Is 450 ppm (or less) politically possible? Part 1

tilting.jpgThe short answer is, “Not today — not even close.”

The long answer is the subject of this post (and my book and this entire blog).

Certainly regular readers know that the nation and the world currently lack the political will to stabilize atmospheric concentrations of carbon dioxide at 450 ppm or even 550 ppm.

The political impossibility is also obvious from anyone familiar with Princeton’s “stabilization wedges” — and if you aren’t, you should be (technical paper here, less technical one here). The wedges are a valuable conceptual tool for showing the immense scale needed for the solution (although they have analytical flaws).

Of course, if solving the climate problem were politically possible today, I would have found something more useful to do with my time (as, I expect, would you). But 450 ppm or lower is certainly achievable from an economic and technological perspective. Indeed, that is the point of the wedges discussion (since they rely on existing technology) and the Conclusion to Hell and High Water.

The purpose of my last post on the adaptation trap was to make clear that 800 to 1000 ppm, which is where we are headed, is a catastrophe that is far beyond human imagining, that makes a mockery of the word “adaptation,” that has a “cost” far beyond that considered by any traditional economic cost-benefit analysis. It is both a rationally impossible and morally impossible choice. So, I think is 550 ppm, assuming we could stop there, which as I argued, we probably can’t thanks to the carbon cycle feedbacks like the melting tundra.

What needs to be done?


[Note: I am going to do this entire post in billions of tons of carbon (GtC) even though I just wrote a long post explaining why carbon dioxide is better. That’s because the wedges were formulated in GtC and are much more intuitive that way.]

As Princeton’s Robert Socolow and Stephen Pacala (S&P) explain:

A wedge represents an activity that reduces emissions to the atmosphere that starts at zero today and increases linearly until it accounts for 1 GtC/year of reduced carbon emissions in 50 years. It thus represents a cumulative total of 25 GtC of reduced emissions over 50 years.

They wrote their Science paper when we were at 7 GtC and rising slowly — an ancient time you may remember as 2003, before Bush was reelected, before anybody ever heard of Reverend Wright or Paris Hilton or the need to stabilize below 450 ppm. An innocent time, really, but I digress.

So they said that 7 wedges would keep emissions flat for 50 years and then, assuming we invested in a lot of R&D, we could start cutting global emissions rapidly after 2050, and stabilize at 500 ppm. And everybody would live happily ever after driving fuel cell cars, watching YouTube, and popping the occasional Xanax.

Problem 1: The world is at 8 GtC annual emissions.

Just to stabilize emissions at current levels thus requires adopting at least 8 wedges.

Problem 2: S&P assume “Our BAU [business as usual] simply continues the 1.5% annual carbon emissions growth of the past 30 years.” Oops! Since 2000, we’ve been rising at 3% per year (thank you, China). That means instead of BAU doubling to 16 GtC in 50 years, we would, absent the wedges, double in 25 years. That would mean each wedge needs to occur in half the time, assuming our current China-driven pace is the new norm (which is impossible to know, but I personally doubt it is).

Problem 3: A wedge is a mind-bogglingly large amount of “activity.” For instance, a post last year on the Keystone report explained that one nuclear wedge would require adding globally:

  • an average of 14 plants each year for the next 50 years, while building an average of 7.4 plants a year to replace those that will be retired;
  • Plus 10 Yucca Mountains to store the waste.

If you believe 3% growth is the new norm, then double that — 43 nukes a year for 25 years — for one wedge.

One wedge of coal with carbon capture and storage means storing the emissions from 800 large coal plants (4/5ths of all coal plants in 2000) — a flow of CO2 into the ground equal to the current flow of oil out of the ground. That’s right — you have to re-create the equivalent of the planet’s entire oil delivery infrastructure.

So one wedge from nuclear and one from CCS would be a stunning global achievement. Those who want to rule them out need 2 more wedges.

Here are other typical wedges (these are examples, not endorsements):

  • If we built two million large (one megawatt) wind turbines, or 2000 GW. “Last year’s global wind power installations reached a record 20,000 MW, equivalent to 20 large-size 1 GW conventional power plants.” So we’re at half the rate needed for 1 wedge of wind (or mayber a quarter).
  • If the fuel economy of the 2 billion or so cars in the world in 2050 got 60 mpg, that would be one wedge.
  • For the conservation/peak oil folks, if the 2 billion cars in 2050 travel 5000 miles a year, rather than 10,000.
  • If we grew biofuels requiring one-sixth of the world cropland.
  • For S&P, ending all deforestation and doubling the current rate of tree planting is one wedge. In fact, if we don’t sharply reduce deforestation, we probably need to add another two wegdes (S&P used optimistic numbers for deforestation).

