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« Off To The Land Of Enchantment | Main | In NM »

Zero Divided By Zero = Space Solar Power

Taylor Dinerman thinks that solar power is the answer to China's future electric power woes:

While China may turn to widespread use of nuclear power plants, the Communist Party leadership is certainly aware of the role that glasnost and the Chernobyl disaster played in the downfall of another Communist superpower. Thus, China may be reluctant to rely heavily on nuclear power plants, at least not without strong safety measures, thus making them more expensive and more time consuming to build. Wind power and terrestrial solar power will not be able to contribute much to meeting Chinaís demand and certainly not without government subsidies which a relatively poor nation such as China will be reluctant to provide.
At some point within the next twenty or thirty years China will face an energy crisis for which it will be almost certainly unprepared. The crisis may come sooner if, due to a combination of internal and external pressures, the Chinese are forced to limit the use of coal and similar fuels.

No evidence is available to suggest that China will be "forced" to pay for solar vs. six-cent coal. No evidence is presented to suggest that China will allow the US to have an off switch for its power grid vs. paying extra for local terrestrial solar. No evidence is presented showing that space solar will be cheaper than terrestrial solar at expected launch prices. No evidence is presented that the world will have sufficient launch capacity to make a dent in Chinese demand.

To focus on one link in this chain, it will require launch prices to fall below three times manufacturing costs of solar for space solar to be competitive with Earth solar which would require launch costs of less than $500/kg given solar manufacturing of about $170/kg now (and that is falling at 5%/year so it might be $150/kg that is the moving target to beat terrestrial solar in the 2030s). It would require many times existing launch capacity to come on line at that price to deliver sufficient wattage. If launch prices do fall toward that rate, a vibrant tourism and off-earth living industry will become viable ($150k for a one-week stay in orbit which will be only twice the annual US per capita GDP in 30 years). That would prevent launch costs from dropping further until that market becomes saturated.

And terrestrial solar is only about 0.1% of electricity supply now so if space solar can't beat that...

Posted by Sam Dinkin at October 22, 2007 12:35 PM
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The Chernobyl disaster killed 56 people total over the past 21 years. That's about how many die annually in the fossil power business. As for the thousand square kilometers evacuated, the people who refused to leave are being monitored for health effects. Not much happened, so the exclusion zone is now down to 10 km radius. The other two reactors on site ran commercially for several years before being shut down. Soviet era reactors of that design are gradually being shut down and replaced. New reactor designs are several orders of magnitude safer (no exaggeration). Even the "old" Three Mile Island reactor killed zero people, injured zero people when it melted down. Modern designs are far better than TMI, which was far better than Chernobyl. Ukraine (where that one was) has 2 new reactors on order. Russia has 3 modern design commercial power reactors under construction with one each in Pakistan and Romania. China has 5 under construction and India 7. Two more each in Japan and Taiwan. Altogether 28 commercial power reactors are being built around the world and NONE in the USA, if you don't count the old TVA project that has been restarted. (There may be one fewer; the one that was nearing completion in Iran may be having .... technical difficulties)

Meanwhile, coal burning power plants EACH blow about 20,000 tons of CO2 into the atmosphere daily. The ratio of CO2 to electricity from burning coal is about 1 kg per kWh. I don't know if that's bad, but Al Gore has a lot of followers.

Yes, new nuclear power plants are more expensive to build than older, less safe designs. They are now about as expensive as the cheapest alternative: coal burning at about $.02 per kWh. There is one big difference between the cost of coal fired plants and nuclear plants. The cost of waste storage and dismantling is included for nukes but not fossil burners. Although China has started a program to mine uranium from coal ash.

Most references are from www.uic.com.au.

Posted by Dan DeLong at October 22, 2007 01:53 PM

Chernobyl didn't even have a containment building. And the folks doing the experiment at the time turned off each alarm as it went off.

Even if China built their nuclear power plants cheap and cut corners, unless they're built and operated with *astounding* incompetence, I doubt they'd have the same risk as Chernobyl.

