Does nuclear power cost massive billion gov subsidies?

In summary, the article claims that nuclear power is not economically competitive and can only be built with heavy government subsidies. The private sector recognizes that without these subsidies, nuclear power would not be cost-competitive. Wall Street has also rejected nuclear power in favor of more affordable green energies like wind and solar. The future of new reactor construction relies heavily on federal and state subsidies, which could potentially leave taxpayers with a significant liability. However, the cost comparison between nuclear and other forms of energy does not take into account these subsidies. The main issue is that green energy cannot currently meet the demand for electricity, making nuclear power and coal the only viable options for the bulk of the market. The cost per wattage of nuclear power is comparable to coal, but
  • #71
Morbius said:
Xnn,

Yes - that's Al Gore's old saw. However, when you have large demands - then you can build large
plants. For example, the Chicago / Northern Illinois area serviced by Commonwealth Edison uses
about 7 reactors. These are the "XXXL" size and you still need 7 of them to provide the power for
Chicago and its suburbs.

So what's the problem?
The problem is that the cost of financing one reactor can be more than the gross revenues of a power utility, thus too much concentrated risk in one pie. See e.g. Duke Energy - revenues ~$3.1B. If the Cherokee two reactor site they have proposed costs the same as the dual AP1000's proposed for Levy, Fla, that's $14B, 4x the annual revenue of the company.
 
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  • #72
I agree with mheslep; Too Big = Too much Risk.

There is too much risk of cost over runs and it's too difficult to contain the risk.

This is why Nuclear Power Construction really needs to be a Government job or at least the Government needs to shoulder some of the risk.

Many years ago, I worked at a plant under construction and frankly it was something of a joke. Every few months a new estimate of when we'd be done would come out. And of course the cost only went up over time. This was at a regulated Utility and the contracts were all basically cost plus. So, there was lots of money to be made, but the economics were basically an unknown. I had the sense that the only reason we ever finished was that nobody wanted to waste all the effort that had been expended to date.

Going forward, we (the USA) really need to concentrate on just 1 or 2 designs. Ideally, they'd be ones that are already constructed, but unfortuantely what is being planned are all "new", "advanced" or some other variation. So, it's a big unknown as to how expensive it they will really be.

Of course, Nuclear construction is a great way to keep unemployment down!
 
  • #73
mheslep said:
The problem is that the cost of financing one reactor can be more than the gross revenues of a power utility, thus too much concentrated risk in one pie. See e.g. Duke Energy - revenues ~$3.1B. If the Cherokee two reactor site they have proposed costs the same as the dual AP1000's proposed for Levy, Fla, that's $14B, 4x the annual revenue of the company.
mheslep,

OH BROTHER - and I suppose the cost of your home is LESS than your yearly income!

What a total contrivance! Utilities have ALWAYS built plants with a costs more than their revenues.

The question that one needs to ask is whether the amount of electricity generated by the plant is enough
to cover the interest and principal payments on the loan the utility gets to finance the construction.

The answer to that is YES - or nuclear utilities wouldn't be making any money.

The ONLY concern about the capacity of the plant is that the utility has to be able to shutdown the plant
for refueling and still meet the demands of its customers. Coal power plants tend to be about the same
size as the nuclear power plants - and they too need to be shutdown for maintenance on the turbines on
a regular basis. [ Turbine maintenance in nuclear power plants is done during refueling outages ]

For example, we will take Commonwealth Edison with 7 reactors in its fleet. Now the total capacity of
the CommEd fleet is sized to meet the peak demands during summer - with air conditioning loads. The
demand in Spring and / or Fall is less - MORE than 14% less. Therefore, CommEd can afford to shutdown
one of the nukes and still meet its demand. If a utility had a total capacity of 1300 Mw(e) of which 1000 Mw(e)
was a single nuclear power plant - then such a utility has no business buying a nuclear plant. A plant of
1000 Mw(e) out of 1300 Mw(e) is too many eggs in one basket. But CommEd has no problem with a single
reactor being 14% of the fleet capacity. Likewise, in northern California, PG&E gets about 25% of its capacity
from the 2-unit Diablo Canyon plant - so each reactor represents 12.5% of PG&E's capacity. That's not a
problem - and most large utilities have no problem having over 1000 Mw(e) represented by a single plant.