Problem 4: Stabiling emissions at current levels for 50 years and then declining sharply would probably not stabilize us below 600 ppm (even assuming that 1.5% annual growth was BAU, and not 3%).

For 450 ppm, we need to average 5 GtC this century. So we must be back down below 4 GtC globally by mid-century (and then head to zero by century’s end). Thus we need a minimum of 12 wedges if we started last year, which we didn’t. We probably won’t start putting serious measures into place before 2010 at the earliest, when we’ll be at 9 GtC. So that is 2 more wedges.

[Yes, I know, know, why in God’s name did we elect and reelect two oil men who would spend their entire time in office not merely blocking all domestic action, but all international action, too. That is one for the history books, I’m afraid. What is especially depressing is that China’s torrid love affair with coal plants only began after 2000, after it was clear the U.S. wouldn’t take any action…. As Richard the III might have put it, a time machine, a time machine, my Kingdom for a time machine….]

Problem 5: The baseline of the wedges is unknown even to the the original authors, S&P. This is related to Problem 2.

[You can skip this problem if arcane baseline stuff is not your cup of arsenic. It may, however, mean a bunch of other wedges are needed, though (or not).]

That is to say, no one knows what amount of wind, nuclear, or efficiency is in Princeton’s business-as-usual case — including S&P themselves. So the wedges provide you only a conceptual feel for what we need to do, not an analytically rigorous answer. The fact that emissions have been rising 3% a year since 2000, rather than 1.5% as S&P assume, is another example of how S&P don’t know what BAU is.

What does this mean? Well, S&P claim that one possible wedge is “Introduce CCS at synfuels plants producing 30 million barrels a day from coal [about one-third current oil demand], if half of feedstock carbon is” captured and stored. I have argued with Socolow many times — [welcome to my world!] — that 30 million barrels a day of synfuels (liquid coal) is NOT in the business as usual baseline — that is, CO2 emissions could (and would) grow 1.5% per year without any synfuels production. If I’m right, then synfuels even with CCS makes the climate problem worse. Synfuels without CCS is, of course, a climate destroyer.

[A similar problem to this is that many of the economic models used by the IPCC assume BAU rates of technology improvement and energy efficiency that are very unlikely to occur absent strong government action, so they are probably overly optimistic.]


We probably need more than 14 wedges starting in 2010 to stay below 450 ppm, and we currently don’t have the political will to do more than 2 or 3. In particular, the policies needed to achieve most of the wedges are currently anathema to most conservatives, even the relatively few who actually believe the climate problem warrants strong government action.

This may depress you, but I’d rather it would motivate you.

After all, the economic cost of doing all those wedges is not high, especially compared to the incalculable cost of not stabilizing below 450 ppm. As I say in my talks, “It’s just money.” I’m not certain there is enough money in the world to bring about peace in the Middle East. But reallocating a few percent of global GDP from inefficient and polluting technologies to efficient and clean ones gets you 450 ppm or lower.

That is certainly true about switching to 100% zero-carbon electricity for the whole planet, especially using a lot of energy efficiency. That is what the McKinsey analysis has shown. That is what the IPCC has concluded. That is what the Stern Review found. Clean electricity is the linchpin, because we will almost certainly be switching from oil to electricity for most vehicular transportation this century. I will be doing a big post in a couple of weeks on a crucial zero-carbon supply side solution.

I write in my book:

Pacala and Socolow published their study to show that “humanity already possesses the fundamental scientific, technical, and industrial know-how to solve the carbon and climate problem for the next half-century.” The tragedy, then, as historians of the future will most certainly recount [if we fail to act in time], is that we ruined their world not because we lacked the knowledge or the technology to save it, but simply because we chose not to make the effort.

And then, of course, we could solve the problem the old-fashioned (WWII) way, which is the subject of Part 2.

42 Responses to Is 450 ppm (or less) politically possible? Part 1

  1. David B. Benson says:

    Er, just now need 8.5 wedges to stabilize, not just 8. Deforestration proceeds at a rapid pace…

  2. Joe says:

    Stabilize emissions, yes.

