Tuesday, 20 September 2011

Thorium - Safe, Clean, Cheap Nuclear Power

Amongst Liquid Fluoride Thorium Reactor (LFTR) supporters the enthusiasm for cheap energy generated from IVth generation nuclear technology is infectious. Imagine an era of safe, clean, cheap electricity generated from thorium fuelled plants, at a fraction of the price of electricity generated from fossil fuels, and without the carbon dioxide overhead. We could look forward to hydrogen from the electrolysis of water as a fuel for vehicles. Rapidly developing countries, like China and India, could achieve their growth with clean energy, without adding to CO2 emissions. Electricity could replace oil or gas in many energy intensive industrial processes and nuclear power could be used for desalination in arid areas like the Middle East, where water is a potential source of conflict. Safer nuclear plants could be located nearer to cities and a proportion of the waste heat could be used for district heating schemes.

The First Nuclear Era – Alvin Weinberg
Modern nuclear historians, or anyone who lived through the First Nuclear Era, the period from the 1940’s to the 70’s, will remember that this was almost exactly the message promoted by nuclear energy enthusiasts like Alvin Weinberg, who was responsible for the first Molten Salt Reactor at Oak Ridge. After the Oyster Creek, New Jersey, 515 MW reactor was built by General Electric in 1969 for $129 per kW, on a fixed price contract, he looked forward to a bright nuclear future just like the one described above.

His assumption of cheap and abundant nuclear power was based on a price list for nuclear power plants issued by General Electric, and later matched by Westinghouse, Combustion and Babcock and Wilcox, which showed a rapidly reducing unit cost per kW as the size of the plant increased. According to GE’s price list, a 1000MW plant gave 10 times the power of a 100MW plant but only cost twice as much.

Oyster Creek Nuclear Plant
In 1964 Weinberg said “These prices are not flukes. Last October General Electric published a catalog listing guaranteed prices of boiling water reactors in sizes ranging from 50MW to 1,000MW..... Nuclear electricity from such reactors would be competitive with coal at around 25 cents per million Btu ($5/ton). Uranium fission is now apparently an economical alternative source of energy in large parts of the United States.”

For at least a decade orders came thick and fast and by 1972 almost 500 large nuclear reactors were either operating, under construction or on order.

The prices were taken seriously because they were published by large and experienced industrial groups and not by research organisations or consultancies and also, as Weinberg says, the nuclear enthusiasts of the time wanted to believe.

In the event these cost estimates proved to be grossly optimistic. Real costs often exceeded twice the original contract price and programmes always overran. There were also problems of reliability and, after Three Mile Island, the issue of safety became of paramount importance.

Of the 253 nuclear power reactors originally ordered in the United States from 1953 to 2008, 48 percent were cancelled, 11 percent were prematurely shut down, 14 percent experienced at least a one-year-or-more outage, and 27 percent are operating without having had a year-plus outage. Thus, only about a quarter of those ordered, or about half of those completed, are still operating and have proved relatively reliable.

Outside the U.S. the story is different and, although cost overruns have been common, nuclear projects have been more successful. Weinberg, in his book “The First Nuclear Era”, speculates that the fragmented nature of US utilities contributes to a lack of expert management and supervision when compared to the centralized structures of European countries. France, for example, currently generates about 80% of its electricity from nuclear reactors and the UK about 30%. The debate is still open in both France and the UK concerning whether to build more reactors to replace their ageing fleet, but in the U.S. the economics, taken together with the mounting opposition from pressure groups has had the result that no new nuclear power plants were built in the US for more than 30 years. (One is now under construction and seven more are planned).

I Want to Believe But...
So when I hear the claims of a new generation of cheap nuclear power I want to believe it, but I’m also cautious. It’s very difficult to estimate costs on large projects particularly if it involves innovative technology. Because you are working on something new or unique, there is little experience available and no economies of scale concerning production to apply. Perhaps, if a suitably experienced contractor were involved in the estimating process, then one might get closer to the realistic costs, but you could also end up with a repeat of General Electric’s mistakes.

In fact, realistically, even after a demonstration IVth generation Liquid Fluoride Thorium Reactor has been built and operated for a few years, we won’t know the true cost of electricity generated from them until several have been constructed and successfully operated.

But how much does electricity cost from existing nuclear plants compared to other sources? The table below is taken from an OECD report on energy costs published in 2010. (OECD/IEA NEA 2010, table 4.1.)

