gallon, versus the Volt which travels 40 miles on 8 kWh with a national average of 8.7 cents per kWh. The energy costs are 13 cents per mile for gasoline and 1.74 cents per mile (about 7.5 times more).
 

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Yes, what he said and here is a link with a more detailed analysis of car and powerplant efficiencies. How about we start there?

http://www.electroauto.com/info/pollmyth.shtml


It goes into details about not only the car's efficiency but also how the energy is generated. Here is a quote:

"Even though the GM EV1 has 43 percent fewer BTUs after electricity generation, it can be driven almost 350 miles farther because the vehicle is more efficient than the Acura. In fact, the GM EV1 has the gasoline equivalency of 69 mpg (23) even after factoring in losses from electricity generation and charging!"

The link I provided is only a starting point. The only number you provided us is that you worked with electrical systems for 24 years. Let's dig as deeply as possible to uncover the truth.
 

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No Guessing Required

No more guessing, there is actual data to compare an electric drive vehicle and a gas powered version of the same vehicle. The Toyota RAV4 was produced in 1999 thru 2002 in both varieties and you get 250 Watt-hrs / mile vs 25 MPG (average city-highway). I just checked my electric bill; Florida is by no means a cheap state for electricity and I pay under 9 cents per kW-hr. So if I can get 4 miles on a kW-hr that's 2 1/4 cents per mile vs 12 cents for the gas-powered RAV4 ($3.00 / 25 = 12 cents / mile).

So what's the explanation? Is FP&L secretly the world's largest charitable organization? Florida averages 22% petroleum and 28% natural gas for power production, so their fuel costs can't be that much less than you and I would pay for heating fuel. No, the truth is that 40% is a lousy example of electric power generation efficiency, a modern compound cycle gas turbine is 70% efficient, and distribution losses are only about 5%. So compare that to 15% efficiency on the highway, and less than 10% efficiency in town (even less if you consider non-regenerative braking as an energy loss) and VIOLA, there's your FIVE-to-ONE ratio.

The FIVE-to-ONE cost difference is even harder to explain considering FP&L makes a profit, maintains and builds distribution infrastructure, etc, etc. But most consumers don't care to know any more than this; $.60 vs. $3.00 (Duh!). So, don't worry about vehicle efficiency; it's there with at least a 4-fold improvement; Let's just get building these things.

Some good sources for more info are:
http://autoxprize.typepad.com/axp/2008/01/computing-mpge.html
http://www.freedomformula.org/ (click the "Why are Electric Cars Better" at the top of the page)
http://en.wikipedia.org/wiki/Toyota_RAV4_EV
http://www.fr

Dr Mark

Let's use your numbers for electrical efficiency. Therefore, the energy input from coal to the Volt is (.40)(.95)(.95)(.90)(.85)(.90) or 24.85%. Note that once the Volt has this pure form of energy (electricity) it only requires 200 Wh per mile of energy.

Although gasoline engines can be 35% efficient (40% is somewhat high), they seldom operate at their most efficient point. Usually they are at a low load condition. An example, the Yukon SUV only requires 30 hp to cruise at highway speeds on a level surface, yet it has an engine rated at over 300 hp. The following link to a DOE website indicates that only 15% of the energy in gasoline actually drives the vehicle.

http://www.fueleconomy.gov/feg/atv.shtml

So, it seems to me that 25% of the energy from coal is better than 15% of the energy from gasoline. Not only that, the economics bear it out. Compare the fuel costs for an average sedan at 25 mpg that buys gasoline at $3.25 per gallon, versus the Volt which travels 40 miles on 8 kWh with a national average of 8.7 cents per kWh. The energy costs are 13 cents per mile for gasoline and 1.74 cents per mile (about 7.5 times more).
 

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Power Generation

Dr. Mark,

I'm not sure where you got the 70% efficiency for a combined cycle power plant, but state-of-the-art plants of this type have efficiencies of 55 to 60%, with 60% the absolute maximum. Most use natural gas for fuel, and because they can contract for large quantities of gas over long periods of time, they can get much better rates than you as a consumer (where you have to pay for the local gas company's pipelines, maintenance, profit, etc.).