This "too big" argument is a total "red herring".


Dr. Gregory Greenman
Physicist
 
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  • #74
Xnn said:
There is too much risk of cost over runs and it's too difficult to contain the risk.
Xnn,

Most of the delays to nuclear power plants were caused by lawsuits. What the USA needs to do
it get rid of the two step licensing scheme.

When a utility proposes a plant and applies for a construction permit - THEN you can have all the
lawsuits to decide if / how the plant should be built.

However, once the Courts have ruled - and the NRC has approved a construction permit - then there
should be NO MORE LAWSUITS! The Courts have spoken. The NRC should oversee the
construction of the plant, and if it is built according to the construction permit - then the utility gets a
license to operate the plant. This would be just like a building inspector issuing a certification of
habitability for a recently completed house.

Instead, the USA had a system in which once the plant was built and the utility had to pay on a loan;
we allowed more lawsuits to question whether the plant should have been built. We also allowed a
State organization like the New York state PUC to set a cost of $0.00 for the cost of electricity
generated by the plant as in the case of Shoreham.

Congress should amend our laws to prohibit this type of "second guessing". We make a decision to
build / operate the plant - OK'ed by the Courts and State - and then those decisions can not be
reversed.

Dr. Gregory Greenman
Physicist
 
  • #75
Morbius said:
mheslep,

OH BROTHER - and I suppose the cost of your home is LESS than your yearly income!

What a total contrivance! Utilities have ALWAYS built plants with a costs more than their revenues.
Please name one energy project in the past 30 years for which the total project cost exceeds 4x annual revenues of a utility buying the project.

The question that one needs to ask is whether the amount of electricity generated by the plant is enough
to cover the interest and principal payments on the loan the utility gets to finance the construction.

The answer to that is YES - or nuclear utilities wouldn't be making any money.
Amusing.
Businesses, unlike a home buyer, are generally wary of committing the entire resources of an enterprise because of the risks involved. The business must make a prediction of growth of demand, in this case electrical, in the market. What if there's a big outlier drop-off in demand growth, say caused by a severe recession like we're experiencing now? What if there are major flaws in the construction phase caused by faulty materials used by the contractor, causing major rework delays as there were in Olkiluoto?

Why can't you be bothered to actually look anything up? You'll find numerous statements along these lines from utility CEOs and bond rating agencies like Moody's.
 
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  • #76
mheslep said:
P
Why can't you be bothered to actually look anything up? You'll find numerous statements along these lines from utility CEOs and bond rating agencies like Moody's.
mheslep,

YOU are the one that needs to look things up! How do you "think" that Commonwealth Edison
was able to build 10 nuclear power reactors over the last few decades?

Sure - some utilities are smaller and can't utilize a nuclear power plant in their fleet because the
size is too big. Sure - some utilities have CEO's that are more conservative.

However, there are utilities / CEOs that have been able to finance and afford nuclear power units
in their fleet of power plants - which is why the USA currently has 104 operating nuclear power plants.

What's your point? Is it that we should forgo building nuclear power plants because they are "too big"?

That's the type of brainless comment I expect from Al Gore - but not somebody that posts here.

We have 104 OPERATING nuclear power plants in the USA - so they are NOT "too big".

Dr. Gregory Greenman
Physicist
 
  • #77
mheslep said:
What if there are major flaws in the construction phase caused by faulty materials used by the contractor, causing major rework delays as there were in Olkiluoto?
mheslep,

You mean "What if the utility doesn't do it job of oversight on the project?"

If the utility hires a poor contractor and / or the utility and contractor are not doing their job of making
sure that they are not purchasing faulty materials - then there can be delays - as with a FOSSIL plant
too. If the materials in a coal-fired boiler don't meet the ASME codes - that causes delays too.

Why would you assume that this is a problem unique to construction of nuclear power plants?

It is also a problem that can be readily avoided by proper oversight by the utility and by hiring a
contractor that knows how to build a nuclear power plant.