OECD electricity generating cost projections for year 2010 on - 10% discount rate, cents/kWh  

coal with CCS
Onshore wind
Czech R
* For China and Russia: 2.5cents is added to coal and 1.3cents to gas as carbon emission cost to enable sensible comparison with other data in those fuel/technology categories, though within those countries coal and gas will in fact be cheaper than the Table above suggests.

Nuclear Electricity is Already Cheaper
As you can see, electricity from nuclear sources is cheaper than, or competitive with, all other sources in almost every country which contributed data to the OECD 2010 study, even at a 10% capital discount rate. At a lower discount rate, where its high capital cost is less significant, it is definitely cheaper! Onshore wind power is significantly more expensive than all of the other options and, apart from hydro-electricity, renewable sources cannot secure the base load requirement. In spite of that, renewables are attracting major subsidies because in political terms they are very popular. The public has been persuaded that climate change due to man-made CO2 is real, and that nuclear power is too risky to be pursued in the long term.

To interest the utility companies it must be possible to generate electricity from LFTR’s for significantly less than the current cost per kWh for existing nuclear plants. But that will not be enough to start a new wave of technical development of LFTR technology. The technology must be demonstrated and that needs substantial funding, probably from public sources.

A Nuclear Renaissance
To overcome inertia amongst governments, and the existing nuclear industry, and to achieve acceptance of new nuclear technology, there will have to be a campaign driven on two fronts.
Firstly to persuade the public that nuclear power is necessary and
Secondly that the new technologies are safe! And not just marginally safer but really safe!

Nuclear Power is Necessary
This argument is winnable because it’s clear that nuclear power would not generate CO2 emissions. It would also not waste about two thirds to a half of its fuel input as waste heat like a fossil fuel plant does. Nuclear power is available 24h/day, which is not true for most of the renewable sources. The deployment of nuclear power also reduces the reliance on imported fossil fuels, which are often under the control of countries with unstable or capricious governments. These are all strong unarguable points.

New Nuclear Plants can be Inherently Safe
The second argument about safety is less easy to win. Those responsible for the first nuclear era were too optimistic about exposure limits and safety issues. Their designs were not safe. Subsequently, the major failures at Three Mile Island, Chernobyl and Fukushima have created so much public opposition to nuclear power that even inherently safe plant designs will struggle to find acceptance. The next generation of nuclear designers will need to be far more safety conscious and less optimistic than their forbears. They have to deliver inherently safe designs, probably over-engineered to keep the regulators satisfied. They will need to have a fully developed strategy for the wastes, including their ultimate disposal, and even then they will meet strong opposition from environmental groups.

Persuade the Public
But the real difficulty here is convincing the public that new nuclear designs can be inherently safe. Comparing already low probabilities of accidents is something the public cannot grasp. They just know that radiation is dangerous and causes cancer. They could, however, understand simple slogans like the fact that LFTR plant designs:

Cannot explode - because they are unpressurised,
Cannot overheat - because they don’t need cooling water,
Cannot meltdown - because there are no metal fuel rods,
Produce 30x less waste - because they burn thorium as a fuel.
Walk away safe - in case of power failure

Fail safe devices can also be appreciated by the public, like the plug maintained by a refrigeration system which melts on power failure and stops the nuclear reaction by dumping the liquid reactor contents, by gravity, into tanks having a non–critical configuration.

Energy for the Future
Thorium and LFTR’s could and should be a major energy source for the future, but in the West it will be fought every step of the way! After Fukushima just getting it onto the agenda of Western governments is going to be difficult. All of the various groups who support this technology need to jointly work out a public relations strategy for the next few years. How about promoting a conference just for this subject in the near future?  Invite some A-listers, some of the very wealthy, the mega-entrepreneurs and even some politicians! Someone might even come up with the funding for a sustained campaign!

Other posts about nuclear power in this blog

1 comment:

  1. I am curious. Governments around the world seem to think we have a choice. The German decision in particular astounds me with it's level of stupidity. Anyone who understands world energy resources will tell you. We have no choice. It's Thorium/nuclear or we are back to the stone age and a lot quicker than is commonly thought. World fossil fuel reserves are being consumed at an ever alarming rate. Oil in particular has maybe 40 years before complete depletion. Chaos, war and hyperinflation will set in long before then. Thorium will preserve civilisation and must be pursued BUT a world without fossil fuels is still going to be a very very different place. Oil, natural gas etc. have two irreplaceble (in a practical sense) qualities. They are a highly portable and relatively cheap form of energy and they have multiple crictical uses, fertiliser production for food is one. Electricity production only solves half the problem as a mitigation strategy. The other other half requires a serious re-think of how society is structered and current population levels. A world of 7 Billion is by current estimates 6 Billion too many.