Best type of energy? Nuclear, coal, etc?

Science & Technology Engineering & Technology
1

For my thermodynamics class my professor (who has environmental tendencies) is having us write a short paper about (alternative) energy sources. What would you argue should be the primary energy source to power the country/globe?

I think coal currently powers over half of the power grid, so I wouldn’t be surprised if it was economically the best option. Right now, I’m listed to write about nuclear energy. Any thoughts about these or others?

If the utility of certain resources is downplayed due to things like green house gas emissions, which aren’t all that bad, then that would be a good angle for me to argue for the use of a resource, whilst simultaneously presenting a case against the global warming scare (which is being force-fed to us in my engineering program now and again).

Thanks

2

What would you argue should be the primary energy source to power the country/globe?

Atomic Static Electricity from a miracle motor! (or something like that)

3

If the energy market were unregulated, it would be easy to know - because the best would be dominant. Unfortunately, it is very heavily regulated so I don’t know if nuclear is second to coal because it is more expensive or simply because the regulations make it so.

I can tell you that the “alternates” - solar, wind, etc - are crap.

4

Do I remember correctly that there have not been any nuclear power plants built for like 30 years? (I mean in the U.S.)

What about Geothermal? I thought that was okay as far as it goes (but I don’t know much about this stuff).

Edit: answered my first question on wiki http://en.wikipedia.org/wiki/Nuclear_power

As of 2007, Watts Bar 1, which came on-line in Feb. 7, 1996, was the last U.S. commercial nuclear reactor to go on-line. This is often quoted as evidence of a successful worldwide campaign for nuclear power phase-out.

5

What would you argue should be the primary energy source to power the country/globe?

That is a stunningly invalid question. Hydro is neat – if you can get it. Imagine a world-wide law requiring all electricity to be hydo – lights go out in Chad, most of the US, the UK etc. Okay, coal. Wait, coal isn’t actually universally available for free, so in some cases natural gas is better. Nuclear is a good choice, except that I would not be so thrilled with Chad having nuclear power plants, simply because they don’t have enough well-traind nuclear engineers. Solar is actually not so bad in the middle of the Khalahari desert, in that it beats having no electricity at all. Local diesel generators provide all of the electric power of Ukerewe island (because that’s the best they can manage).

The idea that there has to be a single global answer is just so strange. The answer is “whatever is most profitable, in the long term”. That’s an economic question, not an engineering one. Obviously, you gotta consult an engineer to discover that “biofuel” power plants are like pounding money down a rathole, in case it didn’t occur to you that ethanol does not literally grow on trees, even it it can be made from trees.

6

There isn’t one “best” source of energy; you are right that it depends largely on economics, and what is economically most efficient today may not be in the future, due in large part to technological developments.

But since you say you’ve been slated to write about nuclear power, you should be sure to research the new pebble bed reactor design. And read up on Chernobyl and TMI, preferably from a reputable, fact-centered source, so you can rebut spurious safety arguments.

~Q

7

In the US, the NRC issues operating licenses and site licenses. You need a site license to build, and an operating license to operate. Watts Bar 1 got its operating license in 1996 and went online in 1997, but it got its site license in 1972 or 1973. The “30 years” figure refers to site licenses, not to operating licenses. Watts Bar 2 (the second reactor at the site) just recommenced construction last month, under its original '70s site license (each reactor requires its own licenses). While Watts Bar 1 was the last to come online in the US, I do not know if it was the last to receive a site license. I’ll look it up if I get a chance.

~Q

Correction: Watts Bar 1 and 2 share a site license, granted 19 December 1972.

Further update: Shearon Harris 1 in New Hill, NC, was the last US reactor to receive a construction license, on 27 January 1978. And it turns out that, while the affirmative findings for Watts Bar 1 were made on 19 December 1972, the license didn’t issue until 23 January 1973 because of an odd appeal.

8

Thank you for clearing that up, Qwertz

9

I can tell you that the “alternates” - solar, wind, etc - are crap.

Solar power is actually pretty good at heating for domestic hot water uses. It’s free and fairly efficient – at least where I live since the sun is plentiful. Not much else you could do with it though.

I was actually reading about designing sky scrapers with built in solar panels which acts as a supplement power source, which saves about 10% on energy cost. Pretty cool idea, especially as oil gets more and more expensive. As a primary source of power however it is completely inviable given the current technology, given the cost and the low rate of energy conversion when compared with fossil fuel. But I do think that it is a promising field that could potentially change the way we live (economically, architecturally, etc).

10

The idea that there has to be a single global answer is just so strange. The answer is “whatever is most profitable, in the long term”. That’s an economic question, not an engineering one."

