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.

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.

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?

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. :)

"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.

"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.

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.

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.

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.

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!

First time poster and they pull out crazy numbers with no support... don't feed the troll.

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.

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??

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).

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.

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).

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.

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.

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.

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)

Eric E wrote: 4) A heavy burden on the electrical grid due, in part, to the electrification of transportation will force newer, more efficient power plants into production financed by the displacement of oil.

I do not think the electrification of transportation will force newer power plants into production. Peak to valley ratio of the grid energy requirement is about 1 to 0.5. Take FP&L's 24,000MW capacity, for example, if this maximum capacity is just enough to meet the peak demand during the summer, the off-peak demand should be 12,000MW. Let's be more conservative since many people there keep the AC on during night, and increase this number to 16,000MW. Still this means FP&L has 8,000MW of surplus during off-peak hours. The Volt needs about 2KW of power for 4 off-peak hours to charge its battery pack from 30% charge to 80% charge. Therefore, FP&L can support 4 million Volts without building new power plants. The number increases to 8 million if charging hours are staggered to two 4-hour sections.

If this happens FP&L will be very happy since it earns money from otherwise wasted energy improving its bottom line. (It is dumping a lot of energy into the ground during off-peak hours to synchronize all the generators on the grid.) Also, this means reduction of CO2 emission since Volts on the road mean less number of cars with ICE and no additional tail pipe emissions for at least 40 miles per vehicle.

Excellent point.

So what do we do with the extra $700 million/day?:)

and...

"It (FP&L) is dumping a lot of energy into the ground during off-peak hours to synchronize all the generators on the grid."

Please explain...

Eric,
Unlike DC power sources such as batteries AC generators cannot be connected together in parallel unless they are synchronized. In addition to voltage their frequency (phase) must be precisely matched. Force of water or steam drives generator’s turbines. When energy demand gets higher, the turbine (rotor) gets heavier to turn, or vice versa. When a generator is rotating at a speed sending out 60Hz, 10,000-volt electricity, for example, its speed becomes slower (lowering frequency and voltage) as demand gets higher unless the water or steam flow increases. However, water or steam flow cannot be controlled quickly and precisely enough to respond to ever changing demand. So, a portion of output from a generator is discharged into the ground to stabilize the demand since electricity can respond quickly and precisely. Even though the water or steam flow is lowered (though slowly) for the reduced demand during off-peak hours, still the grid has to dump a lot of energy into the ground. This is the reason why utility companies charge 1/3 to 1/5 of day rate for off-peak hours. They are just happy to sell the electricity (at whatever price) that they have to waste otherwise.

If 4 million Volts are not realistic right away, then we can make stationary UPS’s using the A123 battery pack so that we can store the off-peak energy and use it during peak hours by cutting our home off from the grid, thereby reducing the burden on the grid during the peak hours. If FP&L's 24,000MW max capacity is short by 1,000MW causing black/brown outs during peak hours of hottest days of summer in Miami, for example, then FP&L can have the UPS installed at 1 million or so households, which is cheaper and faster than having to build a new nuke plant.

90% of my driving is single occupant with a 40 mile round trip. If the goal was a 50 mile round trip with two occupants then my numbers would be more like 95%. Why should I drag around another engine for less than 10% of my driving? I could either own or rent a vehicle for those special trips. I can't believe that mature adults couldn't understand this logic.
I understand that cuts out the petroleum industry, but we don't have buggy whips in our vehicles either.
Save the cost, save the weight, save the space, save the earth!

Well, if you are going to get all sanctimonious why don't you get yourself a bike if most of your driving is such a short distance? That would save the earth even more! ;)

I think the hybrid approach is more likely to appeal to the masses who would like to save the earth AND have the freedom they had with their old-technology cars. Don't worry, there will be quite a few all-electric options out there by 2011.

G35X

We will need to see some verification of your supposed electricity grounding during off-peak periods. Certainly not anything I am familar with.

You are correct, that in the grid, power is generated as 3-phase AC, and all the generators in the grid have to be "synchronized", such that they all become electrically "coupled" together (all rotate at exactly the same speed). For Florida, the grid is controlled by the system ISO (independent system operator) for the region (FRCC). I approximate summer capacity of the system is 53,000 MW (this equals about 71 million horsepower).

http://www.eia.doe.gov/fuelelectric.html

Since all these turbine generators are electrically coupled together, I estimate the system has about 20,000 tons of rotating machinery coupled together. When you flick on a big motor and its dims the lights, that's due to current draw in the local power lines. The 20,000 tons of rotating equipment doesn't flinch.