If a utility attempts to build a nuclear power plant "on the cheap" - then they are going to find that it
costs them more money in the long run.

However, there are many nuclear power plants - like those in the CommEd system where your
hypothetical problems were avoided by good oversight and construction practices.

It's not like nobody has built a nuclear power plant before, so that there are unknown problems.
The lab I work at built a major facility that ran over budget because it was the first of its type. But
we're not talking about that in the case of a nuclear power plant.

Dr. Gregory Greenman
Physicist
 
  • #78
I'm not so sure that "too expensive" is a red herring. I hear this mentioned by the utilities, and already two utilities have backed away from plans on new plants.

Utilities are skittish, especially given the financial situation. I imagine Wall Street will be skeptical about new plants.

The last reactors completed were started in the late 70's and things have changed a lot since then.


Shoreham is a bizarre case. Firstly, like others build last, it was way over budget due to lawsuits (intervenors), but also because of engineering problems and retrofits. Then it was not allowed to operate and as previously pointed out, it was 'taken over' by the state, which paid $1 and allowed the utility to raise rates.

Cost is a big issue at utilities, which have cut staff to the bone.
 
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  • #79
Astronuc said:
I'm not so sure that "too expensive" is a red herring. I hear this mentioned by the utilities, and already two utilities have backed away from plans on new plants.
Astronuc,

I'm sure some CEOs are ultra-conservative when it comes to a nuclear power project.

However, I think "too expensive" is mixed in with the uncertainty of the political situation.

I bet one could plot how much money the utilities are willing to risk as a function of the
uncertainty of having the investment pan out. Because of our current licensing system,
as well as the fact that a utility's plans can be essentially "vetoed" in the latter stages
by State regulators - as happened at Shoreham - then I completely understand the
unwillingness of utility CEOs in this matter.

However, rather than foregoing nuclear power, or doing nuclear power "on the cheap" - we need
to address the uncertainties. We need to be able to assure a utility that once they have won their
case in Court - that a subsequent lawsuit can't overturn the previous win. [ In other legal cases,
the legal profession has the concept of a "second bite at the apple" - which means to redo the
adjudication of a resolved legal issue. "Second bites" are usually not permitted - except when it
comes to nuclear power plants. ]

We have to ensure that State PUCs don't "abuse" their power by dictating that a utility has to
give away power for free if it is generated by a nuclear power plant as New York did with Shoreham.

If we did that - I bet a lot of this "too expensive" talk would go away. Even under current conditions,
there are some utilities that are willing to build more nuclear power plants.

For example, Detroit Edison in Michigan realizes that the long term view for their service area with all
its industry; will require more electric power generation capacity - and Detroit Edison has announced
its intent to build Fermi Unit 3 to join the currently operating Fermi Unit 2.

For those utilities that are willing to commit to building more nuclear capacity - we should help enable
them to do so.

It's not useful for us to say "they're too expensive - let's not build nuclear power plants".

That's just throwing in the towel for no good reason.

Dr. Gregory Greenman
Physicist
 
  • #80
Morbius said:
...Why would you assume that this is a problem unique to construction of nuclear power plants?
I have not assumed that, said nothing of the kind. Please don't attribute to me that which I did not say.
 
  • #81
Morbius said:
What's your point? Is it that we should forgo building nuclear power plants because they are "too big"?

That's the type of brainless comment I expect from Al Gore - but not somebody that posts here.

We have 104 OPERATING nuclear power plants in the USA - so they are NOT "too big".
"Big" is a problem for regions with low populations/density. It is certainly a problem for Saskatchewan, whose government is encouraging the development of nuclear power in the province. The province has 1 million people in an area (651,000 km^2) almost the size of Texas. Total electrical consumption is 3,000 MW. The electrical grid is designed around small power plants distributed around the province.

The proposal is to build two 1000 MWe nuclear plants. There is an enormous cost in creating the electrical grid to distribute that much power from one location throughout the province or for export to other jurisdictions.

AM
 
  • #82
I think we all agree about the political issues associated with nuclear power, and even big power plants. Not only do some folks not want nuclear (but some certainly do), but some don't want transmission lines.