Posted by Roger Strong at October 22, 2007 02:28 PM

Coal plants also emit significant radioactivity, from impurities in the coal, which is just about impossible to reduce. In fact, the radiation load from a coal plant is an order of magnitude or so more than the routine emissions from a nuke plant.

Posted by Fletcher Christian at October 22, 2007 03:50 PM

Not that I think it's likely to happen, but in-orbit construction would lower the lauch costs quite a bit. You'd have to get the raw materials from the Moon or an asteroid, but lifting a manufacturing capacity once may be cheaper than lifting all of the facilities from Earth. Harder (much harder), but possibly cheaper.

China's gradutating what, 100,000 engineers a year? They may not be MIT quality, but they've got man-hours to spare.

Posted by Brock at October 22, 2007 05:27 PM

I second Fletcher's comment. Radioactive elements embedded in natural coal are a larger source of radioactivity.

Posted by Al at October 22, 2007 06:05 PM

There's also the one little issue with SPS that nobody mentions... if we depend on one for half of our power, what happens when China shoots it down?

Or, what happens when they threaten to shoot it down if, say, we don't give them exactly what they want?

Posted by Big D at October 22, 2007 06:50 PM

"That's about how many (56) die annually in the fossil power business."

Checked the mortality rate for Chinese coal miners? Thousand of workers die each year in Chinese coal mines. I think the rate for 2006 was over 3000.

Posted by John Kavanagh at October 22, 2007 07:16 PM

China (and the US) will go for the cheapest power given all factors domestic and international including forgone CO2 reduction sales, international treaties and obligations and response to environmental pressure groups. That may be coal primarily until China gets rich enough for an environmental movement, then nukes. Without western subsidies in China, wind installations will be attracted to other more tax friendly locations because China won't be so interested in subsidizing clean power for another 15-25 years until its population hits the income level of 1970s America (about $20k per capita in current dollars). Similarly, China won't want (or equivalently be able to afford) to pay for expensive clean power relative to Western nations. The clean energy buyers will be predominantly from rich countries until those markets are saturated.

Posted by Sam Dinkin at October 22, 2007 08:09 PM

So how many square kilometers of space solar power would we need if, say, we wanted to replace all the electricity from our coal burning plants?

Posted by lmg at October 22, 2007 08:22 PM

Here are two reports about wind power in China.

The first is a detailed overview published in mid 2006

And the second is a recent press release from the Irish research house "Research and Markets"

The renewable market in China is booming and like most things in China the price for much of this technology will collapse over the next 10 years.

Chances are that the only problem with energy in 50 years will be what to do with it all.

Posted by Simon at October 23, 2007 05:40 AM

There's also the one little issue with SPS that nobody mentions... if we depend on one for half of our power, what happens when China shoots it down?

1. Is there a power station today that US depends on for half of its power? No, and there should not be in the future either. You don't build one SPS, you build many, and destruction of any one is no more consequential than destruction of one powerplant now.

2. Defensive weapons. Powerplants may be civilian installations, but they are protected, up to and including (in France, for example) with anti-aircraft missiles. To preclude obvious smartass comments, you do not put guards with dogs on SPS -- you put defensive weapons corresponding to potential threat.

3. An SPS is part of your national territory. What would be the response today if China dropped an FAE on Hoover Dam? An attack on SPS should be treated the same way.

But 1. is the most important, and not just with regard to hostile actions. Don't put all your eggs in one basket.

Posted by Ilya at October 23, 2007 06:24 AM

I'm in favor of great expansion of nuclear power, but some of the 'pro' arguments used in this thread are bogus.

First, the 56 deaths from Chernobyl ignores the slight increase in general cancers that can be reasonably infered under the assumption of linear, no-threshold response (yes, I know some people claim this theory is wrong, but such a dismissal is not justified by the evidence; it's even possible that low dose radiation is even more effective at causing cancer, making the prediction of LNT an underestimate). Since cancer is so common, even a slight (and statistically impossible to detect) increase could involve thousands of deaths.

