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How much loss of energy between power plant and house?
2

How much loss of energy between power plant and house?

How much loss of energy between power plant and house?

(OP)
I'm trying to put together an intelligent argument against the use of household-charged electric vehicles based on several factors including the inefficiency with which electricity is delivered to the home.  According to DOE reports, nearly 70% of the US electrical production is still coming from fossil fuels, so that little tidbit combined with how much of that energy actually reaches your house might make a rather persuasive argument.

Can someone help me out with a reference or website that might help me find out how much of the juice produced at the plant makes it to the average home?

RE: How much loss of energy between power plant and house?

I think you are barking up the wrong tree.  Transmission losses in the electrical system are quite low.  Because high voltages are used, resistive losses are greatly minimized.  

Don't forget to factor in the energy it takes to haul the gasoline to the gas station.  

I suspect recharging an electric car and running it via an electric motor powered by batteries is much more efficient than burning gasoline in the engine.  

The power plants burning fossil fuel are more efficient than an IC engine, also.   

RE: How much loss of energy between power plant and house?

You're probably looking at 7 to 10% as a typical range of system "transmission" losses for the U.S.  This range includes losses in the distribution system as well as the transmission system.

RE: How much loss of energy between power plant and house?

(OP)
Thanks for the replies.  I know that they start out at really high voltage, but then they're stepped down in at least two steps.  Doesn't it lose a bunch?

Fossil-fuel power production according to the EPA and DOE is only about 1/3 efficient; that is to say, only 1/3 of the stored energy in the fuel gets translated to electrical energy.  That's very similar to a hydrocarbon-burning vehicle engine.  I have to think that 1/3 efficiency at the plant, minus 7-10% in transmission, minus a bunch wasted charging the batteries in the car, minus the notable inefficiencies getting the power from the battery to the motors then to the ground still seems like such a waste comparatively.  Thoughts?

RE: How much loss of energy between power plant and house?

The better CCGT generating stations have over 50% thermal efficiency. Your car isn't going to beat that.
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: How much loss of energy between power plant and house?

The power utility has an incentive to reduce the losses to maximize its profit.  Although the world is full of compromises, I cannot imagine utilities have not looked at cost effective ways to minimize transmission losses.
 

Don Phillips
http://worthingtonengineering.com

RE: How much loss of energy between power plant and house?

I remember seeing a paper on this topic published by the Society of Automotive Engineers a few years a go.  They looked at the "well to wheels" efficiency of a number of drive trains.  I believe they found the gasoline/electric hybrid was the most efficient, followed by the battery electric vehicle.  
John

RE: How much loss of energy between power plant and house?

(OP)
Ok, 'nuf said.  Thanks for the numbers.

RE: How much loss of energy between power plant and house?

Regarding transformers - most efficient energy conversion device in existence.  Efficiencies well over 99% so not much is lost there.  

Car engines are much less efficient than even a conventional fossil-fueled steam  plant.   All that hot coolant flowing through the radiator is basically waste heat.   

RE: How much loss of energy between power plant and house?

I think IC cars are about 7-10% efficient.

Even with all the losses a battery car comes out ahead in the carbon game.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

Effecency is one thing, what about the cost of the fuel. Or the deversity of the fuel mix that creates the lower cost.

Or what about the lower maintenance of the components, other than the batteries. Not to say anything about the long life of the elements of the power grid, and the reliability.

Very few IC engines can get close to four or five 9's for reliability.

 

RE: How much loss of energy between power plant and house?

You are missing one other important factor and that is time of day considerations.  There are certain times of day that the power companies have trouble meeting demand and don't need the added load of charging electric vehicles but that said, there are other times when the charging of electric vehicles would be very beneficial to them such as in the middle of the night when their demand is very low and they have trouble keeping units on line.

I have held and stated in these fora that when the power companies can send a signal via a multiplexer to a charger at the consumer's house to operate it in the middle of the night (or whenever they want to) when they need load in order to keep the units on line and operating at optimum efficiency and give a discount on the cost of the power sold at that time, the electric car will become a reality.  Being the sluggish monolithic dinosaurs that the electric utilities are, I don't expect it in my lifetime, however.

Your answer came from jfpe.  Google his words "well to wheel" and you will find what you need to know.  It has been studied exhaustively and documented well.  There are lots of losses getting that gallon of fuel to the fueling station.

rmw

RE: How much loss of energy between power plant and house?

rmw, look for AMI (Advanced Metering Infrastructure) to make a tremendous change over the next few years.  The utility I work for will have two-way communications with all residential meters within the next few years.

RE: How much loss of energy between power plant and house?

David,

That is encouraging.

So would that give the ability to start/stop a charging device at will as I have suggested?  And, would it give the ability to offer 'time of day' tariffs?  Is there any hope of the utilities getting in on this thing?  They could put the electric car on the map if they got on board with the concept IMHO.

rmw

RE: How much loss of energy between power plant and house?

Yep, all of that and more.

RE: How much loss of energy between power plant and house?

I would assume that a rado signel could be used simular to the way utilities use to turn on distribution capacitors.

The technology is there, but so far the demand isen't.

As far as being sluggish monolithic dinosaurs, utilities are very economic and much slower to rise prices compaired to many other industries. And again utilities are in a very long life cycle business which happens to be very capitial intensive (The last part is the barrier to new competion, which is why utilities are very regulated by goverment).



 

RE: How much loss of energy between power plant and house?

I think you should stop trying to form an opinion before you get the facts.  Internal combustion enegines (the Otto cycle type) are terribly inefficient--the better motors might get perhaps 20% efficiency (with turbos, etc).  Diesels do better due to the higher compression ratio and greater heating value of the fuel.  NO utility scale power plant has efficiencies this low! Hydro power is very efficient (over 80%), thermal power plants are in the high 30 percent range, combined cycle power plants are usually above 50%.  
Why is electricity relatively inexpensive (compared to gasoline)?  Think about it.  In 1920 a kw-hr cost 22 cents, today it might be 12 cents in a high priced market.  Yep, we know how to make electricity in an efficient manner.  The blended efficiency of a utility with a good mix of generation types is going to be near the 50% mark. Heck, just a few days ago the Mid-Columiba was "selling" electricity for -$1 per MW-hr...that is right, people were paying other people to take their electricity.  Now, that doesn't happen that often, but when was the last time someone paid you to take gasoline, hmmm, let me think, oh, that's right, never!

As other have noted, the losses in transmission vary from perhaps as low as 3% to perhaps 7%.  Various utility tariffs typically have them at no more than 5%.  Distribution losses might add a few percent to this, but no more than this.  

Your attempt to show that electric cars are NOT efficient is doomed to failure--it simply isn't true at all!  You need to spend some time looking at unit conversions and convert kw-hr (of electricity) and BTU (of gasoline) to a common basis and compare the "mileage" on a cost basis.  What you will find is that an eletric car gets "gasoline cost per gallon" of about ~$1 per gallon.  In other words, electric cars simply crush gasoline fueled automobiles--the actual figures depend on electricity costs, type of electric car, etc.  The drive motor on an electric car is over 85% efficient.    

The reason electric cars haven't hit it big is due to a the limited range that present battery technology offers and the fact that oil has historically been quite inexpensive.  For a short commute electric automobiles are quite effective--the problem is that big automotive companies have yet to make the neccessary tooling switches to make them in large numbers.  GM's EV-1's were basically hand made.  With gasoline at the $5 a gallon mark you should expect to see more conversions of internal combustion engines to electric motors occuring--simple economics will drive this.  You can recover the $5k to $7K that the conversion will cost you quite quickly.  

Bottomline:  Electric cars are much more efficient than internal combustion motor powered automobiles--the free market clearly demonstrates this through the common unit of $$$$.

RE: How much loss of energy between power plant and house?