Utilites are run by businessmen who are averse to risk. Big costs mean big risks, which is why utilities have expected some funding (including loan guarantees) from the US government before they commit to new nuclear power plants.

There are numerous sites around the country that can accommodate one or more units. These sites were designed for 2, 3, or 4 and even up to 5 units (e.g. Palo Verde). The problems with TMI and the fire at Browns Ferry really put a damper on new plants for the last three decades. The industry hopes that the successes since then will help pave the way for new plants.

Still we have to determine a solution to the accumulated spent fuel. That's also a political problem, and it doesn't help that we seem to change directions with each new administration or congress.
 
  • #83
Astronuc said:
Still we have to determine a solution to the accumulated spent fuel. That's also a political problem, and it doesn't help that we seem to change directions with each new administration or congress.
It is also a technological problem. One best solution is to use it. That solution would require reactors that, with secure reprocessing, will use all the energy in the fuel (Uranium or Thorium) and dispose of fission products after they have cooled off (in a hundred years). We are at least 25 years away from such technology. In my view it would be a mistake to accede to political pressure to do something now with spent fuel that would render the fuel unusable in the future. That is one sure way to create a storage problem lasting eons.

AM
 
  • #84
Andrew Mason said:
It is also a technological problem. One best solution is to use it. That solution would require reactors that, with secure reprocessing, will use all the energy in the fuel (Uranium or Thorium) and dispose of fission products after they have cooled off (in a hundred years). We are at least 25 years away from such technology. In my view it would be a mistake to accede to political pressure to do something now with spent fuel that would render the fuel unusable in the future. That is one sure way to create a storage problem lasting eons.
Andrew,

If you reprocess / recycle spent nuclear fuel - the longest lived radioisotope in the waste stream will
be Cesium-137 with a half-life of just 30 years.

The problem won't last eons because the radioactivity won't.

Additionally, if one converted the fuel to some other form, borosilicate glass, for example; and it was
determined another form was better - the conversion is NOT irreversible.

The WORST thing is probably to do nothing.

Dr. Gregory Greenman
Physicist
 
  • #85
mheslep said:
I have not assumed that, said nothing of the kind. Please don't attribute to me that which I did not say.
mheslep,

If you use that argument as an argument against nuclear power - then you ARE assuming that
some other form doesn't have the problem.

If ALL the options have the same problem; then there's no reason to bring it up.

I will attribute to you an line of reasoning that you don't understand that you are making.

Dr. Gregory Greenman
Physicist
 
  • #86
In order to justify construction of a multi-billion $ nuclear plant the potential payback needs to outweigh the risk.

A year ago, it looked like oil was going thru the roof and the price of all energy forms were following. This made future Nuclear look much more promising than it does now.
 
  • #87
Morbius said:
mheslep,

If you use that argument as an argument against nuclear power - then you ARE assuming that
some other form doesn't have the problem.

If ALL the options have the same problem; then there's no reason to bring it up.

I will attribute to you an line of reasoning that you don't understand that you are making.
All large power projects have greater difficulty getting private funding because of the financial risk to the organization. A failure or large delay in a small project is a loss on the balance sheet. A failure or large delay in project many times the size of the company may mean the end of the company. The 1988 bankruptcy of Seabrook's New Hampshire owner is an example, and there are others. This is one reason small projects, of any kind, are overwhelmingly preferred. Of the 1,522 coal fired power plants in the US, only 12 are over 1000MWe. All of the nuclear proposals currently before the NRC are greater than 1000MWe. The median coal plant size is 100-200MWe. Thus nuclear is at a disadvantage in obtaining financing, not insurmountable perhaps, but none the less a disadvantage.
http://www.sourcewatch.org/index.php?title=Existing_U.S._Coal_Plants
http://www.nrc.gov/reactors/new-reactors/col.html
 
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  • #88
As far I know EDF remains in French Gov Hands.

They own 85% of the shares.
 
  • #89
mheslep said:
The median coal plant size is 100-200MWe. Thus nuclear is at a disadvantage in obtaining financing, not insurmountable perhaps, but none the less a disadvantage.
mheslep,

The only reason the median coal power plant size is so low is that you are counting many older plants.
Most of the more recent coal power plants are in the neighborhood of 1000 Mw(e).