Second, the bit about coal plants putting out more radioactivity than nuclear plants is only the case if you ignore emissions from nuclear accidents, reprocessing, and uranium mining. The last two are the dominant sources in western countries, particularly if 14C is not captured at reprocessing time (although the dose from 14C is spread over thousands of years).

Posted by Paul Dietz at October 23, 2007 06:45 AM

Paul,

You are ingnoring the large amounts of aerosolized uranium and thorium released from the burning of coal.

Posted by Mike Puckett at October 23, 2007 07:07 AM

Here's a link to the study on solar Taylor referred to.

China can fire plastic pellets around the Moon and send them into a retrograde orbit wipe out all of satellites in GEO. It is a pretty silly thing to do since almost every country would have satellite TV users that would now hate China forever. There are much more effective ways for China to hurt us like shooting nuclear weapons at us.

If launch prices are $300/kg, killing a solar satellite is no more or less annoying than bombing a fossil fuel plant. Once space based solar power is economical, the strategic value of existing GEO assets goes down because spares and replacements are so cheap.

Posted by Sam Dinkin at October 23, 2007 07:35 AM

You are ingnoring the large amounts of aerosolized uranium and thorium released from the burning of coal.

No, I am not.

Posted by Paul Dietz at October 23, 2007 07:44 AM

Additional comments: in the US, a 1 GW(e) coal plant will annually consume coal containing about 5 tons of uraniuma and 12 tons of thorium. These elements mostly go into the fly ash, but fly ash is also mostly captured, not released into the atmosphere.

A 1 GW(e) nuclear reactor will require somewhere in excess of 100 tons of natural uranium per year (suitably enriched so the actual amount of uranium in the fuel elements replaced each year is less.) So the total amount of radioactivity mobilized at the uranium mine exceeds that mobilized by coal combustion.

In either case the impact is not terribly significant, particularly if some care is taken.

It's not clear to me that all the radioactive daughter species (like, say, polonium) end up in fly ash, but I expect most of the Po would be taken out in the sulfur scrubber.

Posted by Paul Dietz at October 23, 2007 09:08 AM

"China can fire plastic pellets around the Moon and send them into a retrograde orbit wipe out all of satellites in GEO. It is a pretty silly thing to do since almost every country would have satellite TV users that would now hate China forever. There are much more effective ways for China to hurt us like shooting nuclear weapons at us."

One would suspect that the Chinese would do both.

Posted by Mark R. Whittington at October 23, 2007 09:58 AM

The clean energy buyers will be predominantly from rich countries until those markets are saturated.

I keep seeing this but it makes little sense anymore. China has 1 TRILLION dollars worth of U.S. dollars as direct cash in the form of treasuries that they have bought over the years.

That buys a lot of whatever the hell they want to buy.


Posted by at October 23, 2007 10:59 AM

Regarding the question of what is done if China starts shooting at the SPS stations, Heinlein had the answer fifty years ago. (Moon is a Harsh Mistress, anyone?) Especially since the only really feasible way of building the things is using lunar materials, launched using a giant railgun (or similar).

Drop rocks on them. Big rocks. Lots of big rocks, at escape velocity. Messy.

Incidentally, the same treatment could be used for Arab countries that restart the funding of terrorists. I say "restart" because in my humble opinion, the first thing to do with a lunar launcher is to tell those people to play nice or the Hammer gets dropped. And then demonstrate exactly what we mean.

Posted by Fletcher Christian at October 23, 2007 12:22 PM

Paul:
Slight increase of the cancer rate from radioactivity is the commonly accepted theory, especially by those with a vested interest (Greenpeace, tort lawyers, etc) but there is a growing body of evidence that an elevated background level lowers the cancer rate. Do a search on Taiwan Radioactive Apartments Cancer Dose.

Sam: I didn't mean to hijack your SPS thread. I LIKE the idea of SPS, and I look forward to making lots of money launching them, but you can't just go buy one. In the meantime, it's a development effort.

Posted by Dan DeLong at October 23, 2007 12:27 PM

Fletcher --

Heinlein grossly overestimated the destructive power of kinetic projectiles from the Moon. An object falling from Moon's distance enters the atmosphere at 11.1 km/sec -- which translates into about 17 times its mass in TNT. Nothing to sneeze at, but far from nuclear range unless these slugs measured thousands of tons. Heinlein never said how much they did mass, but that value is absurd.