  3. jcwinnie says:

    “Mister Romm, grow up! All this talk about wedgies, given the seriousness of the subject, is just juvenile. You would think that a published author would have more aplomb than resort to sophmoric pranks as if you were writing for ‘It’s Getting Hot in Here’.”

    “Emily, Emily, Emily. He wrote wedges, not wedgies.”

    “oh… Never mind.”

    “Aunt Emily, Aunt Emily, I found it. I found it on the Internet. How to give a Princeton wedgie. See, first you…”

    “That’s nice, dear. Tell me about on our way home.”

    “Did you get him to sign his book for me?”

    “No, dear, Doctor Romm is a busy man. But, I did find out something about him… Did you know he wears lifts in his shoes?”


    “Yes. And, I think they are odor eaters because he kept going on about carbon. Now tell me what you learned on the Internet today…”

  4. AAI says:

    We are helpless against “wedges.” Too abstract.

    So, can you re-calculate what 10 wedges means in terms that every world citizen knows what he must DO? Like: move into a modest city apartment, eat meat once a month, and walk to work?

    Or how about getting the political scientists involved to say what it will take to generate the political will to come up with 10 wedges? Like: Three more Katrinas, or ten million more full-time volunteers, or 50 million more single-issue Green voters?

    Let’s get specific.

  5. Paul K says:

    The 10 year trend is a doubling of PV production every 2.5 years. Keep that up for 40 years and all electric power will be PV.

  6. elbarto says:

    The majority of the worlds population and indeed many of it’s leaders don’t have a clue when you talk in terms like PPM, GtC, radiative forcing, feedbacks, albedo etc.

    The problem with convincing people that global warming heating is going to make things FUBAR is that it is extremely nuanced – to the point where even many with a science background can’t extend their understanding beyond their own narrow fields and therefore deny the problem.

    Those that do have the understanding say to everyone else “bad things are coming, you better stop burning coal and here are some alternatives” the rest think “FUJIA (F**k you Jack, I’m alright) no bad things here I’ll keep doing what I want, thanks.”

    I can’t see any real action beyond the usual hand waving until there are a series of mega disasters. You talk about a WWII effort – but that won’t happen until bombs start dropping.

    What is happening now is creeping normalcy. It gets a little bit hotter or a little bit drier or flooding slowly increases in frequency, whatever. Folks just get used to it forget that is was cooler and wetter in the past.

    The majority of people won’t understand the implications of sustained drought until water doesn’t come out of the tap – to make the analogy, this is a bomb landing in their back yard and it might spark real action.

  7. AAI says:

    Paul K, now you’re talking. Get yourself a book deal

  8. Joe says:

    AAI: Wedges are, for better or worse, the least abstract way of explaining what must be done. I am always open to better ideas if you have one/

    Elbarto — If the majority of the worlds’ population read this blog, I’d write for them. By 2020, I think, a large fraction of Americans will know ppm and feedbacks and other things I write about. This blog if for people who want to get ahead of the curve.

    You may be right that it will take one or more catastrophes to get the change we need. Sadly, however, world can’t wait for that.

  9. Hal Levin says:

    Joe — keep writing for those who want to get ahead of the curve. What is anyone else doing reading your blog anyway? I don’t understand elbarto, jcwinnie, or AAI at all. Why are they reading your blog? And Paul K — the solar PV potential is finite, not infinite. you can’t keep growing it exponentially — even with vast improvements in conversion efficiency, the growth you describe cannot be projected indefinitely.

    BUT– as I said to you, Joe, and to everyone else at one of your public talks six months ago, we have no reason to believe that 450 ppm will yield a stable climate. In fact, what reason do we have to believe that 350 ppm will yield a stable climate? The only half-way relevant data we have on a stable climate is that 280 ppm correlated over a very long period of time with a relatively stable climate.

    Joe – Yes, you are being practical by talking about 450 ppm — “practical” as a compromise between reality and what people might be able to hear. Talking about 350 ppm and what it will take to get there will freak people out — the people who will still be reading. But, do you do those of us in your loyal following a favor by writing as though 450 ppm is a worthwhile goal? You’ve written about Hansen in a respectful way. I tend to pay close attention to what he writes and says. He is braver than most scientists. I know you read his Env Research Letters article “Scientific reticence and sea level rise” where he says most scientists are afraid to publish research results that might scare people. I don’t think Hansen would encourage us to believe that 450 ppm will give us a stable climate.