I am so surprised that in  this forum, almost every body agrees that Electc. car is more ..... than Gaslin.. car...
But Ignore one important factor:
I don't know the other places, but in North Amerca, almost all major transmission facilities was built back to 40 years ago. One thing will happen is that after another 10-20 years, you will hate to pay your elect. bill when you see it.

The company I work proposed 5 Billlion reinforcement last year onlu on some cosmatic changes on our T/D system. I would expect after 10 to 20 years when we really start to upgrade all our 230/500kV system due to the aging and/or increasing transfer issues it may go up to 50 Billion. At that time, you will have a second thought of what your guys just said.  

RE: How much loss of energy between power plant and house?

QBPlanner,

Transmission lines don't get less efficient as they get older.  

Most of the grid improvements will be required regardless of electric cars or not.   

The main point of discussion was efficiency, not cost.    

RE: How much loss of energy between power plant and house?

Hey here's an idea, lets send a wireless signel to allow electric cars charge only when the wind is blowing.
That would be a good way to balance out the effects of wind farms.

 

RE: How much loss of energy between power plant and house?

I belive power transmission losses were estimated at just over 7% in the mid 90s and I doubt that would have changed much now.  

I have to disagree with some of the numbers listed above:
-Modern Otto IC engines are 27-33% efficient under normal operating conditions.
-The later of most Rankin based power plants operate just under 40% thermal efficieny just for the cycle itself.  
-Since when is electricity cheaper than natural gas in the US?

Personally I dont think electric vehicles will ever become mainstream.  There is no possible infrastructure that will be capable of supporting them that can be built in the next 15 years and by then Im banking on the hydrogen economy taking over.

RE: How much loss of energy between power plant and house?

DPC:
I did not say T/L line get low efficient due to the ages.
Grid reinforcement get not much to do with how many elec. Cars plug in .

If one day I receive a bill with $2-5/kwh, I will think about if I have to charge my car or go get Gas.
efficiency get nothing to do with the cost , that is your opinion

 

RE: How much loss of energy between power plant and house?

Thermal power plants (i.e. Rankine cycle) plants are rated on throughput--i.e. fuel input to electricity output.  For example, Colstrip is /was one of the most efficient plants of its type, just around 39% of its energy input is turned into electricity (coal to electricity).  Thermal plants have high efficiencies in the furnance and boiler, it is that pesky condensation of steam that kills their efficiencies.  Ironically, wind turbines have about the same efficiencies as do thermal plants (no free lunch from Mother Nature it seems).

Electric cars are coming, and becoming more mainstream every day.  The fear that the utility I work for has is that at $5 a gallon for gas the electric cars will show up faster than we can plan for.  Our load curve will be flat and we will be short on resources.  I like the idea of using intermittant resources (i.e. wind) to charge the batteries on an electric car--just need the communications in place to make that work, perhaps a lower rate is needed as well.  

Otto cycle engines at 27 to 30% efficiencies?  Name one car sold that has that high of an efficiency--I want to buy it!  Atkinson cycle and diesels operate there, not Otto cycle engines.  That doesn't mean that Otto cycles can't get there--they don't yet however (in mass produced automobiles).  Presumably the high cost of liquid fuel will re-kindle the market for fuel efficient automobiles.  

Transmission losses are undergoing a slight downward trend--Kelvins Law indicates that lines should be sized based on a forward electricity price, at $100 MW-hr a fat conductor looks like a really good idea.  

I think the point here is that electricity is a more efficient way to do business across the board.  If it wasn't, then why don't we have gasoline motors in our washing machines, clothes dryers, hair dryers, etc.  It is the difficulty in storing electricity (you really can't do it) that keeps electric cars from being more mainstream.  Given that most Americans have a commute distance of less than 50 miles (round trip) it seems to me that the time for the electric car has arrived.   

RE: How much loss of energy between power plant and house?