Posted by Ilya at October 23, 2007 12:31 PM

but there is a growing body of evidence that an elevated background level lowers the cancer rate. Do a search on Taiwan Radioactive Apartments Cancer Dose.

Unless these putative apartment results were for millions of people, any epidemiological evidence from them cannot say anything about the effect of low level radiation -- the predicted effect is simply too small to rise above the statistical noise.

I note that the doses in this study are far higher than the doses that most people would have been exposed to from Chernobyl. Additionally, the study is going to have problems with confounding factors, since the people living in these apartments were not selected randomly from the population.

I will also add that the claimed Taiwan results (cancer reduced to 3.24% of the normal level!) are so extreme that one would expect to see similar massive signals from high natural radiation areas. Such effects are not seen.

Posted by Paul Dietz at October 23, 2007 01:41 PM

Given the time and effort that we know the Chinese are expending on cyber-warfare, why in the world would they be firing pellets (or anything else) at the power satellites?

Why not hijack them, either pointing the collectors in the wrong direction, or better yet, beaming the power down to the wrong location?

That's presuming, of course, they decide to take active action at all.

Posted by Lurking Observer at October 23, 2007 02:02 PM

Nothing to sneeze at, but far from nuclear range unless these slugs measured thousands of tons. Heinlein never said how much they did mass, but that value is absurd.

Is it? I've always pictured Heinlein's grain barges being 'cargo container' sized - but this might be wrong considering the amount of food they were shipping to Earth.

A twenty foot container has a max gross weight of 52,910 lbs. 78 of those would be 4,021,160 pounds or 2,010.58 tons. That's a close measure of 'thousands of tons'.

(This might not be right but since we can't go and ask him what he had in mind so educated guessing is what we've got. Unless the tonage per day figure and number of launches per day is in Harsh Mistress ... )

That still sounds like a lot but the capacity of modern container ships varies between 7,000 to 15,000 20 foot containers.

So we're talking about a very small amount of cargo compared to what we're sending across the ocean today. Essentially the Loonies were lobbing small cargo ships to the Indians and as bombs to the rest of us.

Heinlein was supposed to be pretty good at his background - I'd sooner believe he intended 'cargo ship sized' bombs before believing he made a mistake with math.

Cargo container vessel info here - http://en.wikipedia.org/wiki/Container_ship

Containerization data here -
http://en.wikipedia.org/wiki/Containerization

Posted by Brian at October 23, 2007 02:07 PM

Meanwhile, coal burning power plants EACH blow about 20,000 tons of CO2 into the atmosphere daily. The ratio of CO2 to electricity from burning coal is about 1 kg per kWh. I don't know if that's bad, but Al Gore has a lot of followers.

I read a while back someone had done a survey on the northeast power outage of '03, and that within 24 hours, most of the atmospheric pollutants had settled out of the air, making it very clean. While that shouldn't be seen as justifying continuing to belch CO2 out like crazy, it does bode well for how the atmosphere will clean up if we migrate away from coal.

Posted by Rick C at October 23, 2007 02:29 PM

Meanwhile, coal burning power plants EACH blow about 20,000 tons of CO2 into the atmosphere daily. The ratio of CO2 to electricity from burning coal is about 1 kg per kWh. I don't know if that's bad, but Al Gore has a lot of followers.

I read a while back someone had done a survey on the northeast power outage of '03, and that within 24 hours, most of the atmospheric pollutants had settled out of the air, making it very clean. While that shouldn't be seen as justifying continuing to belch CO2 out like crazy, it does bode well for how the atmosphere will clean up if we migrate away from coal.

Posted by Rick C at October 23, 2007 02:35 PM

I wouldn't worry to much about the Chinese attacking our solar power satellites. We won't be beaming power to the U.S. for a long time. We'll send it where we can get the best prices, up to 3 times our prices in some countries and probably more. For a long time, the power will be going to island nations, Central and South America, Africa, India, some European nations, and probably China, if they want to resume breathing. Anyone who attacks our power sats will piss off huge numbers of people, but do little direct damage to us.

Posted by Gary at October 23, 2007 03:02 PM

So how many square kilometers of space solar power would we need if, say, we wanted to replace all the electricity from our coal burning plants?

Posted by lmg at October 22, 2007 08:22 PM

A mere 680 km^2. Only a 26,000 m x 26,000 m array. Thatís neglecting transmission losses, I donít know much about microwave conversion efficiency, but Iíd guess you need to multiply that number by 16 or so. At current array prices your total cost is only 4 quadrillion dollars. Based on typical spacecraft lifetimes you might even get about Ĺ the life of your average nuclear power plant.

A quadrillion here a quadrillion there and pretty soon youíre talking about real money!

Posted by brian d at October 23, 2007 03:13 PM

Ilya:

I think you're wrong. I seem to remember that the stated (in the book) mass of the barges was about a hundred tons. Using your figures, that translates to a couple of kilotons of TNT more or less.

That isn't a continent-wrecker, but you can fire LOTS of them, and very accurately at that. In the book, the barges were replaced with actual rocks plated with metal, the launcher was uprated - and they took out Cheyenne Mountain by the simple expedient of hitting it over and over and over again.

"Mannie, I don't think we should hit that mountain again." "Why, Mike?" "Because it isn't there any more."

Also, major-scale space infrastructure implies, and possibly requires, the ability to divert things a bit bigger than Lunar boulders.

Posted by Fletcher Christian at October 23, 2007 03:21 PM

Dinerman's articles often include science fiction elements. Remember his prediction that the US would fund a "space battle station" in this year's budget? He's also a big fan of massively complicated space programs. He has written at least several articles calling for large military spacecraft constellations for early warning, or providing beamed solar power to fleets of satellites in low Earth orbit. He does not factor cost into any of his big ideas. There's no reason to take his concepts seriously.

Posted by Mike Hirst at October 23, 2007 08:57 PM

well, I will be interested to see how the Chinese deal with the economics of launch for their SSP solution.

Last year, the told me they were down to 2000 dollars per kg payload (cost), so they still have a factor of 4 to go at least.

If US experience is any guide, economies of scale will be hard to achieve. I took a quick look at Minuteman III's the other day - over 500 of them produced but preliminary numbers suggest it still equates to a flyaway cost of 4000 dollars per kg of payload to LEO...

Posted by Kevin Parkin at October 24, 2007 05:41 AM

You'd have to get the raw materials from the Moon or an asteroid, but lifting a manufacturing capacity once may be cheaper than lifting all of the facilities from Earth. Harder (much harder), but possibly cheaper.

One study estimated that by the time you had built 30 SPS, the lift-cost savings would have paid for the investment in space infrastructure.

Posted by Mike Combs at October 24, 2007 06:32 AM

Dan: I want there to be space based solar power, but I don't think it's going to be here in 20 years unless you can get launch costs down to less than $500/kg to GEO. That is, Tailor is putting the cart (SBSP) before the horse (low cost high volume space access). SBSP will not be profitable before tourism and settlement is profitable even given a factor of 10 decrease in the demand curve in kilos for tourism implied by Futron. In the mean time, beaming power into space by laser is probably better business.

Posted by Sam Dinkin at October 24, 2007 10:50 AM

Sam: supply and demand are a chicken and egg problem. They need to develop together, but demand is more important. We've been trying supply push with space transportation without very good results. Demand pull from tourism, SBSP, etc. should work better. Hard-nosed investors want to see the market.

BTW, this illustrates a point made wonderfully clear by Heinlein in For Us, the Living. Supply-side economics is inferior because demand is a far more important economic driver in modern industrial economies. Highly recommended.

Posted by Gary at October 25, 2007 01:42 AM

If US experience is any guide, economies of scale will be hard to achieve. I took a quick look at Minuteman III's the other day - over 500 of them produced but preliminary numbers suggest it still equates to a flyaway cost of 4000 dollars per kg of payload to LEO...