    Run, don’t walk, to the nearest exit. The calamity is upon us.

    Wedges are a nice way to visualize. You have properly identified a fundamental flaw in the assumptions – the 1.5% annual Carbon emissions growth rate rather than the current 3% rate. So, let’s get serious. We are in big trouble. When those who read your blog start criticizing the wedges concept, I can only wonder where the lifeboats are. I can’t find any on this ship, but I do have my PVs running my meter backwards when the sun shines. No meat for me. But my air travel erases all my good behavior and puts me right there on the deck counting deck chairs. Mea culpa.

  10. Paul K says:

    Hal Levin,
    Yeah, there’d probably be major workforce and production capacity issues after the sixth or seventh doubling. I have read that electricity demand will more than triple by 2050. At some point in the future almost all of our energy demands will be electrical. PV does not have to grow at my idealized rate since it is not the only alternative source. Solar energy is one wedge we definitely have.

  11. Hal Levin says:

    Paul K.,

    I love solar — it is so attractive, but…. There are real limits.

    Wind is likely to provide three to five times as much electricity as solar, according to several authoritative sources I have read lately. Check out Dan Kammen’s 2006 article in Scientific American, (Kammen, D. M. (2006) “The Rise of Renewable Energy”, Scientific American, September. 82 – 91).

    He shows growth in wind that greatly overshadows the potential of PV solar. He puts global generating capacity of solar power at 5,000 megawatts at a top efficiency of experimental solar cells at 37 percent [more than twice current efficiency — my comment, not Kammen’s] and a cost per kilowatt-hour of solar power of 20 to 25 cents.

    Compare this to his numbers for wind at 60,000 megawatts global generating capacity of wind power; 0.5 percent Fraction of U.S. electricity
    produced by wind turbines; and, 1 .9 cents tax credit for wind power, per kilowatt-hour of electricity. He writes that America has enormous wind
    energy resources, enough to generate as much as 11 trillion kilowatt-hours of electricity each year. Some of the best locations for wind turbines are the Great Plains states, the Great Lakes and the mountain ridges of the
    Rockies and the Appalachians.

    If you can’t find the Sci Am article, look at this one, Renewable Energy Policy Network for the 21st Century. Renewables 2007 – Global Status Report. Ren21, Feb 2008. See publication., available at

  12. Paul K says:

    Hal Levin,
    I’m as big on wind as I am on solar. I make a semi annual trip from Chicago to Calgary. The turbines along the way are truly beautiful. Does this make two wedges?

    Is it possible to express the reduction of a gigaton of carbon as a given amount of generating capacity?

  13. This couldn’t be clearer or more concise. A very valuable service–thanks!

  14. Joe says:

    Bill: Thanks.

    Hal: I think we need to stay below 450 this century, then go back to 350 by 2150. Hansen’s analysis does not say that won’t do the job.

  15. John McCormick says:

    Paul K;

    the simplest (not precise) way to

    [express the reduction of a gigaton of carbon as a given amount of generating capacity]

    is to use data from the EPA Quarterly emissions report which provides total kwhr generated and CO2 emissios from that unit in 2007.

    By dividing 2007 totals, I got 1.82 lb CO2/kwhr.

    Using a 90 percent on-line factor, that approximated 139,383 MW of fossil-fired generating capacity emitting about a gigaton of CO2.

    Anyone having a simpler route to get a number, have at it.

    John McCormick

  16. Joe says:


    I usually use the rule of thumb that the U.S. electric grid is about 0.6 metric tons of CO2/megaWatt-hour (that is the equivalent of one large, 30% efficient gas-fired plant).

    100% coal is about double that. The California grid is about half that.

    This is old, from DOE — but I can’t find a more recent one.

    This is a great EPA brochure with every conversion you could want:

    “Average CO2 Emissions Factor (all sources): 1,392 lbs/MWh (1,515 lbs/MWh, delivered)”

  17. john says:

    I have a problem with the wedges — I believe they grossly underestimate the potential for and importance of efficiency.

    We must aggressively work to increase the energy efficiency of the economy as an explicit first priority. Bottom line, efficiency is cheaper, the energy density of renewable systems demands a more efficient energy infrastructure, and there is more technical potential than the Princeton wedges imply.

    This has real world implications. For example, with efficiency we can cut carbon significantly right now at low or no cost; and we can reduce the amount of new renewable infrastructure we build in the future. But because we make efficiency “one solution among many,” we under-invest in efficiency based R&D and we overstate costs of achieving a given policy goal.