There was an idea about using a rail guide on major highways that would allow charging while attached to the rail guide. Sort of like a single rail attachment where you don't have to steer for some distance (30 miles seem like a good number).
The problems there were trying to look at is what happens at the end if the driver was asleep (what happens now if you fall asleep while on cruse control)?

It has some advantages like everyone travels at the same speed (I would assume the speed limit), and cars could travel closer togather (no ones stopping).

 

RE: How much loss of energy between power plant and house?

In response to rmw (Mechanical), Where I come from much of the hot water heating is done by electricity. For at least 40 years the power company have had the ability to turn water heating On and Off with what is called a ripple relay Short pulses of high frequency (200Hz) are superimposed onto the lines. The early relays were mechanical devices tuned to respond to a certain pulse frequency. This allows them to smooth out the generator load with no noticable effect on the consumer. It's for sure they could use the same method for controlling your car charger.
Roy

RE: How much loss of energy between power plant and house?

Interesting discussion.

Aside from the infrastructure question (which is a HUGE point) it still doesn't make economic sense to go electric.  You can't recover the extra cost of the vehicle in fuel cost savings...yet.  In the US it doesn't even make sense to go Diesel unless you drive a huge amount.  And it will be a while before you can.  Many parts of the industrialized world have been dealing with high fuel costs for a long time.  Yet they haven't firmly embraced electic vehicles, although they have enbraced Diesel.

All references to low-to-mid teen efficiencies for Otto-cycle engines I have seen have been from groups with some interest in making the number look bad.  And, no, Wikipedia can't be used as an unverified source.  The EPA website shows a losses breakdown.  The way they get to high teen efficiencies is by blowwing 10-12% in idle.  That may be an issue in LA or Chicago, but it isn't where I live.  A conservative 85% of my engine runtime is spent at fixed highway speeds.  You can make the very valid point that idle losses aren't a loss with electric vehicles.  But you can't make a blanket statement about Otto-cycle efficiency without bringing specific usage into the picture.  

Keith

RE: How much loss of energy between power plant and house?

There's new battery technology on the way, nano-based litium batteries, that exceed 10x the capacity of standard lithium batteries.  If these can be mass-produced at comparable cost to existing lithium batteries, a Prius-sized (and prius-priced) battery would suddenly be an effective PHEV capable of driving 40 miles on a charge.

The problem remains when everyone in the US gets home and plugs in their cars simultanously on a hot afternoon... if we don't have TOD metering rolled out by then, new power plants built and infrastructure upgraded.  It won't be spread evenly, but concentrated in residential areas at specific times of the day.  I calculated last week (sorry, don't have the numbers handy) that in 10 years time, peak demand in residential areas will literally double unless consumers have incentive to place their cars on timers as opposed to topping off to allow evening trips...  And even then, it's going to be such a dramatic increase that the grid will fail.

We'll need a couple hundred new nuclear power plants to keep up with demand as well as upgraded infrastructure, lest we simply trade oil for coal, which is the most likely case.  It will be painful for pocos and consumers alike when major residential grid components start exploding and need replaced.  The only thing that will save the grid are the tens of thousands of industrial and commercial buildings out there with small diesel generators that will kick on when the frequency wavers and voltage drops and reduce load on the grid ;)  go go green!

RE: How much loss of energy between power plant and house?

One question, how can people plug in there car at home if they are at work? Or how can a business stay open if the workers are at home?
Somewhere there is reduction of business load at the same time residential load is growing.
Normally the summer load peaks, and the peaking plants operate, just after 5pm.
And given that plug in power (now) is from a power plug limited to 12 amps X 120 volts = 1440 watts, it's hard to believe such a massive jump that can't be handeled by existing + new peaking plants.
Granted that new peaking plants will need to be built, and currently that is about a 2 year consturction cycle.

 

RE: How much loss of energy between power plant and house?

