Wednesday, November 28, 2007

Why nuclear power is a substantial source of greenhouse gases

Nuclear power produces roughly one quarter to one third as much carbon dioxide as the delivery of the same quantity of electricity from natural gas.

But the industry has based its comeback on the allegation that it is almost carbon-free.

James Lovelock and Sir David King have been persuaded of this and it's been used to push nuclear power to the centre of the new UK energy strategy.

However a new analysis of every stage of the process from uranium mining, plant construction, generation to reprocessing, shows conclusively that this is a myth.

This new report observes that estimates for the release of carbon dioxide from the nuclear cycle vary widely.

The U.K. Government’s 2007 Nuclear Power Consultation accepts estimates that, across its whole life-cycle, nuclear power emits between 7 and 22 g/kWh, but empirical analysis of the energy intensity and carbon emissions at each stage of the nuclear cycle produces much higher figures.

This is shown (for instance) in the Integrated Sustainability Analysis (ISA) by The University of Sydney, which concludes that the greenhouse gas (GHG) intensity of nuclear power varies within the range 10- 130≈60 g/kWh.

The estimate (below) by Storm van Leeuwen and Smith (SLS) is higher because it reflects best practice, which may be better than standard good practice, especially for waste treatment and disposal, and because the reality of errors and problems in the nuclear cycle typically raises the energy cost well beyond the planned level.

A recent example of this is the construction of the new Olkiluoto reactor in Finland, where (owing to trial and error) much of the concrete has to be re-laid, raising the carbon emissions associated with the project well beyond the intention.24 The assumed reactor lifetime is 30 fullpower years; the ore grade is 0.15 percent; at lower grades, emissions would rise sharply.

SLS covers just CO2. ISA’s estimate includes all GHG emissions from the nuclear cycle.


Construction: 12-35 CO2 g/kWh
Front end: 36 CO2 g/kWh
Back end: 17 CO2 g/kWh
Dismantling: 23-46 CO2 g/kWh
Total: 88-134 CO2 g/kWh

GHG emissions gasfired electricity generation are about 450 g/kWh.

The full report is on David Fleming's website and is a free PDF download. it contains a robust critique of the pro-environmental claims of the nuclear industry written by David Fleming, founder of the Lean Economy Connection and the originator of the concept of Tradable Energy Quotas (TEQs) (formerly known as Domestic Tradable Quotas (DTQs)).

1 comment:

Luke said...

If you read the ISA report, you will note that they completely rebutt and discredit SLS's results and analysis methodology.

Yes, there are some greenhouse gas emissions, over the whole of life cycle, associated with nuclear power - but the same goes for wind energy, geothermal, solar - every single energy technology, you name it, there are always some energy inputs, raw materials, construction of the infrastructure and so forth.

As the ISA report shows, the greenhouse gas profile of nuclear power is far, far better than any sort of fossil fuel based energy generation, and it is comparable to the "clean, green" technologies such as wind, hydro and geothermal.

Due to the very large energy inputs involved in producing the semiconductor materials for solar photovoltaics, they consistently seem to have the highest whole of life cycle greenhouse gas emissions of all these clean sustainable technologies - but still, far better than any fossil fuels.

SLS's claims about nuclear power do not stand up to any kind of peer review at all - the ISA study completely rejects them, as does the work of a group of independent physicists from the University of Melbourne, Australia: