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Saturday, January 12, 2013

62. A 'Nucleocultural' Energy Regime?



No power is more expensive than no power.
(Homi Bhabha)

Can nuclear energy be the engine for the next energy regime, after the current carbocultural energy regime runs out its course? At present we are facing a major carbon-footprint problem which will only become worse with time. Nuclear energy is attractive at least on this count; there is little emission of carbon dioxide in the entire nuclear cycle from ore mining to radioactive-waste management. And if nuclear fusion also becomes available as a source of power (at present only nuclear fission is being exploited for generation of electric power), there is the possibility of a near-perennial solution of all our power-production woes.


How much per capita production of electric power should we humans aim for? The United Nations has worked out the 'Human Development Index' (HDI) as a measure of the quality of life. And an interesting observation is that the HDI does not go on increasing indefinitely as a population consumes more and more electricity. There is a saturation effect, although initially the HDI does increase with increasing consumption of power. Beyond ~9000 kWh per person per year there is no significant increase in the HDI.


Norway, Canada, USA, Australia and Argentina have an HDI of ~0.95 (the highest), and their power consumption ranges from ~25000 to ~2500 kWh per person per year. Some of the lowest HDIs are: 0.31 (Niger), 0.42 (Zambia), 0.55 (Pakistan), and 0.62 (India). The power consumption of these countries varies from ~0 (Niger) to ~700 kWh per person per year. For China the HDI is ~0.78, and the per capita power consumption is ~1500 kWh per annum.

The world average for the HDI is 0.741, and that for power consumption is 2490 kWh per person per year. Beyond ~6500 kWh per person per year there is no substantial increase in the HDI.

Much of the information I am giving here is from an article by an ex-Chairman (Dr. Anil Kakodkar) of the Atomic Energy Commission of India, published in the April 2012 issue of Physics News (India). He suggests that India should aim for 5000 kWh per person per year. If India manages to stabilize its population at 1.6 billion, it would then need ~8 trillion kWh of electric power, a full 40% of the global total generation of electricity.

Every year the world emits ~30 billion tons of carbon dioxide, of which the Indian contribution at present is only ~1.7 billion tons. The present power production in India is ~0.8 trillion kWh, so India would produce 17 billion tons of carbon dioxide per annum if the power production goes up to 8 trillion kWh. The consequent effect on climate change would be unacceptably high unless we harness nuclear energy (and also solar energy for local uses) in a big way.

India has a three-stage nuclear-fission programme, which has been formulated keeping in mind the large amounts of thorium available indigenously. Thorium is a 'fertile' material, and not a 'fissile' material. This means that it has to undergo 'breeding' in a reactor to become a fissile material usable as a fuel for producing nuclear power.

Stage 1, which is currently underway, uses uranium in thermal nuclear reactors. But such reactors are not very efficient for breeding fissile materials. By contrast, a 'fast breeder reactor' can produce much more fissile material than it consumes. Such reactors comprise Stage 2 of the Indian nuclear programme. This is how large amounts of thorium will be converted to fissile material, namely U233. The first such 500 MWe commercial fast-breeder reactor is about to be commissioned.

Indian reactors in Stage 3 will use U233 as the fuel, and will be able to meet the Indian power needs for the next 200 years.

The opposition to nuclear programmes comes from the public perception of short-term and long-term safety problems, with Fukushima fresh in the public memory. But here are some facts:

1. The death rate per TWh from the various energy-production options is the least for nuclear energy.

2. No correlation has been established between the incidence of cancer and low level radiation. In the nuclear industry there is followed a principle called the 'linear no threshold principle'. It is a conservatively formulated principle which deliberately ignores the fact that for low radiation levels the consequences no longer vary linearly with level of radiation. In case of a nuclear accident, one calculates the area affected by the release of radioactivity and the number of people living in that area. If the number of people is large, the calculated consequences work out to be huge, even for very low levels of radiation. This is what the anti-nuclear lobby exploits, ignoring the fact that the linear correlation is NOT applicable for low levels of radiation. According to the American Health Physics Association, there is no risk to human life up to 100,000 microSv life-time dose of natural radiation.

3. In the Fukushima episode, there was no fatality due to exposure to radiation. No worker was exposed to a dose of radiation with a significant probability for a serious health consequence. It was the tsunami that killed more than 13000 people, with another 14000 missing.

4. To address the risk of diversion of nuclear material, 4th generation nuclear reactors are being designed which will provide cost-effective, clean, and reliable energy with minimal risk of proliferation. The Advanced Heavy Water Reactor (AHWR) designed by India is an example of that.



I end by quoting from Dr. Kakodkar's article, mentioned above:

Nuclear energy provides 16% of the world's electricity today and it has been supplied for decades in a cost effective manner. Despite Fukushima, or Chernobyl or Three Mile Island, the real risk of nuclear energy is the lowest among various other forms of energy in commercial use. The advantage of nuclear would be seen to be much greater if one factors in additional risks associated with the predicted consequences of climate change as a result of use of fossil energy in business as usual manner. That could well be a bigger killer than several atom bombs together.
But the collective human psyche is not exactly famous for rational thinking. Should we look for options other than predominantly nuclear? In the next post I shall describe one such scenario.