That sounds pretty good actually. Recall that the Minuteman is designed to delivery nuclear payloads with great accuracy in the midst of a nuclear war. So it has substantial military requirements. Also, it's a suborbital rocket. So any payload to orbit is incidental.

Finally, let us keep in mind that at the time the Minuteman was deployed (in the 70's), launch costs were substantially higher. I'd say as much as a factor of 10 higher. To me that indicates substantial economies of scale.

Posted by Karl Hallowell at October 27, 2007 09:58 AM

Paul, I've been glancing through your claims about radiation and I just don't buy them. To point out what you just stated, natural areas vary greatly in background radiation. If there was a significant effect one waty or another in minute radiation doses, surely we'd have seen it by now.

Second, one doesn't get to speak of the radiactive material "mobilized" by uranium mining so casually. First, coal mining mobilizes substantial radiative material as well both in the overburden and in noncoal material mixed in with coal. Second, most of the uranium (the lion's share of the radioactive material in uranium mines) is demobilized later either when depleted uranium enters the US strategic reserve or gets inserted into a nuclear plant. In comparison, fly ash from coal burning can end up in the air, in construction materials (as an ingredient for concrete), or in a landfill. Only some of that demobilizes the radiation released from coal burning.

Sure somewhat more radioactive material might be "mobilized" by uranium mining than by coal mining and burning, but my take is that the latter is more likely to end up inside human beings. That is, it is more mobile in a way that harms humans.

Posted by Karl Hallowell at October 27, 2007 10:30 PM

Paul, I've been glancing through your claims about radiation and I just don't buy them. To point out what you just stated, natural areas vary greatly in background radiation. If there was a significant effect one waty or another in minute radiation doses, surely we'd have seen it by now.

So, implicitly, the mainstream scientists who have studied radiation biology effects must have screwed this up, but you, Karl Hallowell, have seen things clearly.

Maybe, just maybe, you should realize that is unlikely and you have made a mistake in your thinking?

The LNT theory predicts an effect from natural radiation areas, but the effect is low enough that it's swamped by other sources of variability (diet, lifestyle, genetics, and so on). In contrast, the effect predicted by that putative Taiwan aparement effect is far larger and would have stuck out like a sore thumb.

For what real scientists, as opposed to internet crank pseudoscientists, say about LNT, read this review article

http://www.pnas.org/cgi/content/full/100/24/13761

Posted by Paul dietz at October 28, 2007 01:42 PM

So, implicitly, the mainstream scientists who have studied radiation biology effects must have screwed this up, but you, Karl Hallowell, have seen things clearly.

Show me credible research that low radiation or toxin doses cause harm for substances that are already present at a high level in the environment naturally and I'll change my tune. My take is that you won't find it. The problem is that detection of a small increase in harm from a small dose requires a large test group, a stumbling block in the way of all such research.

Second, the paper you cite is weak. They extrapolate outside of the area where they have data based on a poor model. They assume that the body has no means of repairing inflicted radiation damage. These are two obvious flaws with the paper.

Posted by Karl Hallowell at October 29, 2007 02:15 AM

In case my first paragraph just above wasn't clear, I claim that scientists have not yet conducted enough research into very low doses to support your claims.

Posted by Karl Hallowell at October 29, 2007 02:20 AM

In case my first paragraph just above wasn't clear, I claim that scientists have not yet conducted enough research into very low doses to support your claims.

This just shows your lack of reading comprehension, Karl.

I am not claiming that LNT is correct. I am claiming it is not ruled out. In particular, I was debunking DeLong's false claim that "there is a growing body of evidence that an elevated background level lowers the cancer rate."

I readily admit that LNT will be difficult, or even impossible, to decisively prove at sufficiently low doses. But this doesn't mean that the favorite internet crank theory IS supported, or even that LNT is an overestimate! It's consistent with the evidence that LNT UNDERESTIMATES the marginal change in cancer rate from small changes in radiation doses at low dose rates.

Posted by Paul Dietz at November 9, 2007 11:53 AM


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