Actually it’s a bit of both. Different types can coexist quite happily on the same one grid even under laissez-faire because they have different purposes and different costing structures, all because of different operating regimes due to their engineering. Additionally, a large part of the solution is the meeting of range-of-the-moment needs, shifting from minute to minute, rather than focusing entirely on long-term needs - again, because of engineering as much as economics.

The big and heavy stations - coal, nuclear, oil, hydro - are best at supplying what’s called the base-load, and are cheap at supplying power by the hundreds of megawatts or more. However, they are slow to ramp up and down precisely because they’re big and heavy (gigantic synchronous generators dozens of yards long and a few yards in diameter, weighing umpteen tons, plus thermal inertia of all that boiler water etc). Thus into the breach step in the smaller and more expensive supplies, such as gas and diesel, to pick up the slack in much smaller 1-10 megawatt lots while the baseload suppliers catch up or don’t even bother trying to do so at all. This is why there are substantial price reductions for major and constant users plus electricity consumption in the wee small hours: the more that demand can be kept more constant and spread out evenly through the day the more can be handled satisfactorily by the base-load suppliers at lower average unit cost without resorting to making demands on the more expensive peak suppliers.

The smaller and more expensive supplies are also common when the grid at ordinary is in the vicinity of full capacity of the base load and it is not economically viable to add in scads of more base load capacity yet. Economies of scale require sufficient scale to be economical, you see. For instance, even under laissez-faire you wouldn’t get much change from a billion dollars for a big-ass nuclear reactor supplying a gigawatt plus at one cent per kilowatt-hour, but a 20 megawatt gas turbine will set you back less than $50m even though the supply will cost say five cents per kilowatt-hour. So if a given region’s load isn’t expected to grow appreciably then the extra power demand will again be picked up by supplies that are more expensive on average but involve significantly lower capital outlays - and it is the cost of capital, not the cost of operation, that is the bulk of what goes into electricity prices, especially for base-load supplies.

Note also that the smaller the unit supplying the electricity, the easier it is it can be picked up and moved wherever. Gigawatt stations ain’t moving nowhere, while diesels supplying a megawatt or two are regularly hauled around by trucks and delivered to places on temporary hire contract. Mobility has value.

When you get to ultra remote supplies, the more expensive supplies can and do supply the base as well as the peak, as David pointed out. I’d also add that there are instances when “alternative” supplies are valid and viable. Phone booths in outback Australia are solar powered because nothing else is as viable in such incredibly remote locations for so little power demand, and the sugar refineries in Queensland make a lot of use of burning unwanted cane biomass and sugar-production residue to power their operations because the stuff is going to get burnt off anyway so it may as well be used productively.

JJM

11

In the US, the NRC issues operating licenses and site licenses. You need a site license to build, and an operating license to operate. Watts Bar 1 got its operating license in 1996 and went online in 1997, but it got its site license in 1972 or 1973. The “30 years” figure refers to site licenses, not to operating licenses. Watts Bar 2 (the second reactor at the site) just recommenced construction last month, under its original '70s site license (each reactor requires its own licenses). While Watts Bar 1 was the last to come online in the US, I do not know if it was the last to receive a site license. I’ll look it up if I get a chance.

~Q

Correction: Watts Bar 1 and 2 share a site license, granted 19 December 1972.

Further update: Shearon Harris 1 in New Hill, NC, was the last US reactor to receive a construction license, on 27 January 1978. And it turns out that, while the affirmative findings for Watts Bar 1 were made on 19 December 1972, the license didn’t issue until 23 January 1973 because of an odd appeal.

A friend of mine who works at Progress Energy mentioned that they were planning on building new nuclear plants. Here is a news article. Of course we’ll have to see what really happens.

http://www.seekingalpha.com/article/1659-p…wer-plant-plans

12

Shearon Harris was originally planned as a four reactor complex, but the other three were never built. Now they want to build more, and are beginning the licensing process. Two new reactors were granted early site licenses in 2006.

Turns out that there are actually three licenses: the early site license, the construction license, and the operating license. Early site licenses are the easiest to get, and NRC has never stopped granting them. They are prospective licenses that do not require extensive design studies, but do require initial environmental impact studies. Operating licenses likewise were never on hiatus like construction licenses were, but there haven’t been any new reactors being completed since 1996 (Watts Bar I). There is currently only one unfinished plant in the US still under an active construction license (Bellefonte, 2 reactors), and I may have read a news article published since the last NRC digest that said something about the Bellefonte construction licenses being revoked. Sometime in the past few months. This may have been a procedural move, because I think Bellefonte will use different reactor design than originally planned, so it would have needed new construction licenses. As of Oct 30 this year, Bellefonte has submitted applications for an operating license. Query whether Bellefonte, originally authorized back in the nuclear power heyday, falls under the new Nuclear Power 2010 program.