    The wedges make a neat organizing tool, but without some explicit policy priorities, they do as much to misinform as the do to inform.

  18. Paul K says:

    Using John McCormick’s formula (Joe’s works out the same but has an extra step from CO2 to C) a turnkey full solar wedge costs 14 trillion. Thats an awful amount of money, but it is spread out worldwide over fifty years. Hal says a full wind wedge would cost less. Is there any reason both cannot be accomplished?

  19. Paul K says:

    The less technical site link in the post lists efficiency first among wedge strategies. Each wedge will have different costs and methods of implementation.

  20. ldgussin says:

    To Hal Levin

    “the solar PV potential is finite, not infinite. you can’t keep growing it exponentially — even with vast improvements in conversion efficiency, the growth you describe cannot be projected indefinitely”

    I’d be careful making assertions that are so strongly significant, even based on the analysis of a known expert. Serious work is beginning all around and there are lots of experts and perspectives. A more recent SciAm article, for example, contained a solar call to arms.

  21. john says:

    Uhmmm. Boy am I embarassed … and after telling you, Paul, to read up on stuff before commenting.

    I was working off a very old version of the wedges which the Princeton boys gave a long, long, time ago. I see now they’ve updated it.

    In the words of Emily Latella: Never mind,

  22. Joe says:

    I tend to think S&P underestimate the efficiency potential in their wedges. But it’s hard to say how much since their baseline is unknown.

  23. Hal Levin says:

    The latest national level analysis of the electric grid is available in 2006 release of the eGRID database (2004 data), found at

    You can see the EPA’s own analysis of average emission factors at the Power Profiler site by putting in any zip code in the country. It will give you the AVERAGE ANNUAL emissions for that zip code and the national AVERAGE ANNUAL emissions. I emphasize AVERAGE ANNUAL because this number is rough and does not reflect time and weather-dependent variations in the inventory of plants on-line at various times of day, week, and year. lt lists the national average CO2 emissions as 1363 lbs/MWh. It lists the CO2 emissions for my (California) zip code as 879 lbs/MWh. California plants do not include any coal, but the Western Region interconnected grid (WERC) does, so when CA imports electricity, it may be higher than when all CA electricity comes from within the state.

    A valuable source of additional (more accurate) emissions factors for building related emissions (70% of U.S. electric consumption and ~40% of carbon emissions) is the NREL report Source Energy and Emission Factors for Energy Use in Buildings by M. Deru and P. Torcellini, NREL Technical Report 550-38617, June 2007.

    to ldgussin: can you give me the exact reference for the SciAm article you mentioned. And, is a “call to arms” the same as saying solar can do it all? If you take the solar energy that falls on certain portion of the land area and multiply it times a certain conversion efficiency, you get an estimate of the maximum potential generation. I have seen several of these kinds of estimates and been shocked at how low the potential is since I once believed it was far greater, large enough to supply all U.S. electric needs. It is far short of that if one takes a practical amount of the total land area, say 1/4 of Nevada, and uses a fairly high (by today’s standards) conversion efficiency.

    For a much more realistic look at solar, take a look at Science 22 July 2005: Vol. 309. no. 5734, pp. 548 – 551 — Is It Time to Shoot for the Sun? by Robert Service. It gives a very realistic view of the potential for solar to meet future energy needs.

  24. L.D. Gussin says:

    To Hal,

    A Solar Grand Plan: By 2050 solar power could end U.S. dependence on foreign oil and slash greenhouse gas emissions

    And for a sense of the renewable R&D work scaling up:

    My point is to support arguments and references about renewables, but not, when the stakes are so high, generalized assertions.

  25. Earl Killian says:

    Hal Levin, I’ve been used the EPA Power Profiler, but I haven’t been able to determine if the numbers are “Wells-to-Plug” numbers, or just power plant numbers. For example, for coal does it include the GHG emissions from mining and transporting the coal? From what I’ve read, they do not include this.

  26. Pangolin says:

    You can say I’m a doomer
    But I’m not the only one
    Someday you will join us
    But the world will be well-done.

    450 ppm is silliness. We are in serious ecological overshoot NOW. That is right now services the environment provided like food, water and a predictable growing season are going bye-bye.

    At this point we really are just all doing a big “hang-out and wait” and tabling a few science projects for disinterested passerby until the die-off starts and it occurs to the elites that they too could be included.

