Sunday, March 13, 2011

Cost of nuclear power

This blog aims primarily to present information concerning the cost of solar power.  I would like today, however, to make some comments about nuclear power, particularly from an Australian perspective.  Australia is endowed with numerous energy options such as brown coal, black coal, natural gas, uranium, geothermal, solar, wind and wave power.  Any move towards nuclear fission needs to be considered in a cool, fair, honest and logical manner.

I am aware of the claims that large-scale uptake of nuclear fission will reduce CO2 emissions, thereby helping to mitigate anthropogenic global warming.  For the purpose of this discussion, let us assume those claims are correct, even though there are those who dispute them.

I am also aware of the theory of peak oil, peak coal and peak everything else.  The planet’s fossil fuel resources are finite and on current trends will not contribute much to the earth’s energy demands one hundred years from now.   [I shall defend the previous sentence in a future post.]  Moreover, if the fossil fuels are exploited to exhaustion, the near-unanimous position of climate science is that the impact on our planet will be disastrous.

My view is that nuclear fission might have a role to play in a few (very few!) places in the world.  Imagine a responsible and technologically advanced country with a large population, a small land area, situated in mid-high latitudes, perhaps landlocked or in any case with poor wind and solar resources.  Such a country needs energy.  Perhaps in the future this can be imported in the form of solar-power-by-wire or solar-derived liquid fuels?  Perhaps it might come from geothermal energy?  For such a country, I would regard nuclear fission as an option provided renewable alternatives are not available or are low-grade.  Such a country would have to deal with the known problems of nuclear fission:
·         security and avoidance of nuclear weapons proliferation,
·         the overall fuel cycle (mining, beneficiation of ore, production of 235U and fuel rods, processing of spent fuel rods, disposal of radioactive waste),
·         decommissioning of the plant,
·         long-tail risks (rare accidents that can cause major damage), and
·         capital cost, including interest during construction.

As discussed earlier on this blog, clever people devote a lot of effort to estimating the cost of power generation.  I recall the old joke about a mathematician, engineer and accountant asked to evaluate 2×2.  The mathematician had no problem giving the answer 4, exact, an integer.  The engineer checks his slide rule (OK, it’s a very old joke!), finds the answer is 3.98 and rounds it to 4.  The accountant draws the questioner aside and asks sotto voce, “what do you want the answer to be?”

And so it happens on numerous occasions.  A review is commissioned with an answer in mind, experts are appointed and lo, the right answer is duly found.  As Sir Humphrey in the TV series Yes Prime Minister would say: never hold a review unless you know what you want it to find.
In Australia, there was a big review about 5 years ago – Uranium Mining, Processing and Nuclear Energy Review (UMPNER) – which duly identified and applied appropriate assumptions to give the desired answer: a Levelised Energy Cost of AUD (2006) 40-65/MWhr.  Others disagree vehemently.  For example, long-term wind proponent Mark Diesendorf says the report (see www.foe.org.au/anti-nuclear/issues/oz/Switkowski-Infosheet-Final.doc):
“makes questionable assumptions that are highly favourable to nuclear power.  ….  The report's very low estimates of the costs of nuclear electricity are achieved by means of a magician's trick.”

Relevant to this discussion is a survey paper presented to the 2006 conference of the Australian Solar Energy Society: “Comparison of solar, nuclear and wind options for large scale implementation”, by David Mills.  Mills, a pioneer of the solar industry, concluded that in the Australian context

“ advanced solar and nuclear typical of the next decade have similar cost/efficiency and each can supply the electricity load if necessary.  Nuclear has a severe global fuel resource problem not shared by solar.  Solar has almost no fuel cost and decommissioning uncertainties while nuclear has long term back end and fuel cost uncertainties.  The author proposes … each technology must openly pay its own real costs for meeting radiological and environmental standards, security charges, insurance, fully insured waste disposal, fuel enrichment, and fully insured decommissioning.

Mills thus identifies huge issues facing nuclear fission.  In the case of the UMPNER review, the following assumptions contributed to the low Levelised Energy Cost for nuclear power:
·         a discount rate set at a lower level than that used for costing of solar plants, and
·         government guarantees on insurance, waste storage and decommissioning.
Without government guarantees, commercial insurance would not merely be much more expensive than estimated by UMPNER, it would be unobtainable.  That would rule out nuclear projects as bankable propositions.  In plain words: nuclear fission is not commercially viable without government guarantees.

Finally, what of the great hope for the future – nuclear fusion?  There are several teams around the world working on nuclear fusion, including ITER (www.iter.org).  From the ITER web site

“ITER is a large-scale scientific experiment intended to prove the viability of fusion as an energy source, and to collect the data necessary for the design and subsequent operation of the first electricity-producing fusion power plant.”

I admire the audacity and technological brilliance of projects such as ITER.  But the challenges with fusion are enormous and the technological complexity means that the power – if it comes at all – won’t be cheap. 

To me, solar and wind are the logical long-term solutions to Earth’s energy demands.

Note added one day later:

On reflection overnight, I think the above post should include more discussion on geothermal power.  Everything I’ve read indicates that geothermal power is suitable for base load generation, provided the power can be supplied to the grid.  However, the Levelised Energy Cost will be high.  In the near future, I’ll do a post on power generation from hot dry rocks (in the Australian context).

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