However, there is NOTHING that restricts a nuclear power plant to being over 1000 Mw(e).

If a utility desires a plant with lower power - then they can have one. For example, the
Palisades Nuclear Power Plant south of South Haven, Michigan on the shore of Lake Michigan
is a 730 Mw(e) unit that is comparable in size to many newer coal power plants:

http://www.nrc.gov/info-finder/reactor/pali.html

The reason that utilities are ordering nuclear power plants with capacities >1000 Mw(e) is that
is what the WANT / NEED!

Dr. Gregory Greenman
Physicist
 
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  • #90
Morbius said:
However, there is NOTHING that restricts a nuclear power plant to being over 1000 Mw(e).

Well that's true as far as it goes, but there are a number of costs that scale at less than proportional to the power - and that means that (in crude terms) building and operating two 500 MWe plants is going to cost more than one 1000 MWe plant. To pick a trivial example, the application costs to get a license are not based on the output of the unit. Neither are the payroll costs to run it - that's one big reason you see so many dual units. But the big difference is probably in construction. Take the containment vessel - its volume scales with power; but its construction probably scales closer to its surface area (material cost). That kind of thing pushes the economics to higher power units.

All that said, keep in mind that W designed and licensed the AP600 before they did the AP1000; if you'd really rather have a 600 MWe unit I am sure they would be glad to build one for you.
 
  • #91
gmax137 said:
Well that's true as far as it goes, but there are a number of costs that scale at less than proportional to the power - and that means that (in crude terms) building and operating two 500 MWe plants is going to cost more than one 1000 MWe plant. To pick a trivial example, the application costs to get a license are not based on the output of the unit. Neither are the payroll costs to run it - that's one big reason you see so many dual units. But the big difference is probably in construction. Take the containment vessel - its volume scales with power; but its construction probably scales closer to its surface area (material cost). That kind of thing pushes the economics to higher power units.

All that said, keep in mind that W designed and licensed the AP600 before they did the AP1000; if you'd really rather have a 600 MWe unit I am sure they would be glad to build one for you.
gmax,

Yes - I'm WELL AWARE of the scaling of costs - I've had to do that PROFESSIONALLY!

That's just one of the things that goes into the decision as to plant size. If you want the cheapest
operating costs per megawatt - then you go with a large plant. However, the down size to that is
that you have "a lot of eggs in one basket".

One the other hand, if the utility doesn't want so many eggs in one basket - they can opt for more
flexibility by having multiple smaller plants. However, as you correctly point out; you pay for that
flexibility in increased cost per megawatt.

It's a choice for the utility. However, too many say that a nuclear power plant HAS to be large. It's
like Al Gore's comment that "nuclear power plants only come in one size - extra large". NO they don't.
Utilities CHOOSE the large plants because of the lower cost and they NEED the capacity.

But if a utility would rather have more flexibility for more money - they certainly can be accommodated.

Dr. Gregory Greenman
Physicist
 
  • #92
Morbius said:
...Utilities CHOOSE the large plants because of the lower cost and they NEED the capacity...
Linking capacity and demand to largeness doesn't follow, as the same demand could be met with more and smaller plants.
 
  • #93
mheslep said:
Linking capacity and demand to largeness doesn't follow, as the same demand could be met with more and smaller plants.
mheslep,

GADS - this is like pulling teeth.

The utilities that order large plants are the ones that have a large demand, AND opt for the
lower cost per megawatt of the larger plant as opposed to having smaller plants.

As gmax137 very correctly explains there are fixed costs that don't scale with the size of the
plant. Therefore, one gets a lower cost per megawatt for the larger plant.

That is what most utilities are opting for - they want the lower cost per megawatt of the larger
plant - and hence CHOOSE not to meet the demand with multiple smaller plants.

If the utility wants some more flexibility; they can get smaller plants - but it does cost them.

When a utility is ordering a large plant - it means they have both the demand for that capacity;
AND they choose to opt for the lower cost per megawatt of the larger plants.