    Until then this runaway train is going to keep on accelerating.

  27. Hal Levin says:

    No, it does not include the embodied carbon emissions from mining, transport, transmission, etc. It is power plant generation only calculated, not measured, based on a heat input and a ratio or factor for each fuel as reported by the plants themselves. You can see the basis of eGRID in the users guide available at the same url I gave for eGRID

    That’s why I added the NREl reference. Be very careful using eGRID numbers as there is a lot of variability that is only revealed by very detailed examination of the database. I did that and found things that didn’t make sense. I spoke with a number of authorities and have learned of the various sources of errors or distortion. Never the less, it is a compilation of every power plant in the country.

  28. Greg N says:

    John, efficiency is not just a way to cut carbon significantly right now at low or no cost – some of it is NEGATIVE cost. I.e. it’s money saved, it makes us richer. For example, fuel-efficient vehicles are cheaper to buy and cheaper per mile. Thus, remorselessly pursuing the efficiency wedge helps pay for some of the more expensive wedges, such as solar.

  29. Mike says:

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    Gaia’s Tribute

  30. Hal, One small comment about solar panels:
    Wind turbines are not very convenient for use in an urban environment. Putting a solar panel on your roof is easy, and not overly expensive. Anyone can have one on his/her roof. What better use do you have for your roof, anyway?
    So, while they might be sub-optimal, there is no reason not to resort to solar power on small scales.

  31. Ryan Bliss says:

    I understand that your blog is aimed at those who want to stay ahead of the curve on technical issues, as I do, but could it also not address more practical matters as those mentioned by an earlier contributor: what we can do on a day-to-day basis to reduce our footprint. One thing that has frustrated me is that I haven’t seen any good metric that compares the relatively impact of different kinds of energy-use and energy-conservation behavior. Which has more impact, leaving lights on unnecessarily or driving to the grocery store for a quart of milk? Where should we put our limited personal resources, into CFLs or the extra cost of a hybrid car?

    One of your earlier discussants made an important point when he alluded to the difficulty in getting people to change their behavior. One of the best ways of doing this is through simple social pressure. Let people know what idiots you think they are for buying huge SUVs and wall-sized plasma TVs. When you see someone through away something that is recyclable, sigh loudly, go and retrieve it, and put it in the cloth bag you carry around to be put into a recycling bin later. When you are in a grocery store, go and stand in front of the bottled water and loudly proclaim — “Good God! Don’t people know that these things are made from petroleum? Better to buy a water filter and drink tap water.”

    Be a pain in the ass! It seems to be the only thing that works with most people.

  32. Ryan Bliss says:

    Oops. Meant to write “throw away”, not “through away”.

  33. Herschel Specter says:

    Contrary to what Jeffery Sachs thinks, solar power towers and corn based ethanol share something in common: they are both very expensive and have significant adverse environmental effects. Please read answer #74 in the blog questions and answers that accompany the Scientific American Jan. 2008 article “A Solar Grand Plan”. All thermal electric power plants including coal, nuclear, and solar thermal plants need a heat sink, usually water in nearby lakes, rivers and oceans. The authors of this Scientific American article acknowledged that their scheme would require 13 billion cubic meters of water per year to be evaporized in cooling towers (Likely hundreds of these in the Arizona desert). This, according to the authors, would require 275 of the world’s largest desalination plants stretching from California to Baja California to Texas, each operating at a 90% capacity factor. These desalination plants represent a huge capital invetment on their own and would also consume large amounts of energy. The authors also point out that 100 rail lines would be necessary to haul these 13 billion cubic meters great distances to the Arizona desert…more money and more energy needed. What environmentalist would want the fragile desert criss-crossed by 100 rail lines? What would be the environmental impact of releasing such a huge amount of water into the desert each year? Would the vapors from the cooling towers form clouds that blocked out the sun needed by the power tower?

    Lets not go down this path.

    Herschel Specter

  34. Joe says:

    Herschel — CSP can use air cooling.

