Nuclear power against greenhouse gas emissions? It’s a false solution

As we have seen, the EPR’s very high cost suggests considerably higher emissions in the construction stage. So too does the fact that, over its projected 60-year lifetime, it will be using uranium from very low quality ores.

The likely delay due to the Austrian appeal against the European Commission’s decision on the EPR subsidy offers an opportunity for a full, independent and peer reviewed assessment of the environmental impact of this complex and expensive new technology.

A False Solution: Why Nuclear Power is Not “Low Carbon”, CounterPunch,  by KEITH BARNAM, 5 Feb 15 

“………..Using 0.005% ore, nuclear has higher carbon emissions than gas

Nuclear fuel preparation begins with the mining of uranium containing ores, followed by the crushing of the ore then extraction of the uranium from the powdered ore chemically. All three stages take a lot of energy, most of which comes from fossil fuels. The inescapable fact is that the lower the concentration of uranium in the ore, the higher the fossil fuel energy required to extract uranium.

Table 12 in the Berteen paper confirms the van Leeuwen result that for ore with uranium concentration around 0.01% the carbon footprint of nuclear electricity could be as high as that of electricity generation from natural gas.

This remarkable observation has been further confirmed in a report from the Austrian Institute of Ecology by Andrea Wallner and co-workers. They also point out that using ore with uranium concentration around 0.01% could result in more energy being input to prepare the fuel, build the reactor and so on, than will be generated by the reactor in its lifetime.

According to figures van Leeuwen has compiled from the WISE Uranium Project around 37% of the identified uranium reserves have an ore grade below 0.05%.

A conservative estimate for the future LCA of nuclear power for power stations intended to continue operating into the 2090s and beyond would assume the lowest uranium concentration currently in proven sources, which is 0.005%.

On the basis that the high concentration ores are the easiest to find and exploit, this low concentration is likely to be more typical of yet to be discovered deposits.

Using 0.005% concentration uranium ores, the van Leeuwen, Berteen and Wallner analyses agree a nuclear reactor will have a carbon footprint larger than a natural gas electricity generator. Also, it is unlikely to produce any net electricity over its lifecycle.

What is the carbon footprint of the ‘Third Generation’ reactor at Hinkley Point C?

All the LCAs in the published meta-reviews refer to electricity generators which have already been built. In addition to the problems described above there are at least three further difficulties in assessing the carbon footprint of third generation reactors:

* The two prototypes for the European Power Reactor (EPR) proposed for Hinkley Point are still in the construction stage and are well behind schedule. In all engineering projects the completion of a prototype results in modifications to the construction that cannot be predicted beforehand. That is the reason for building a prototype. Also, until the reactor has run for a period, it will not be clear if it will achieve its design power output and how long it will operate between refuelling. These latter two factors are important in estimating the total amount of electricity the EPR will generate in its lifetime. The carbon emissions are divided by the total amount of energy to get a carbon footprint.

* The EPR is far bigger and more complex, than any existing nuclear reactor, or indeed any electricity generating system ever built. Major design modifications have to be included to incorporate lessons learnt from the Fukushima disaster. This all means not only has the cost of the EPR risen, and will continue to rise with the prototype modifications, but also carbon emissions during the construction stage will be expected to be higher than these of current reactors.

* The intention is that fuel rods of the EPR will remain longer in the core than in today’s reactors in an attempt to reduce the cost of the electricity. This will mean that the spent fuel will be more radioactive resulting in new challenges in dismantling reactors and in dealing with the waste. Inevitably, this will lead to higher carbon footprints.

Given these three factors it is surprising that a report commissioned by the CCC in 2013 claims a carbon footprint for the EPR of 6 gCO2/kWh, comparable with the lowest two LCAs in the figure.

The report is from the company Ricardo-AEA, formed in 2012 when Ricardo acquired AEA Technology, itself a spin-out from the United Kingdom Atomic Energy Authority. Their analysis makes the astonishing assumption that both the EPRs at Hinkley Point C will operate at 1 GW above their design power for 85% of every year over a 60 year lifetime.

This is a remarkably optimistic projection that gives an unrealistically high total for electrical energy generated in a lifetime. But this is only one reason for the very low carbon footprint.

The Ricardo-AEA report quotes the spread of results from the Warner-Heath analysis. However, they compare their result with six other LCAs that all have carbon footprints below 8 gCO2/kWh. Three are from reference [5] and three are not included in the Warner-Heath study.

The report does not explain why their result differs so much from the results of the majority of the LCAs in the Warner-Heath review. Massive amounts of taxpayers’ money should not be committed to this project on the basis of such a flimsy scientific assessment of environmental impact.

