[jimk]

Here's a nice picture to see how liquid fuels fit into U.S. energy usage:

http://eed.llnl.gov/flow/02flow.php

Of course this doesn't show how transportation fits into the economy.

[Starvid]

$this->bbcode_second_pass_quote('Novus', 'J')ames Schlesinger is right to a point that peak oil is only a liquid fuels crisis. The problem is that so much of our world is dependent on liquid fuels that Peak oil is going to be a huge disaster. The prevailing economic theory of our time is Global Capitalism and it is entirely dependent on cheap and abundent liquid fuels. Locally our economies are almost entirely liquid fuel dependent. Suburbia will be completely untenable in the face peak oil.

Putting things in perspective, if we were to switch over to power our cars and trucks with nuclear electricty every suburban neighborehood would need it's own nuclear power plant. If cars were to be powered by wind every car would need to come with a 200 foot wind mill to put in your back yard. If cars were powered by solar you would need four acres of solar panals to fit in your back yard. The alternatives just arn't scaleable the way oil is or was.

In 1920 there were inter-urbarn street car lines that went from Boston to Washington DC and from Pittsburg to Chicago. Along the street car lines were strings of small towns surounded by farmland that could grow most of the their own food. If they were still operational peak oil would not be much of a problem. Instead we live in a world warped by the pervese visions of GM and Wal-Mart.

[Starvid]

$this->bbcode_second_pass_quote('backstop', 'S')tarvid -

From the point of view of sustainable agriculture,

on which your (somewhat optimistic ?) vision of globally peaceful Nuclear-powered Industrial Welfare States would of course be dependent,

I'd say that Peak Oil is one of a range of common symptoms of a defunct isolationist ideology
that seeks to centrailize wealth, power, production and politics -

[dub_scratch]

$this->bbcode_second_pass_quote('Starvid', '.')...an electric car has an efficiency of roughly 75 %

[rogerhb]

$this->bbcode_second_pass_quote('Starvid', 'I') like Industry and Corporations

Without those two things (among many others) we would live in preindustrial poverty. That is not something I am at all interested in.

[EnergySpin]

$this->bbcode_second_pass_quote('dub_scratch', '
')
Electricity does not have much of an efficiency advantage over petroleum and it has quite a large disadvantage as a means of a transportation energy form. .

[dub_scratch]

$this->bbcode_second_pass_quote('EnergySpin', '
')Dub we know you hate all cars ... but you are wrong on this one.
Starvid tried to answer the following question: how much does the US has to increase generation capacity for an all electric car fleet while you answered the question: how much useful kinetic energy can we get out a given amount of coal/uranium/dams etc.
These are two different questions .... with different answers.
In any case, an all electric public transportation sector AND high density urban planning is the sane solution out of the US peakoil situation.

[Novus]

Starvid, I think the premise for you calculations are a bit off. The 20% mirror cannot be applied when saying nuclear is going to replace petroleum. We need a 100% solution not a 20% solution. Bottom line is if nuclear is going to save suburbia it would have to increase from 8.1 quads today taking on an additional 26.5 quads to cover transportation for a total of 34.6 quads. In the simplistic model we are talking a four fold increase here.

In the more complex model you have to look at efficiency of the electric grid to calculate how much loss is going to come from the double step conversion penalty of Nuke -> Electricity -> Transportation. The petroleum -> Transportation single step conversion is much more efficient.

If the present electical system produces 38.2 quads but 26.3 quads of that is wasted in distribution you have to carry that waste ratio over to the imput side of transportation arrow. Our 8.1 quads of nuclear input after being distributed as electricity only ammounts to 2.5 quads. Therefore we would need to increase our electrical output from 2.5 quads today taking on the additional 26.5 quads for transportation for a total of 29 quads. That is and increase by a factor of 11 or 12.

If 90% of the population of America lives within 50 miles of a nuclear power plant then if the planned increase were to take effect 90% would be living within 4 or 5 miles of a nuclear reactor. My original statement stands: "A nuclear power plant in every neighborehood."

[Geko45]

$this->bbcode_second_pass_quote('Starvid', 'N')ot energy crisis but a liquid fuel crisis!

[EnergySpin]

$this->bbcode_second_pass_quote('dub_scratch', '
')Energyspin, please note that I did not try to dispute starvid's simple equation of how much electricity (mostly from dirty coal plants or costly nuke plants) it will take to power the National Traffic Jam. My attempt was to debunk the myth of the thermodynamicly efficient EV. I don't have a problem with starvid's numbers, but the only thing maybe needs to be addressed is what factor would replacing natural gas electricity generation add to the deficit. My position would be that we are going to have to build nuke plants for electricity but it ain't gonna be for the use of electrified traffic jams.

[Starvid]

$this->bbcode_second_pass_quote('Novus', 'S')tarvid, I think the premise for you calculations are a bit off. The 20% mirror cannot be applied when saying nuclear is going to replace petroleum. We need a 100% solution not a 20% solution. Bottom line is if nuclear is going to save suburbia it would have to increase from 8.1 quads today taking on an additional 26.5 quads to cover transportation for a total of 34.6 quads. In the simplistic model we are talking a four fold increase here.