~Q [a.k.a. Obsessive Nuclear Fanboy]

13

I think the fact that we cannot/willnot reprocess spent fuel (i.e., remove the small fraction of fission products from an otherwise good fuel rod) also makes things worse for nuclear power economically. Basically something like 98% (or some similar large fraction; feel free to correct me!) of the nuclear fuel is simply thrown away.

Which also means the waste disposal issue is unecessarily made far greater than it ought to be.

14

I think the fact that we cannot/willnot reprocess spent fuel (i.e., remove the small fraction of fission products from an otherwise good fuel rod) also makes things worse for nuclear power economically. Basically something like 98% (or some similar large fraction; feel free to correct me!) of the nuclear fuel is simply thrown away.

Which also means the waste disposal issue is unecessarily made far greater than it ought to be.

Moreover, Julian Simon in Ultimate Resource 2 (pp209-211) pointed out how much of a non-issue nuclear waste disposal should be. The fears are all flat-out irrational. He quoted Fred and Geoffrey Hoyle, who actually did the sums and figured out that the grand total share of vitrified waste that would be generated from an entire 70 year life’s worth of consumption of a four-member family fueled entirely by nuclear power would fit into a sphere the size of a small orange weighing just 2kg (4.4lb). Because the radioactivity only has a certain life-span, the accumulation for a city of half a million would only grow to what fits inside 15-20 ordinary warehouses, and stay at that level permanently as old ‘oranges’ become safe to throw away and make room for new ones. He goes on to point out that Petr Beckmann calculated that a single person’s share of high-grade waste per year could fit in the volume of two aspirin tablets. After 100 years those tablets would be less radioactive than the natural ore the uranium came from, and after 500 years be less dangerous than fly-ash from coal-fired power stations.

Anyway, if memory serves me, I think part of the Official Excuse for non-processing of fuel rods is that it opens up the door for extraction of plutonium and other radioactive substances for nefarious purposes. Treaties on non-proliferation of nuclear weapons may also have something to do with it. Either way, it translates to meaning not having the balls to say a blunt NO with threat of bombings to the likes of the Iranians or Norks.

JJM

15

Fascinating stuff John; thank you for sharing that information.

16

What would you argue should be the primary energy source to power the country/globe?

Obviously the most effecient and profitable when all valid concerns are taken into account. With that, in the near term certainly nuclear is the best, augmented by breeder reactors. After that, solar power would probably become viable and provide the bridge to real fusion energy.

In the near term, breeder nuclear fission is the way to go. Breeder reactors can generate 10 - 100 times as much energy with the same amount of fuel that a conventional nuclear reactor does as the breed more fuel from the by products of the fission process. The biggest concern with breeder reactors is they generate nuclear weapons grade plutonium as a by product, but you can actually use the waste that nuclear reactors create to help shield the reactors, simaltaneously getting rid of the ‘storage’ problem of waste, which isnt as much of a problem as people make it out to be, and removing any possible threat of acquiring weapons grade material, since the nuclear waste never leaves the reactor until it has undergone all its fissioning and turns into iron. You can use the radiation from fission reactions to accelerate the radioactive decay of other elements (this is exactly what the fission process does to uranium) bombarding radioactive elements with high energy nuetrons (nuetrons need to be slowed in controlled fission reactions) will encourage those radioactive elements to further decay, the curve of nuclear binding energy peaks at iron, so all heavy elements will fission into iron eventually.

Ideally, a dozen or breeder plants, in underground isolated facilities, could generate enough power for the whole nation, and enough to manufacture synthetic liquid fuels at competitive costs (so our vehicles can still travel decent distances) the plants would consume their own waste reducing it to iron.

This past week, as part of an organization I am a member of, I met with the Navy War colleges Strategic Studies Group and ended up at some point going on this same rant, this was a group of top engineers and admirals / captians, etc in the Navy, and these guys who knew what I was talking about were enthusiastically nodding, so I think (or hope) that thoughts like this are going around in areas that matter.

Incidently, Texas is on the verge of building a new reactor, I have heard that the licenses have been approved, but can’t find a recent news link stating as much.

http://www.world-nuclear-news.org/newNucle…on_131107.shtml

I’m pretty sick of this whole funding terrorist breeding murderous dictatorships economy we have now, especially when we have a perfectly good alternative.