Dr. Gregory Greenman
Physicist
 
  • #94
For nuclear plants, yes the twenty filings with the NRC are all large. As for all general types of power plants like coal, EIA records show power providers opt for much smaller plants. See attached figure - 42 US plants, with coal as the primary power source, brought on-line in the ten years 1995 to 2005. Total nameplate capacity: 6321MWe, average plant size 152 MWe, median 82 MWe, largest 591 MWe, smallest 0.4MWe. The size is lower still for recent gas fired plants.
Source:
http://www.eia.doe.gov/cneaf/electricity/page/capacity/existingunits2005.xls
 

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  • #95
It is important to note, though, mheslep, that most of the plants on that list under 100 mW are not owned by power companies but by industry and institutions. If you remove those, the median is much larger. That's probably still not the best way to cut the data though, as those above the median have a significantly larger total capacity than those below. A better way would be to find the point at which those above have the same capacity as those below.*

No, large plants aren't feasible everywhere or for every company. It does require a large market and high growth. But IMO, that's a flaw in the structure of the energy industry that needs to be dealt with via regulation. Energy would be cheaper if the government encouraged/helped companies take advantage of economies of scale.

[edit] *When I sliced the data, I found 38 plants with a total capacity of 5096 MW. Not sure the reason for the difference. In any case, the largest 5 have a capacity equal to the smaller 33 and the cutoff is between 329 and 395 MW. Ie, even without cutting off the non-utility plants, most of our generating capacity is in plants 395 MW and greater.

In other words, electric companies typically opt for plants of 395 MW and larger rather than multiple smaller plants of equal capacity to satisfy their capacity needs.
 
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  • #96
russ_watters said:
It is important to note, though, mheslep, that most of the plants on that list under 100 mW are not owned by power companies but by industry and institutions. If you remove those, the median is much larger.
<shrug> Their Watts are as good as anyone's. Even the so called 'power companies' are into multiple games. Duke Energy does telecom, real estate, etc.
That's probably still not the best way to cut the data though, as those above the median have a significantly larger total capacity than those below. A better way would be to find the point at which those above have the same capacity as those below.*
Good point, I started to slice by 100MW increments but ran out of time.

No, large plants aren't feasible everywhere or for every company. It does require a large market and high growth. But IMO, that's a flaw in the structure of the energy industry that needs to be dealt with via regulation. Energy would be cheaper if the government encouraged/helped companies take advantage of economies of scale.

Edit: Regards economies of scale, I'm reminded of another driver - cogeneration of electric power and facility heating. Some of these cogeneration gas electric and heat plants reach very high system efficiencies, 70-80%. It is difficult to see how a distant electric-only plant even 50x larger could compete economically with a local cogeneration facility.
[edit] *When I sliced the data, I found 38 plants with a total capacity of 5096 MW. Not sure the reason for the difference.
Hm. 42 in the snapshot I attached. I used five different types of coal: BIT, LIG, SUB, WC, SC (2nd tab in the spread sheet)

In any case, the largest 5 have a capacity equal to the smaller 33 and the cutoff is between 329 and 395 MW. Ie, even without cutting off the non-utility plants, most of our generating capacity is in plants 395 MW and greater.

In other words, electric companies typically opt for plants of 395 MW and larger rather than multiple smaller plants of equal capacity to satisfy their capacity needs.
Apparently, though IIRC the power companies increasingly take stakes in these smaller operations - at least the construction end.
 
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  • #97
I guess each technology has its preferred scale. Former nuclear power plants were more around 300 MW, but, as has been pointed out, nuclear plants are typically things which win in economy of scale until something of the scale of 1 GW. Note that you don't see 10 GW plants either (yet ?). Maybe coal power plants are somewhat smaller because you get logistics problems (just a wild guess on my side) ? And gas plants because turbines are not practical beyond a certain size ?
Wind turbines also come in typical sizes of a few MW.

I guess that the question is: if there were a size-independent power tech, what would be the size of the preferred unit by utilities ?

There have been designs for smaller nuclear power plants like the 4S of Toshiba (on which a hoax is based of your private nuke in your basement), which taps more in the 10 MW range. So all this is possible (at least on paper).
 