I just don't see the problem.. The power company already controls when you can charge a car with NO communications other than your monthly bill!  You plug your car into a separate meter.  That meter is a time-of-use meter.  You draw from that meter before 7pm you get hosed big time!  The user or the car makers will put in timers to assure this doesn't happen.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

There are studies that show that the existing electrical grid and power production facilities could support something like 10 million plug-in hybrids right now.  I wish we did have more nuclear plants so if this is a way to get more, I'm all for it.  
 

RE: How much loss of energy between power plant and house?

As was mentioned above in previous threads, if this about efficiency of A) [Rankine cycle power plant output – transmission/distribution system losses – electric car losses] vs. B) [Otto engine powered automobile output (Wankel engine for you Mazda fans)] then the winner is system A.
  
If this is about cost and feasibility, the free market rules.  If it was COST efficient to have electric cars mass produced and driving on US streets then they would be.
 
By the way....there are several Load Management Systems deployed throughout various utilities with capabilities to remotely meter residential homes and also control residential loads i.e. turn off your water heaters, air conditioning units, etc. at designated times.  Initiating or turning on a system via these Load Management Systems would be no problem.
 

RE: How much loss of energy between power plant and house?

Quote:

If this is about cost and feasibility, the free market rules.  If it was COST efficient to have electric cars mass produced and driving on US streets then they would be.

This should be the way.  But is NOT reality.  Why?  Because it all comes down to a few dimwits,(note: all of Detroit), sitting in board rooms saying I don't think so..  Let's stick with what we have now, we made a lot of money with it a while ago..

I'd buy an all electric car tomorrow if it could do 80 miles 10 at freeway speeds.

I have about 10 friends who would buy them too.  None of us commute over 15 miles one way.  All of us have other, "long range" vehicles.

But all the makers seem to think any electric car is going to require 160+ miles and remote charging stations, etc, etc.   It's sad.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

Quote:

I have about 10 friends who would buy them too.  None of us commute over 15 miles one way.  All of us have other, "long range" vehicles.
GM found with their EV-1 that there aren't very many people like you and your friends that will plunk down a lot of dough for a second vehicle with a limited range.
 

RE: How much loss of energy between power plant and house?

That was what? Ten years ago?  And based on a cockamamie leasing program, too.  I think they found exactly what 'they' wanted to find, and now they are losing to Toyota..

I seem to recall many thousands of totally incensed people wanting to buy  EV-1s and buy their  leased EV-1s only to have GM demand them back so they could crush them all. One of the largest spasms of eco-stupidity seen in recent years.

That was also when gas was $1 a gallon.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

Quote:

I think they found exactly what 'they' wanted to find, and now they are losing to Toyota..

Now that's funny.  Sure, I see a few Prius on the road around here.  But not as many as you would think given all the hype.  There are Priuses sitting on the lot at the dealership (at least according to my local Toyota dealer's ad on the radio) so it's not like Toyota can't keep up with production.  And for my driving mix my '96 Saturn gets roughly equivalent mileage, at less than half the initial investment.

I'm with jghrist on the extra vehicle thing.  I certainly couldn't afford to have a special purpose vehicle sitting around.  If I could I'd probably do it.

The guys in Detroit are capitolists, just like most others in the US.  If their market research said that they could sell one million electric vehicles a year you would see one tomorrow, infrastructure be damned.   The market won't support the demand so they stay out.  Free-lance researchers are no dummies either.  They generally know what it would take for the public to accept electric vehicles.  You don't think there are a herd of people going after the Holy Grail as we speak?  It's pretty easy to say 'Well, just make a battery that has greater capacity' or 'Well, just don't drive so far'.  Its a little more complicated making it happen.

Keith
 

RE: How much loss of energy between power plant and house?

It's different around here I guess.  The town I live in has a multi month wait for a Prions(Prius).  I walk 8 blocks thru my residential area to work.  Last month on the way home I counted 14 Priusouseseses.  Approximately 2 per block and they're short blocks too!

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

There is a six-month waiting list for a Prius here at our local dealer in Oregon.  

Simply building what people want to buy right now is not a successful long-term strategy for an automobile company.  But even if GM should go out of business, the government will never let it happen.