  35. Patrick M says:

    “The problem with convincing people that global warming heating is going to make things FUBAR is that it is extremely nuanced ”

    The real problem is that the hype is wrong. The models that predicted ‘worst case’ scenarios have been proven wrong by latest satellite measurements and studies of precipation systems. Sea level rise is not accelerating. Temperature rises are not matching models. And the models that use water vapor feedback are gradually getting disproven by data. Just one example:
    Tropical cloud cover is a negative feedback in the climate system:
    “All leading climate models forecast that as the atmosphere warms there should be an increase in high altitude cirrus clouds, which would amplify any warming caused by manmade greenhouse gases,” he said. “That amplification is a positive feedback. What we found in month-to-month fluctuations of the tropical climate system was a strongly negative feedback. As the tropical atmosphere warms, cirrus clouds decrease. That allows more infrared heat to escape from the atmosphere to outer space.”

    Recent cooling trends dont disprove global warming, but they should at least make those hyping Global Warming to take notice: Natural climate change is real and the truth is almost surely not as bad as the hype pretends. Dont assume every weather event is due to man. Dont believe the lie that the ‘science is done’, its still learning. In the end, things are not even close to FUBAR, unless we destroy the environment or economy in a chimerical quest to end global warming.

  36. Patrick M says:

    “Contrary to what Jeffery Sachs thinks, solar power towers and corn based ethanol share something in common: they are both very expensive and have significant adverse environmental effects.”


    “The majority of people won’t understand the implications of sustained drought ” Models that show global warming show overall increases in precipitation. Higher CO2 levels allow plants to grow with less water requirements, ie they are more drought tolerant.

  37. Patrick M says:

    If you read the post correctly there is one firm conclusion: The only way to address Global Warming via post-fossil fuel power generation ie ” zero carbon supply side”, is through Nuclear Energy.

    The key issues are SCALABILITY and COST PER WEDGE. We didnt get that number, but some thoughts:

    1. Wind – great, but its well-known reliability issue that precludes wind from being more than 10-20% of the grid. In Texas they are finding out the truth, wind exists and people exist but they arent close to eachother. A lot of cost to build the grid. More cost to keep the grid stable with variable wind power. You need peaker plants (nat gas?) and/or capacitive power (hydro?) to buffer it.
    2. A single solar wedge costs $14 *trillion* ?!? Cant afford it. (Paul K)
    Solar PV will come down in price, but even then, solar simply will never be cost-competitive for large scale. Useful for off-grid, remote, some rooftops (maybe) maybe even 3rd world.
    This leaves aside the obvious issues of siting for solar and the fact that it will work in some locales (AZ) fine but not others (British Columbia) so well.
    3. Nuclear – any wind or solar subsidy would go 10 to 50 times farther in CO2 reductions if applied to nuclear, as the level of subsidy / GW rated is much less and the generation / rated GW is higher than any alternative.
    4. the “10 Yucca Mountains” is silly. We can have recycling of used nuclear fuel. Arent we for recycling in other areas, why not used fuel, which is 95% reusable? Do that and you still need only one small repository, and it doesnt even need to geological long-term safe. In other words, disposal is a non-issue, and if you think its enough to derail an AGW solution, then AGW must not be a serious problem to you.

    As of right now, today, nuclear is 20% of generation in the US, and 70% in France and close to that in South Korea. In short, there are countries where nuclear is a viable 70% baseload generation solution. There are no countries where any other non-fossil and non-hydro solution gets close to that. Points #1 and #2 tell you that wind and solar wont cut it to even get to 1 wedge, but even if they do, they wont scale beyond it.

    Yet when nuclear is raise, we get the scaremongering like this: “(3 nuclear plants built each week for 50 years)” … well, guess what … ANY wedge has those huge scale issues. How many thousands and thousands of wind turbines is a mere 13GW rated? well, that is only a dozen large nuclear plants, but is 13,000 or so wind turbines, consuming thousands of acres and requiring billions in transmission infrastructure to be useful. (For Texas, about $6 billion in such infrastructure on top of the turbine cost).

    400 nuclear power plants, or 20/year for 40 years is doable for the US, and they would pay for themselves as with current costs nuclear is actually the cheapest form of energy to generate. Siting is easy – just let any existing site quadruple capacity. BTW the blog earlier states “And the power isn’t cheap: 8.3 to 11.1 cents per kilo-watt hour.” This is clearly false. The actual costs are much lower in the 4-5 cents/KWh range.

    Double nuclear again, to about 800 GW rated for the US, and you will have made electricity fossil-fuel free (almost – 75% nuclear 10% wind 10% hydro+solar, 5% nat gas), and displaced most of the transportation energy (with plug-in hybrids) – All it requires is 800 nuclear power plants of 1GW+ each, at a US subsidy cost of under $100 billion *total* (over 40 years, so it is tiny really!), and a move towards wind/solar for 20% of generation.
    End result is a reduction of US emissions by 80%, reduction in oil fuel use by 2/3rds.