  • #98
vanesch said:
I guess that the question is: if there were a size-independent power tech, what would be the size of the preferred unit by utilities?
If plant cost-efficiency were size-independent, they would almost put one at each consumer's meter to cut transmission losses. If each person uses 1KW (and current nuclear plants are good for the base 50%) then at least 1GW could be built for every city with population above two million, but there might be trouble whenever that fraction of the local supply all goes down for maintenance..
 
  • #99
mheslep said:
Edit: Regards economies of scale, I'm reminded of another driver - cogeneration of electric power and facility heating. Some of these cogeneration gas electric and heat plants reach very high system efficiencies, 70-80%. It is difficult to see how a distant electric-only plant even 50x larger could compete economically with a local cogeneration facility.
mheslep,

By quoting an efficiency of 70-80%; you are lumping heat and electric energy together.

Thermodynamically; that is really DISHONEST - because it ignores the fact that electricity
is a high quality / zero entropy form of energy - while heat is a lower quality and non-zero
entropy form of energy.

I would refrain from lumping these two dissimilar quantities in a single metric.

Dr. Gregory Greenman
Physicist
 
  • #100
Well I guess one man's rejected waste heat makes another man's office warm and cozy.
 
  • #101
because it ignores the fact that electricity
is a high quality / zero entropy form of energy

Isn't this dishonest? Electricity is far from zero entropy, although it does generate much less than most other forms of power transmission. If your end product is going to be energy in the form of heat anyway, then why is co-generation dishonest?
 
  • #102
Morbius said:
Thermodynamically; that is really DISHONEST - because it ignores the fact that electricity
is a high quality / zero entropy form of energy - while heat is a lower quality and non-zero
entropy form of energy.
I thought mheslep made a good point. We are talking about thermal energy, not electricity. Nuclear and fossil fuels produce heat. If the goal is to produce energy that saves CO2 emissions and reduces fossil fuel consumption, co-generation can provide a solution.

Consider this scenario where a community that needs 1000MW of heat and 500 MW of electricity. If fossil fuels are used to meet this need, a total of 2500MW of fossil fueled heat is needed. If co-generation is used, I build a 500 MWe fossil fuel plant that uses 1500 MW of heat and I use the waste heat for heating. I save 1000 MW of fossil fuel.

If I build a 500 MWe nuclear plant I have to continue burning 1000 MW of fossil fuel. So I end up saving 1500 MW of fossil fuel, or only 500 MW more than the co-generation model. So a 500 MWe nuclear plant only saves 500 MW of fossil fuel (ie. 500 MW more than the co-generation model).

AM
 
  • #103
I've always been interested in knowing whether a good use of nuclear might be to throw up a 4000MW thermal only plant in the Rockies in the midst of one of those colossal shale oil deposits, then most all of that thermal energy could be used to separate out the oil, instead of rejecting 60-70% up the cooling tower.
 
  • #104
What is the cost of nuclear disposal with respect to economies of scale? I think everyone has acknowledged that in the future our transportation will no longer be powered by fossil fuels and that energy will have to come from the stationary power infrastructure. Just using some very rough hand calculations and some numbers from 2004 I calculated the US uses about 8 trillion kWh's of energy to power our cars, trucks, and airplanes for an entire year. Assuming nuclear power takes on this load along with the load from station fossil fuel power, would the cost of waste per kg decrease by sharing fixed costs or would it increase similarly to economies of scale of precious materials?
 
  • #105
More EIA plant size slicing:
Attached pie chart for all ~16000 US power sources, of all types, broken out in 100MW increments.

Here's the associated breakout numbers in GW, (100MW increments)
0-100MW: 248.2GW, 23.3%
<200: 240.9, 22.6%
<300: 118.3, 11.1%
<400: 66.4, 6.2%
<500: 50.6, 4.7%
<600: 69.4, 6.5%
<700: 63.1, 5.9%
<800: 38.8, 3.6%
<900: 61.0, 5.7%
<1000: 29.9, 2.8%
<1100: 5.2, 0.5%
<1200: 25.5, 2.4%
<1300: 44.2, 4.1%
<1400: 5.6, 0.5%
Total US nameplate capacity 1067GW
 

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