Also, FP&L has 20% of its 24,000 MW capacity in nuclear, and the fuel cost for nuclear power is about 0.5 cents per kwh. The capital and maintenance costs are typically the major costs for these facilities.

But you are correct, the electric cars are very efficient, and the generation of power at large central stations, utilizing a diverse portfolio of fuels, provides lower cost energy for the propulsion of automobiles than conventional cars with gasoline.
 

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Efficiency is the Key So Let's Get it Right

Bill,
The 60% figure is for a Carnot cycle gas-turbine, but most plants now employ a compound Carnot and Brayton cycle and as this Wikipedia article claims the efficiency for these can get as high as 85%; so that's about SIX TIMES a gas IC engine in a car.

http://en.wikipedia.org/wiki/Combined_cycle

At 8 to 15% average efficiency the gasoline engine just SCREAMS for improvement. Just raising automotive drivetrain efficiency to 50% (wells-to-wheels total) means your 25 MPG car becomes a 100+ MPG car, so efficiency is the whole reason for the changes we are talking about.

Your figures for nuclear power are pretty damning, aren't they? Are we really selling off this country piece by piece to the Arabs just to avoid facing the challenge of containing and disposing of nuclear waste. But whether it's fueled by nuclear, clean-coal, or gasahol, electricity is the way to go because NO ONE can cut off all sources of energy. And as the cost comparison proves, the power companies will find the lowest cost mix of these fuels without anyone twisting their arms.

Dr Mark

Dr. Mark,

I'm not sure where you got the 70% efficiency for a combined cycle power plant, but state-of-the-art plants of this type have efficiencies of 55 to 60%, with 60% the absolute maximum. Most use natural gas for fuel, and because they can contract for large quantities of gas over long periods of time, they can get much better rates than you as a consumer (where you have to pay for the local gas company's pipelines, maintenance, profit, etc.).

Also, FP&L has 20% of its 24,000 MW capacity in nuclear, and the fuel cost for nuclear power is about 0.5 cents per kwh. The capital and maintenance costs are typically the major costs for these facilities.

But you are correct, the electric cars are very efficient, and the generation of power at large central stations, utilizing a diverse portfolio of fuels, provides lower cost energy for the propulsion of automobiles than conventional cars with gasoline.
 

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Efficiency Clarification

I looked at your link at Winkipedia. In the article, they indicate a the following:

"The thermal efficiency of a combined cycle power plant is the net power output of the plant divided by the heating value of the fuel. If the plant produces only electricity, efficiencies of up to 59% can be achieved. In the case of combined heat and power generation, the overall efficiency can increase to 85%."

So for a pure power plant (electricity production only), the efficiency can be up to 59%. This in the important efficiency to remember, as it is the conversion of fuel to electricity, which is what the Volt requires.

Combined heat and power (CHP) applications are also referred to a cogeneration facilities. A typical CHP facility might be a combined cycle power plant located at a paper mill. Besides producing power, the facility supplies medium pressure steam to the paper mill to dry paper coming off the process. Now the paper mill doesn't need to burn fuel to produce steam.

In this scenario, the actual fuel utilization factor increases (up to 85%, as mentioned in Winkipedia), however, the electrical efficiency decreases, as the medium pressure steam is used for heating instead of power generation in a steam turbine.

CHP is a great technology, as it helps us reduce the use of fuels, however, CHP efficiencies are not the same as a power plant efficiency, so they can't be compared directly to an ICE. Note that even ICE's can be used in CHP applications, where the heat from the coolant and exhaust can be used to make hot water. One application I know of was an ICE driving a generator at a glass plant, where the glass had to be washed after it was formed and cooled. I'm sure the CHP efficiency for this ICE application could be 80+% as well.
 

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People have been debating this issue for years, but we must look at the long term results of electrification.

1) We spend $700 million/day with OPEC
2) Our electrical infrastructure is aging and inefficient
3) New alternative technologies are becoming more affordable
4) A heavy burden on the electrical grid due, in part, to the electrification of transportation will force newer, more efficient powerplants into production financed by the displacement of oil.

To me its obvious. (IMHO)
 
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