The Clean Energy Gap
March 15th, 2009Posted by: Roger Pielke, Jr.
In Newsweek, Sharon Begley quotes Nate Lewis of Cal Tech who has done some math:
“It’s not true that all the technologies are available and we just need the political will to deploy them,” he says. “My concern, and that of most scientists working on energy, is that we are not anywhere close to where we need to be. We are too focused on cutting emissions 20 percent by 2020—but you can always shave 20 percent off” through, say, efficiency and conservation. By focusing on easy, near-term cuts, we may miss the boat on what’s needed by 2050, when CO2 emissions will have to be 80 percent below today’s to keep atmospheric levels no higher than 450 parts per million. (We’re now at 386 ppm, compared with 280 before the Industrial Revolution.) That’s 80 percent less emissions from much greater use of energy.
Lewis’s numbers show the enormous challenge we face. The world used 14 trillion watts (14 terawatts) of power in 2006. Assuming minimal population growth (to 9 billion people), slow economic growth (1.6 percent a year, practically recession level) and—this is key—unprecedented energy efficiency (improvements of 500 percent relative to current U.S. levels, worldwide), it will use 28 terawatts in 2050. (In a business-as-usual scenario, we would need 45 terawatts.) Simple physics shows that in order to keep CO2 to 450 ppm, 26.5 of those terawatts must be zero-carbon. That’s a lot of solar, wind, hydro, biofuels and nuclear, especially since renewables kicked in a measly 0.2 terawatts in 2006 and nuclear provided 0.9 terawatts. Are you a fan of nuclear? To get 10 terawatts, less than half of what we’ll need in 2050, Lewis calculates, we’d have to build 10,000 reactors, or one every other day starting now. Do you like wind? If you use every single breeze that blows on land, you’ll get 10 or 15 terawatts. Since it’s impossible to capture all the wind, a more realistic number is 3 terawatts, or 1 million state-of-the art turbines, and even that requires storing the energy—something we don’t know how to do—for when the wind doesn’t blow. Solar? To get 10 terawatts by 2050, Lewis calculates, we’d need to cover 1 million roofs with panels every day from now until then. “It would take an army,” he says. Obama promised green jobs, but still.
March 15th, 2009 at 5:56 pm
Hooray! Those are the kind of facts that everyone needs to face. And the politicians’ job is to explain how their proposed programs will accomodate those facts. That would be the honest way to do it, anyway. But you probably won’t see these types of facts discussed by the politicians, because they are too daunting and immediately reveal the idiocy of their strategies (which probably really have nothing to do with the environment or “climate change,” anyway). They are content with slogans, magic, and “change we can all believe in.” At least some of the Cal Tech guys are thinking.
March 16th, 2009 at 2:35 am
[...] [-->] de Prometheus, de un post de Roger Pielke [...]
March 16th, 2009 at 9:33 am
“To get 10 terawatts, less than half of what we’ll need in 2050, Lewis calculates, we’d have to build 10,000 reactors, or one every other day starting now.”
I’m not a big fan of federal-government-funded technology demonstrations, but it seems like it might be worthwhile for the U.S. federal government to support building 10-100 MWe demonstration plants for a liquid fluoride thorium reactor or a traveling wave reactor.
But obviously, nothing the U.S. federal government (or private industry) is likely to do will result in the U.S. building 1000-2000 fission reactors in the next 40 years (roughly “our share” of the 10,000* worldwide).
*P.S. I was very surprised at the 10,000 number, so I did some calculations myself. The present worldwide fleet of 436 nuclear reactors has a capacity of 372 GW.
http://www.world-nuclear.org/info/inf01.html
If I use a capacity factor of 80 percent, I actually get ~15,000 reactors needed for 10 TW. Of course, the hypothetical 10,000 could be larger than the current fleet. But needless to say, even the 10,000 reactors is a staggeringly large number, and seems unlikely to even be approached.
P.P.S. I second jae’s applause; in all the pages of the IPCC AR4, is there such a basic and important analysis as was done by Nate Lewis?
March 16th, 2009 at 10:04 am
Building Nuclear Plants is one thing. Finding the fuel is another:
http://www2.canada.com/vancouversun/news/editorial/story.html?id=e7fde005-364a-4ede-9c9c-8cdfeac172ed
The [British Columbia] government has slapped a ban on exploration for uranium, outlawed any development of known deposits and imposed a “no registration reserve” to ensure no future claims include rights to the mineral.
March 16th, 2009 at 2:39 pm
Hi Raven,
You write:
“Building Nuclear Plants is one thing. Finding the fuel is another…”
The types of reactors I was proposing weren’t based on conventional uranium fuel. Instead, I was proposing:
1) A Liquid Fluoride Thorium Reactor, which is fueled with thorium:
http://thoriumenergy.blogspot.com/2007/01/uranium-vs-thorium-mining-processing.html
2) A “Traveling Wave” reactor, which is fueled with depleted uranium:
http://www.technologyreview.com/energy/22114/
Neither would require the uranium ore mining of the type in the British Columbia ban you cited. So finding fuel for the two types of reactor I suggested won’t be a problem.
Now we just need to build 5,000 each in the next 40 years!
March 17th, 2009 at 9:07 am
If the relationship between CO2 concentrations and greenhouse effect is non-linear (as Lubos Motl points out repeatedly) why is a ppm target so important, or even meaningful? Most of the effect has already occured.