I especially love Chrysler's pitch of $2.99 gas for three years as a way to unload their gas guzzlers.  As a commentator wrote, it like a drug dealer helping out a junkie with a special deal to keep him coming back with his money.  



  

RE: How much loss of energy between power plant and house?

Prions, Keith?  Aren't those the proteins that cause mad cow disease? smile

It is interesting how the availability (and presumably demand) changes so much in various areas.  I don't know if this is due to marketing, cost/value perception or environmental benefit perception.  For my money I'll wait for the affordable pure electrics.  In my mind the hybrids have their place.  It just happens to be the same place that the pure electrics fit.

dpc, you have to build what people will buy now.  If you don't you won't have the money to research and develop what people will want in the future.  And you better not let on what you seriously plan to build in the future or people won't buy what you are building now.  I've seen more than one company go down the toilet because they announced a break-through product before it was ready for deployment and people stopped buying the current version in anticipation of the new one.   

Back to the original point, do base powerplant efficiencies stay fixed regardless of size?  I would suspect you could get rid of a pretty sizeable amount of the 7-10% transmission/distribution loss if you could put a smaller powerplant closer to the point of use. I know larger cities already do this.  Would it work for me (village of 3,000)?

Keith  

RE: How much loss of energy between power plant and house?

Quote:

Prions, Keith?  Aren't those the proteins that cause mad cow disease?

Absolutely!  That's why I call them that when talking to all my neighbors that own them.   

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

In Vancouver, a good % of the taxis are Prius. Speaking to some of the drivers they love them use half the gas and some are pushing 500,000 km without any serious maintenance issues. If I were driving every day I would seriously consider one. I don't think they could be classed as electric though since all the energy still comes from gas.
Roy

RE: How much loss of energy between power plant and house?

I think we need to stop arguing over how to get the most out of fossil fuels. One day, all the money in the world won't get you a sack of coal or a quart of crude because there just won't be any. This stuff is non-renewable. If we don't act now and start looking at renewable energy soon, our descendants are going to hate us for it. There will be a development gap between fossil fuels and renewable energy when the switchover is made. The sooner we act on the switch, the easier it'll be.

I'm just an idealist, though. When it all gets boiled down, the whole discipline is governed by one single equation:

Efficiency = Desired Output / Cost

That's it. That's all anybody cares about. It's sad but true. I just wish there were more benevolent investors who see the lower returns on alternative energy sources as a public charity.

RE: How much loss of energy between power plant and house?

Back in the day when the handwringers were worrying about human birth rates outpacing horse birth rates which meant that someone was going to have to do without transportation and other handwringers were debating what to do with all the manure that the horses that there were were leaving on city streets, some guy named Henry Ford saw a way to make a buck by producing gasoline driven autos cheaply by utilizing a new concept called the assembly line.

He started with the technology that he had at the time, i.e. he didn't wait until microprocessor ignitions were perfected to start producing Ford Autos.  What he did is viewed with 20/20 hindsight and not from the perspective of what was going on at the time.

But one thing was for sure, it wasn't the horse breeding problem or manure disposal problem that he set out to solve, it was a way to make a buck that he was after.

If someone percieves there is a buck to be made with the technologies that exist today, they will start producing a products that people will buy and 80-100 years from now someone will be writing a post in this forum about what happened in our time that changed the face of technology and industry.

I think I will live long enough to see this evolution occur, be it electric cars or "beam me up" machines.

rmw

RE: How much loss of energy between power plant and house?

Yep, true and good points.  Most people really do think with their wallets.  It's bad, and it's good, as it means you really do know what you need to do to get change.  There isn't a lot of mystery.  Make it cheaper and they will come.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

To answer an earler post, Power plants do have a curve of size vs effecency. And that curve also is driven by techonology.
That explains why 600MW seems good for coal plants, 1000MW seems good for nucular, and 100MW seems good for gas turbins.
There is also a size required and cost factor that enters here. 4.4MW IC plants may be cost effective and quick to install simply because there are so many that roll by with loads of coal (Mass production).