An estimate of the carbon footprint of the EPR

In my book, The Burning Answer: a User’s Guide to the Solar Revolution, I discuss a simple comparison of the LCAs of the EPR and a large dam (or probably dams) producing the same amount of power.

The carbon footprint of hydropower, 10 gCO2/kWh, is much better known than nuclear. Many large dams have been constructed and uncertainties such as carbon emissions during fuel production and long term storage of waste do not apply to hydropower.

First let’s compare the construction costs. The cost of building the first 1.6 GW EPR at Hinkley Point is around five times higher than the cost of building the hydropower dams which provide the same electrical power. This higher price suggests higher carbon emissions.

The EPR price reflects the high cost of more sophisticated nuclear engineering, manufacturing and transporting a steel pressure vessel, expensive high precision nuclear components, steam generators and safety systems.

Many of these additional costs for the nuclear option result from burning fossil fuels directly in manufacture or transport or in the generation of electricity in all stages of construction. The fact that the EPR costs five times the hydropower option suggests the construction could result in up to five times larger carbon emissions than dams that give the same power.

This approach was first suggested by Hans Bethe, the physics Nobel Prize laureate, in the 1960s, and has been widely used by both companies and governments as a first estimate of their carbon footprints.

Assuming the reactor and the dams have the same lifetimes, and generate for the same time each year, the carbon footprint in grams of CO2 for each kWh of energy could be up to five times higher for the EPR than for hydropower: hence around 50 gCO2/kWh.

But note: this rough estimate is only for the carbon dioxide emitted during construction. It ignores the carbon emitted during the problematic three nuclear stages, fuel production, dismantling and waste disposal.

This simple argument suggests to me that – as for the first and second generation – there is as yet no solid scientific evidence that the carbon footprint for the EPR will be below the CCC recommendation of 50 gCO2/kWh. Indeed once the additional carbon emissions are taken into account, it’s certain to be considerably above that figure.

So the claim that the carbon footprint of the EPRs planned for Hinkley C will be as low as 6 gCO2/kWh, less even than hydropower – as claimed in the Ricardo-AEA report commissioned by the CCC – is wholly incredible.

What should be done now?

The UK government should follow good engineering and good investment practice and undertake full due diligence before signing a contract to subsidise the EPR. This should include a complete and thorough LCA of greenhouse gas emissions including data on the performance of a working prototype.

The likely Austrian appeal against the European Commission’s approval of the subsidy may delay the contract signing beyond the 2016 completion date for the EPR. In any case, it is extremely bad engineering and bad investment practice to sign a contract before a prototype operates. The LCA should be subject to thorough review by independent experts as is the case for technical due diligence for commercial investment.

The Hinkley C project is surely Britain’s largest and most expensive electricity generating project. It is certainly the most complex. At the present time the UK government is keen to sign a contract with French and Chinese companies, many of which are owned by their governments, to build the project.

The contract will commit the UK public to paying heavy subsidies and may be signed before it is known if the prototype works or what its environmental impact will be. This would be engineering, investment and, possibly, political stupidity.

Conclusions

There is no consensus in the scientific literature as to the carbon footprint of existing nuclear reactors. I have more confidence in the six highest LCAs because two of them have been independently re-assessed and – in contrast to the two lowest LCAs – the higher analyses have taken realistic account of the uncertainties in the three most problematic parts of the nuclear life cycle.

As all six are either above, or have error bars that reach above, the CCC’s 2030 threshold of 50 gCO2/kWh, the balance of the evidence of the six most robust LCAs is that the carbon footprint of nuclear power is above the CCC’s recommended limit.

And of course these figures apply to existing nuclear power stations, not the EPR design planned for Hinkley C. As we have seen, the EPR’s very high cost suggests considerably higher emissions in the construction stage. So too does the fact that, over its projected 60-year lifetime, it will be using uranium from very low quality ores.

The likely delay due to the Austrian appeal against the European Commission’s decision on the EPR subsidy offers an opportunity for a full, independent and peer reviewed assessment of the environmental impact of this complex and expensive new technology.

Keith Barnham is Emeritus Professor of Physics at Imperial College London, where his group developed a third generation solar cell with three times the efficiency of current rooftop PV. He co-authored the only published study of plutonium production in UK civil reactors. He is author of The Burning Answer: a User’s Guide to the Solar Revolution, published by Weidenfeld and Nicolson. ISBN 9780297869634.

The author wishes to acknowledge the valuable assistance of Neal Powell, Benjamin Sovacool and Storm van Leeuwen.

References…… http://www.counterpunch.org/2015/02/05/why-nuclear-power-is-not-low-carbon/

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