You seem to indicate that the machinery can't react to load changes, but that isn't true. First, the load changes in a large grid are typically not sudden, but happen at a rate of several percent per hour. But even in emergencies, a steam turbine can trip off line in less than 0.05 seconds (if a coupling breaks while the steam turbine is producing 500 MW, it will overspeed to destruction in less than a second, like driving full speed in a car and depressing the clutch). So I don't buy your theory of the equipment being too slow to adjust to the load. For a better look at a system's operation, see the CA ISO.

http://www.caiso.com/

Here you can see the power used in the grid on a daily basis. Its low was about 20,000 MW at 3 am, and the peak was almost 30,000 MW.

For the grid, nuclear plants are operated at full load around the clock. Next are coal plants which typically operate at full load during the day, but operate at part load in the evenings. Many natural gas combined cycle power plants start-up in the morning and shutdown in the evening as power demand decreases. Other forms of power (wind, solar, hydro) are added when it is available.

Note that most power plants have their best efficiency at full load.

At night, utilities have excess capacity that is either at part load (which is inefficient) or shutdown. They would like to find ways to even out the load demand, so that they can operate 24/7 at full load. Thus they provide incentives for customers who will agree to take "off-peak" power.

Note that as the system load becomes steady, the utilities will want to build more nuclear plants and coal plants, because of their low fuel costs. FP&L petitioned within the last year to build 2 new coal plants, but was denied by the FL PSC due to uncertainties regarding CO2 emissions. They have since petitioned for two new nuclear plants and have the FL PSC approval.

http://www.fpl.com/

With the Volt using 6 hours to charge 8 kwh into the batteries, the demand is 1.33 kW. Therefore, 1 million Volts, all charging at night, would add 1330 MW of load. As you can see in CA, between 11 pm and 5 am, this added load would result in a system load between 21,000 and 26,000 MW, well below the daily peak of 30,000 MW.

Since this load demand is indicative of other US ISO's, the current electrical system in the US has a great deal of capacity to charge electrical vehicles like the Volt during off-peak hours.

Can I then therefore assume that three phase AC provides 1/3 more current over the same size wire than single phase?

Is that the benefit and reason for three phase?

Sorry about all the questions but this is fascinating.

All this energy dumping talk has me wondering. I thought the grid already had lots of storage capability already in place to handle fluctuations in power consumption and production. We have capacitors (for quick changes), generators, battery banks, LPG plants that can fire up quickly and my personal favorite pumped storage hydro that can accept huge amounts of excess energy to move water up to higher reservoirs for later use (man-made hydro).

I wish I had access to a grid expert that knew most of the workings including the amount of dumping, storage, types or storage, future expansion plans, high voltage powerline infrastructure, etc. Is there such a guru around? If so, please jump in once in a while and clear up the misunderstandings.

My vision of future smart grids consists of mostly solar (both thermal and PV), wind, free-hydro and fossil fuel backup for the generation side and pumped storage hydro, advanced batteries, compressed air storage, biodiesel and other technologies (possibly even hydrogen) for the storage side. While I could put hydrogen and biodiesel on the generation end I think of them more as carriers of energy.

Of course we would use our existing infrastructure because it will take a long time to build out the new grids but I feel we need get off of fossil fuel burning as quickly as possible (even if that is 50 years from now). We do have a few hundred years of coal remaining but when compared to solar thermal it's just plain filthy.

What I would really like is a good debate on why we can't start building out massive amounts of pumped storage hydro. We already have quite a lot but if we are going to seriously use renewable sources of energy we are going to need a lot more. This infrastructure can be useful for hundreds of years and can be built just about anywhere. I'm aware that our natural, free-hydro resources are just about fully utilized but pumped storage hydro is a different animal, basically two huge reservoirs of water separated by a few hundred feet in elevation. The turbine generators are efficient and last for an unbelievable amount of time (new turbine designs use water bearings). Anyone? We could build these things out and make them as beautiful as Roman aqueducts. Good old fashion public works projects that would use US labor building useful US infrastructure. The disadvantage is that evapoation reduces the efficiency of the system but if you build them in rainy environments they can recover a lot of that loss. Even with evaporation pumped storage systems are over 70% efficient. They are clean, environmentally safe, technically simple, can provide huge amounts of power for long durations and can be turned on in a few seconds.

