Nuclear Energy
From Energy-Experts
Nuclear low carbon letter
Sir,
The Government has announced support for further nuclear generation as part of its strategy for low carbon, low, if any, subsidy, sustainable power generation. But, does nuclear generation fit into any of these categories?
First, how low carbon is nuclear energy? Uranium occurs mainly in low concentrations so extraction involves using a lot of energy to mine a lot of rock or dissolving out, in situ, with consequent environmental risks. At the other end of the process radioactive waste has to be stored, low level radioactive waste for shorter periods but high level waste for many tens or even hundreds of thousands of years consuming energy.
The energy used in mining and extraction occurs in other countries so logically the emissions have to be counted in those countries - the nuclear industry ignores these however. It’s all rather like buying consumer goods from China, let them emit the carbon and then blame them for building more coal fired power generation. And the waste? Well, we don’t know exactly how we are going to deal with high level waste, yet. So we can’t estimate the energy and emissions cost! It’s called low-carbon mathematics.
Second, we come to the subsidy issue. The industry states that, whilst it can raise the cost of building the new generating plant, the very high cost of long term, deep depository storage of high level waste must fall elsewhere, that is, with the Government and, ultimately, you and me. Here, we have to apply low-carbon logic. There is already a lot of dangerous waste lying around and the Government have been looking for a geologically suitable place to dig a deep depository. So that will be paid for by the Government.
If this depository is being built then it can be made large enough to store waste from new generation. A deep depository that the industry doesn’t have to pay for but it’s not a subsidy. OK so far? Good, then the next step will be to maximise the use of the depository by building more nuclear generation and that will mean less need for unsightly wind turbines – and less available money for investment in renewables. But that doesn’t matter, does it? Nuclear power is a renewable, sustainable energy provider.
Cynics believe once the huge cost of the repository is committed, the government will use this as an argument to go back on its intention to build renewable energy ie wind power offshore on the grounds that that will add yet another burden to the taxpayer.
Finally, then, we arrive at the issue of sustainability. As we mentioned at the beginning of this letter, uranium extraction involves very large scale mining and has an unfortunate history of environmental damage due to the vast amount of spoil from the mines and the escape of toxic materials into the water table. The extraction also requires the use of a lot of water; that is another environmental cost that has to be counted. Then, known, economically workable deposits of uranium are limited. Some estimates suggest that we have 70 years supply, (you need to specify more closely - is that for us, the world, what about growth - too vague) others point to new nuclear plant and suggest that 30 years is nearer the mark. Uranium occurs everywhere, even in the oceans, but the phrase to bear in mind is ‘economically workable’. And, the less uranium in the rock, the more rock that has to be mined, crushed and processed all of which consume energy.
Meanwhile, the wind goes on blowing and the sun keeps shining – for the next 5 billion years, anyway. Wind, solar and tidal generating equipment doesn’t have to be buried at the end of its life but can be recycled and, with careful recycling, the majority of the carbon emitted is that which is produced in the sun. It would only take an area about 900 miles by 900 miles of wind power to provide all the worlds electricity and is readily do able without the attendant dangers and uncertainty of nuclear - UK has the best wind regime in the world and could provide all of Europe's electricity.. concentrating solar could provide all the worlds energy with 1% of the desert areas.
Yours etc.
Roy Tindle
Comments from Professor Elliot:
From: Dave Elliott [1]
Sent: 26 January 2008 15:02
To: tyningroad@btinternet.com
Cc: dave andrews
Subject: Re: FW: Roy Tindle excellent Claverton Energy Group » Nuclear low carbon letter
I agree with the general thrust, but there are some problems. Can I pay devils advocate?
The official view is that the energy needed for fuel mining/processing is relatively small compared with what is released by reactors- the WNA say about 4% at present. The energy needed for building a repository is also a small total compared with the energy released over their lifetime from the fleet of reactors that it would serve. The energy used in running it would be even smaller -although long term. This is all sometimes relayed in terms of the cost as a pecentage of final electricity costs - put at about 2% for the getting raw ore (Yellowecake) rising to 20% for the complete front end fuel supply process (mining/processing/enrichment ) and 5% for back end (waste treatment storage) costs - and also another 5% for plant decommissioning. (These last two estimates are debatabale since they assume discounting costs over very long time scales)
The rival view is that if a large global programme of nuclear plants was attempted, it would run out of high grade uranium in a few decades time , and that the energy neeeded to process lower grade fuels would be more. Which means that, in the limit, we'd be producing more CO2 than if we just used the (mostly fossil) energy directly.
It's debateable: the official view is that more high grade ores will be found and that in any case , although getting access to lower grade ores does involve more difficult mining operations (so more energy) and more energy would be needed to concentrate them chemically, its maybe not a lot more. Meanwhile, the enrichment process is getting more efficient, and as the nuclear element (and also the renewables proportion) in the electricty sector increased, it would be zero/ low carbon energy that was used for fuel fabrication/enrichment. Finally, none of this would impact on a small UK programme- it's just a marginal increase.
Counter argument- if China and India use up all the high grade ore, we will be exposed to higher costs and fabrication energy requirements. But in terms of emissions, if by then we are getting say 50% of our energy from renewables and 20% from nuclear, and the rest from high effciency CCG T/CHP, does that matter?
Sorry, I seem to have talked myself into undermining the whole critique....
Dave Elliot
Nuclear flexibility letter
Dear Chris and Dave
Here is the paper on nuclear flexibity I mentioned. I also attach one on the nuclear poisoning effect, which means overnight shut downs are impossible.
Dave and myself wrote a short note for the Inst of Civils pointing out that the French nuclear output seems to change by about 10% during the day, whereas French power demand changes by about 30%. Most of the adaption is done via imports and exports, and by hydro. As you say Chris we need a proper evaluation of this matter
Best regards
Fred
Dear David and Others I would like to start a TECHNICALLY BASED SITE on Wikipedia which is intended to help answer the question of how the grid might be controlled if we got rid of centralised power stations. The inputs to the grid would then be wind and solar renewables, which are very intermittent, some relatively small biomass steam plant, and a bit of CHP running on biofuels. These would be supplemented by DC links to Europe. I would like to start up a discussion of the TECHNICAL ISSUES, and if there are perceived to be problems, how these might be solved. Could you possibly help with this? I am asking Dave Andrews IF DAVE WOULD SET THIS UP in wikiepdeia. If he will, I will write something spelling out what we need to know. Hope you can at some stage contribute and help keep the discussion relevant. Fred