    If a single wedge does this … “requiring one-sixth of the world cropland.” … one has to notice that nuclear energy, with small land footprint, no emissions, is a more benign and less intrusive answer.

    It may be that environmentalists will pose the greatest threat to the environment by opposing the one real solution to Global Warming – nuclear power.

  38. Joe says:

    Oh, Bob. Please don’t throw me into that briar patch!

  39. Bob B says:

    OK–no tar either?

  40. Todd McKissick says:

    Great article, but Holy Cow. It seems all someone needs is a fact to jump on and they can claim to be an expert on a subject. I have to jump in and bring a few other facts into the limelight on this ‘nuclear is great’ commentfest.

    The article and commenters both failed to mention the labor force required to put in so many nuclear plants. Granted, many other technologies need high numbers, but there’s just not that large of a workforce that satisfies all the requirements. First, they have to be nuclear engineer level intelligence. Second they have to be trustable and stable. Third, they have to not compete with each other for the salaries and hiring bonuses that will be inevitable from such a buildup. The current buildup in 2 lousy pipelines across the midwest has driven pipe welders’ salaries into the stratosphere. One friend of mine is making $20,000/month to weld steel! I rather doubt he’s certified for anything nuclear.

    Another issue is the construction skills. As everyone knows, when you embark on a massive buildup in anything, corners get cut in the name of saving a buck. Since no one would willingly allow this, it either won’t happen or it will tremendously impact price.

    Fuel may be only a small part of the whole nuclear cost, so it’s price independent, but everything else that goes into a plant is inflating at higher than inflation rates now… and we haven’t even turned on the nuclear spiggot yet. Disregarding fuel’s price, who’s to say that the world competition won’t make the fuel scarce at any price?

    Comparing nuclear subsidies, in any form, to any single renewable (which SHOULD BE done) or to the entire renewables basket is a joke. Let’s go back and compare nuclear’s 1st commercial year to CSP’s or let’s compare CSP’s 50th year to nuclear today when they’ve each had the same development time. To see why our plants are estimated at $0.10/kwh while the rest of the world is BUILDING CSP below the $0.06/kwh (expecting it to trend down for a long time), look only to the strings attached to the subsidies.

    On CSP land use, when well-to-plug land/mwh is considered, CSP uses less land than coal, wind and even nuclear. Did someone forget to add in the mines and storage and all their externalties? CSP plants are fully recyclable and can be designed with no water cooling. Try either of those tricks with nuclear. ..or maybe the time the land is unavailable after the plant closes doesn’t count. Also consider the PERMANENT aquifer contamination of in-situ mining before you suggest it as the only other mining method to reduce land use.

    Nuclear can increase it’s scale but CSP cannot? For nuclear to do this, it had to be underscaled in the first place and now be allowed to surpass limits that were deemed unsafe in earlier times. Let’s not suddenly start using 30-40 year old equipment to 120% of the levels they have been time-tested to. CSP is easily scalable on any scale because it’s a more modular technology.

    Transmission costs are greater for CSP than nuclear? This is completely dependant on the two sites being compared. Nuclear may be more concentrated in one area so only one ‘link’ needs to be ran, but that same concentration means a guaranteed overload on any existing line. This means a new line is needed for most all new plants. CSP, on the other hand, is usually less dense (typ. 100mw to 900mw per site) and can be sited to spread the load between different lines. Also, remember this concentration applies to the security of the transmission leg as well. What happens to grid stability when someone throws a logchain over the substation feeding a 4+ GW plant?

    CSP has yet another benefit over nuclear. While it is hardly maturing yet, it is proven to be economically scalable to dual land uses like parking lots or the commercial, industrial and even the residential level. When they become more accepted, we’ll see that they offer domestic heat as a free waste byproduct. This effectively doubles their contribution for the cost of a heat exchanger. This option has the potential alone to contribute more than a full wedge as merely a spinoff.

    I think I’d vote for leaving nuclear in the basket while we concentrate on other forms of energy. I wouldn’t want to end up like France which relies on Denmark to use their excess juice at nighttime because they don’t want to turn their nukes up and down twice a day to follow peak.

  41. Dennygarden says:

    It sounds like you’re creating problems yourself by trying to solve this issue instead of looking at why their is a problem in the first place.