The result is power produced by a mix of plants with different cost factors (effecency also changes with unit load).

And the last factor that effects price of energy is location. Wyoming is a good location for a coal plant because fuel transportation is cheep.

 

RE: How much loss of energy between power plant and house?

So time of use rates and demand control have been addressed. Lets take it to the next level, and treat all those plug in hybrids as a distributed resource the utility can use when needed. The inefficient Otto cycle is already being used to meet demand. Utility starts the hybrids on internal combustion, which feed the grid when demand is high. Please keep the tank full, and see that the exhaust is vented.

RE: How much loss of energy between power plant and house?

So you are thinking that the utilities will send a check to the hybrid owners?

Try this out, in the middle of the night the utility needs your power, and in the morning you have no juce in the battery, and no gas in the car. (Sounds like a teenager in the house).
I just don't think it will fly like that.

How about the utilities buy the 4.4MW diesels, probally cheeper than the accounting with the hybrid owners (One penny for you, one penny for me).

 

RE: How much loss of energy between power plant and house?

You don't really need to run the engine to provide short time peak demand power from the batteries alone.  If the batteries discharge below a certain point, the car can shut itself down.

The utilities are not going to need the power in the middle of the night - they need it for the morning and afternoon/evening peaks.

 

RE: How much loss of energy between power plant and house?

So you run out of gas before you go to bed. That makes it better (Your car engine won't keep you up at night, like your air conditioner).

 

RE: How much loss of energy between power plant and house?

With a full electric you could actually UPS your house.

Keith Cress
kcress - http://www.flaminsystems.com

RE: How much loss of energy between power plant and house?

It would seem very simple to estimate the actual amount of fossil fuels in mpg to run an electric car.
For internal combustion engines - gas vehicles have a conversion of from 20% to 25%. Diesel engines up to 75%.

So if we produce electricity from crude oil we have the initial conversion from burning the fuel which runs the turbins. What is the estimated energy conversion rate? You would have to factor in all costs from pumping water for steam generation to pumping water for cooling. Also the costs of the water itself which is often highly subsidized.

Next we have the energy loss of transmission which I have seen estimated at 5% to 8%.

Next we have the charging of the batteries. I have no idea as to the energy loss at this point but I am sure that it is known.

Finally we have the battery power to the electric motor. What kind of energy loss do we have at this stage? Again I have no idea as to whether the loss at this stage is 5% or 50%.

Efficient electric motors can achieve better than 90% energy conversion.

Just guessing, I would say that diesel is more efficient than electric and electric is likely more efficient than gas.

We also have the recovery of some electrical energy by tapping into braking.

In any case it would seem that we could answer this question by filling in the blanks and doing a little math.

RE: How much loss of energy between power plant and house?

Quote:

Personally I dont think electric vehicles will ever become mainstream.  There is no possible infrastructure that will be capable of supporting them that can be built in the next 15 years and by then Im banking on the hydrogen economy taking over.

Where does the hydrogen come from? No-one touting hydrogen as the way of the future seems willing to actually address this question in a meaningful way.
 

RE: How much loss of energy between power plant and house?

A better question is how to you store hydrogen?
Anyone have an answer for that.
 

RE: How much loss of energy between power plant and house?

Let's find out where the hydrogen is going to come from first; then we can worry about storing it.

rmw

RE: How much loss of energy between power plant and house?

I often work on a prototype skid that strips Hydrogen from natural gas and water. There's no reason to store large quantities if you can tie into a gas line and produce it locally.
Roy

RE: How much loss of energy between power plant and house?

roydm - How efficient is your process? How much electricity is required?

RE: How much loss of energy between power plant and house?

Quote:

I often work on a prototype skid that strips Hydrogen from natural gas and water.

Natural gas isn't a renewable energy source. Wouldn't it be better to use the natural gas directly instead of converting to hydrogen and adding more losses?
 

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