environmentalresearchweb blog

« Exploring ice shelves | Main | Ups and downs of glaciers »

The Gates perception

Technology guru Bill Gates of Microsoft fame gave a sparkling presentation on energy back in February, under the title ‘Innovating to Zero’ (i.e. zero emissions).

Oddly he repeated the old saw about renewables being expensive and needing a lot of backup. Strange given that ,in California, wind power is the cheapest energy source on the grid and the main issue in the US is not so much the intermittency of wind as there often being too much wind generated electricity for the grid to handle (see my earlier blog on curtailment issues).

And even more oddly, he didn’t mention the smart supergrid idea, which could balance and manage local variations in supply and demand. You might think that would be right up his street, as someone who pioneered internet information grid systems and applications.

However his main thrust was on innovations in nuclear. He said: ‘innovation really stopped in this industry quite some ago, so the idea that there’s some good ideas laying around is not all that surprising’. He backed the so called ‘Terrapower’ idea, in which a mix of fresh uranium and depleted uranium is formed into a log type tube, buried deep in the ground and ‘burnt’ progressively, with the fission reaction running through it from one end to the other, like a candle. So it’s sometimes called a ‘travelling wave reactor’. It’s envisaged that it would take 60 years to burn through end to end , and that the waste products could just be left where they were, underground . Using depleted uranium/ spent fuel to breed more plutonium and run reactors essentially from some of the wastes from conventional nuclear plants , is hardly a new idea, but the travelling wave idea is new and untried.

What Gates now wants to see is a lot of supercomputer modelling to test if it will work. He is obviously keen. If ‘Instead of burning a part of uranium, the one percent, which is the U235, we decided, let’s burn the 99 percent, the U238’ we could “power the U.S. for hundreds of years”. And there’s more: “simply by filtering sea water in an inexpensive process, you’d have enough fuel for the entire lifetime of the rest of the planet”. For more on the Terrapower idea see its UCB originators’ website.

This says that you might need to add in some plutonium and/or thorium, basically to avoid the reaction fizzling out. Sounds a little crude and messy, leaving a wide range of wastes for future generations to deal with. And also quite hard to control, once started up. A rival approach to this mix of solids, mentioned briefly by Gates, uses liquids – actually a molten thorium flouride salt. For more on the Liquid Flouride Thorium reactor, see http://thoriumenergy.blogspot.com.

Gates evidently likes the solid idea, but the US government seems to be focussing mostly on (slightly) more conventional concepts in its ‘Next Generation Nuclear Plant’ R&D programme. The main emphasis is on an advanced High Temperature reactor with co-generation (CHP) capability, to be built at Idaho National Lab. WNN noted that ‘This was originally meant to actually operate in 2010, but its priority has fluctuated’. NGNP is part of the ‘Reactor Concepts RD&D’ programme, which will also begin working on small modular reactor concepts with a total budget of $195m.

Although the Terrapower idea may be a little off the beaten track, it’s interesting that nuclear plant designers are looking to new concepts, for example co-generation reactor systems which can be used to provide heat and well as power, possibly for industrial process heating purposes. In addition there is renewed interest in developing systems which can be used to generate hydrogen gas, either directly (by high-temperature dissociation of water), or indirectly (by electrolysis), for use as a vehicle fuel. It could be that they think that the long-term future for nuclear is not in electricity supply, but in other perhaps more lucrative and less contested markets. With wind power, and some other renewables, already looking increasingly competitive as electricity suppliers, perhaps that’s not surprising.

Even in current cost terms the conservative Nuclear Energy Agency (NEA) and the International Energy Agency (IEA) have commented in their latest joint study into Projected Costs of Generating Electricity, that “nuclear, coal, gas and, where local conditions are favourable, hydro and wind, are now fairly competitive generation technologies for baseload power generation”.

They add that “there is no technology that has a clear overall advantage globally or even regionally. Each one of these technologies has potentially decisive strengths and weaknesses”.

They conclude that “the future is likely to see healthy competition between these different technologies, competition that will be decided according to national preferences and local comparative advantages”.

It will be interesting to see how it all pans out long term, and, amongst other things, if Gates got it right. Personally, I don’t fancy a Terrapower unit in my backyard! I’d much prefer the renewable energy technologies being backed by Google, in pursuance of its $4.4 trillion “Clean Energy 2030” plan, which calls for the replacement of all coal – and oil-fired electricity generation with natural gas and renewable electricity globally, including 380 GW of wind power, 250 GW of solar power and 80 GW of geothermal power. See http://knol.google.com/k/clean-energy-2030#.

For more on renewable energy developments and policies, see www.natta-renew.org.

Posted by Dave Elliott on July 10, 2010 10:46 AM | Permalink