Bill,
Not that 60% vs 70% changes the argument, but the attached link shows the efficiency improvements for several new combined cycle gas-turbine power plants in Japan and 60% is right at the state of the art; so your numbers are right. But at 85%, hurrah for cogeneration; especially if the steam heat replaces an oil burner.

http://www.power-technology.com/projects/yokohama/

So with coal at 40% efficiency and a modern natural gas plant at 60%, then a Series Hybrid vehicle with a 40% efficient on-board turbo-diesel gen-set sounds really good. If the gen-set runs constantly, it allows you to downsize the battery pack to just a few kW-hrs; maybe $2000 of NiMH or $600 of SLA (sealed lead-acid) batteries, but you still get THREE-TO-FOUR times the fuel economy!! Both Azure Dynamics and AC Propulsion advertise over 90% efficiency for their electric drive systems from battery to wheels, so overall the Series Hybrid is 36% efficient whether it's driving in the city or on the highway, while a gasser averages 10-12%. Plus regenerative braking and eliminating idling losses easily adds 20% more, so in reality it's 43% vs 10-12%.

THIS MAKES A 25MPG CAR INTO A 100MPG CAR!

CAN SOMEONE EXPLAIN TO ME WHY WE HAVEN'T BEEN DOING THIS FOR THE PAST 50 YEARS !?!? The cost to build such a "non plug-in" Series Hybrid has to be dirt cheap (remember an AC induction motor only has ONE MOVING PART). How could the Big Three overlook a way to make a $5000 car for so long?

Dr Mark


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.

BillR,
Not being an insider of the industry I cannot show hard numbers as to how much energy is dumped into the ground. But, automatic voltage regulator (AVR) and neutral-point grounding to maintain quality of product on the grid operate by wasting energy. If you say the following equation is correct, I will be happy to retract what I said:

energy generated = energy billed + energy lost in transmission by resistive and capacitive components + energy used internally

If the left side is greater than the right side, where does the difference go?

To cover the base load, nuke plants and coal-fired plants (and water current plants) are always running at their maximum or close to maximum capacity because adjusting their output is difficult. Much easier to adjust or even shut down are gas-fired plants, oil-fired plants and hydro (including pump-up) plants. Yes, as you pointed out, the flywheel effect of the generator rotors absorbs short-term fluctuations of demand. It is also possible to adjust output with some preparatory time (30 minutes?). Here comes the art of power demand prediction. You forecast demand in the coming 24 hours (?) and fine tune the output on the fly 30 minutes (?) ahead of time. I think power plants generate a little bit more power than the prediction requires and dump the excess as buffer. I looked at the California ISO site. Thank you for directing me there. I noticed forecast is very close to the actual. What I did not understand is why they maintain the available power so high if the forecast is so accurate. Maybe they cannot shut down some of the big plants. Then, where does the excess go? Also, I do not understand the reason why they tell the public by the Conserve-O-Meter that conservation is helpful even though demand is so much lower than the available power. From the business standpoint they must want to keep the consumption as close to the max as possible.

Anyway, the situation will change dramatically thanks to GM/A123, Mitsubishi/GS, Subaru/NEC and Toyota/Panasonic alliances, which will bring us high-capacity, low-cost batteries. By using those batteries we can make high-capacity UPS’s, with which we store enough energy during off-peak hours to let us off the grid during peak hours. In this way we can shave the peak thereby reducing the peak demand so much so that eventually we can decommission some of the most offending coal-fired plants. This is quite a contrast to having to build more new (nuke) plants. Just think of the economic and employment opportunity in the manufacture and installation of the UPS, if we are to make and install, say, 5 million of them nationwide to shave some 10GW (more than 10 nuke plants' capacity) of power from the peak.

In addition, we are witnessing improvements in efficiency of solar cells. Mitsubishi Electric made announcement about a month ago that they achieved 18% efficiency. Even more encouraging is the UoD/DuPont cell, which is said to be more than 40% efficient.
By combining these solar cells on our roof, the UPS and off-peak charging we can be off-grid for a good part of a day.

In addition, we are witnessing improvements in efficiency of solar cells. Mitsubishi Electric made announcement about a month ago that they achieved 18% efficiency. Even more encouraging is the UoD/DuPont cell, which is said to be more than 40% efficient.
By combining these solar cells on our roof, the UPS and off-peak charging we can be off-grid for a good part of a day.

Don't forget that these technologies you mention are still too expensive to produce when compared with other alternatives. Nanosolar is the most advanced solar technology that's in mass production today (started a few months ago). Instead of semiconductor fabs they use a printing press like manufacturing process. They claim to be able to produce at 99 cents per Watt. At this cost PV solar is a no-brainer alternative. The past killer of solar was not the efficiency but the cost. We have enormous solar resources here in the US. Even at 5% efficiency we could easily provide all of our energy needs and most people wouldn’t be aware of the loss of desert. Now that a cheap manufacturing method has been brought to market we can roll this stuff out like newspapers.

Expect huge news on this soon. Something like: Government: Nanosolar, here is 100 Billion dollars please build as many solar factories as humanly possible and dedicate the entire production to covering our deserts. Nanosolar: Will do boss.