[dub_scratch]

$this->bbcode_second_pass_quote('Starvid', '
')
But some places (like the countryside) will always need cars. Mass transit becomes just too expensive. My basic idea is that if you live in a city (including suburbs) you shouldn't need a car. If you don't live in a city the car is something you'll need owning.

[Novus]

$this->bbcode_second_pass_quote('Starvid', '
')Well, no. Transportation doesn't need 26,5 quads of energy. It needs 5,3 quads.

[Starvid]

You fail to understand the calculations. Using nuclear energy for transportation is a two step process, that is true. But is already inlcuded in my calcualtions.

In a ICE car there is only one energy transformation, petroleum-> propulsion. The efficiency of this process is roughly 20 % (5,3/26,5=0,2).

In an electric car it is a two step process. First we have the efficiency of the car itself, which is 75 %. This means we need 5,3/0,75=7,06 quads of electricity to power these cars.

If you look at the energy flow diagram you see that today the US uses 11,6 quads of electricity, so the increase is (11,6+7,1)/11,6=1,60, roughly 60 %. If one does the calculation more carefully (as I did above) the result is +50 %.

If we use steam plants (coal, oil, gas, biofuels, nuclear) to make these new 7,1 quads of electricity we will likely need about three times as much energy as steam plants have an efficiency of roughly 1/3. 7,1*3=21,3 quads.

If we look at the primary energy used to make electricity today we see it is 38,2 quads. (38,2+21,3)/38,2= +56 %.

So here we are again with that number, which is the correct one.


So, the efficency for using nuclear energy for tranportation is not 6,2 %. It is 0,33*0,75= 25 %.

$this->bbcode_second_pass_quote('dub_scratch', 'P')etroleum has an efficiency of 5.3/26.5= 20%

Electricity is 11.9/38.2= 31%

The total cycle from energy source to EV is (11.9/38.2)* 75%= 23%

[Novus]

$this->bbcode_second_pass_quote('Starvid', '
')In a ICE car there is only one energy transformation, petroleum-> propulsion. The efficiency of this process is roughly 20 % (5,3/26,5=0,2).

[Starvid]

Well, since you are the one with faulty mathematics and refrain from understanding even basic math and a basic graph I now understand why doomers are doomers.

It would be nice if other users commented on the mathematics issue. I might warn you that you will be outnumbered everyone-to-one.

[dub_scratch]

$this->bbcode_second_pass_quote('Novus', '')$this->bbcode_second_pass_quote('Starvid', '
')In a ICE car there is only one energy transformation, petroleum-> propulsion. The efficiency of this process is roughly 20 % (5,3/26,5=0,2).

[jimk]

That chart with energy flows is a bit confusing.

The break-down into userful energy and lost energy is really wierd. Probably there are some notes at the web site that explain it. But really all the energy flow ends up being lost at some point.

My guess is that they are counting "useful energy" of transportation to be power delivered from engine/motor to the transmission. So the losses in the engine are "lost energy" while the friction from air & tire resistance and from braking, all that is "useful energy". Just guessing, but what else could it mean. Sure there is real energy gained hauling a load up a hill, but it all dissipates going down the other side.

I have no idea what they mean by useful versus lost energy in residential/commercial. If I heat my house, is that useful energy or lost energy? Probably useful. So what is lost energy? I have no idea how gas powered air conditioners work, but maybe there is an engine in there somewhere, so there is some power transfer point in an air conditioner & energy lost on one side is counted as "lost" and on the other side is "useful".

Seems clear enough how the accounting ought to work for energy content of e.g. coal. One assumes some kind of perfect combustion and just figures the total energy put out.

With nuclear fuel, that gets a lot stranger. A radioactive isotope will have some chain of decay, or maybe a tree of possible decay paths. Each decay will result probably in some gamma radiation as well as some kinetic energy lost. What gets really wierd is that e.g. an emitted neutron could convert e.g. U-238 to Pu-239. So how should that be tabulated in the amount of energy contained in the nuclear fuel? Very tricky business. It may well be that the number given just assumes no fuel reprocessing and the level of energy capture typical in a reactor. I.e. some energy loss has already been counted out before the total is accumulated. Presumably what is tabulated is the energy captured by the water that is heated up. Only some of this energy gets turned into electricity.

I think "distributed electricity" means power at the customer's site. So the "electrical system losses" includes both what's lost at the power plant, turning fuel into steam into electricity, plus what's lost on transmission lines etc.

It's a pretty chart, but the more one studies it, the more it becomes clear that the beauty is skin deep. Lots of critical details are swept under the rug!

[UIUCstudent01]

$this->bbcode_second_pass_quote('Starvid', 'I')t would be nice if other users commented on the mathematics issue. I might warn you that you will be outnumbered evyone-to-one.

[Novus]

Here is where I get my numbers.



Overall using nuclear power to fuel transportation is two step problem of waste. Nuke -> Electricity -> Transporation

You must calculate the coefficients of waste for each conversion and then multiply the coefficient together to find the total waste ratio. Overall it takes 16 quads of nuclear power to get one quad of usefull transportation energy. The total process is only 6.2% efficient. We need (16*5.3) = 84 quads to get the 5.3 quads of usefull transport energy the country needs. This translates into a 1000%+ increase in nuclear power generation on top of the power we already use.