Anyone across global warming issues is aware that we tracking a so-called ‘business as usual’ (BAU) scenario in greenhouse gas (GHG) emissions. This is not good. In 2014, Price Waterhouse Coopers found that this ‘BAU track’ leads to 4°C warming by the end of the century. If this transpires, then warming will surely continue to greater heights in the future thereby jeopardising life on Earth.
So far, despite all efforts, GHG accumulation in the atmosphere continues and looks like accelerating. Science says this portends a climate catastrophe.
Government actions have focused on adaption and mitigation and centred around; renewable energy, offsets, carbon pricing, and schemes for CO2 capture and enhanced carbon sequestration. These have been insufficient if not misdirected. We now need to look at dramatic changes in lifestyle and to non-coercive population controls as suggested by Mark Diesendorf (and others).
Renewables are a blind alley. Even when they displace fossil fuels, all renewables have worrisome levels of life-cycle CO2e emissions per kilowatt hour (KwHr). At expected levels of global energy usage of 200,000 terrawatt hours, even a single gram per KwHr sends 200 megatonnes of CO2e into the atmosphere. In the case of nuclear, according to US agencies, 13 grams CO2e are emitted per KwHr. This is far too high. It amounts to 2.6 giga tonnes (Gt) per year and more if energy consumption climbs further.
All this casts doubt on relying on renewables of any type, but nuclear, already at the high side of lifecycle emissions, has additional problems.
Nuclear plants need large flows of cooling water and exhaust heat in discharge flows; nuclear waste accumulates; the likelihood of accidents increase should nuclear installations become common and wars and terrorist events are too frequent to allow siteing of nuclear power everywhere fossil fuels are used today. The final nail in the coffin of nuclear is the fact that renewables are much cheaper than nuclear.
So it seems clear that nuclear energy gives no benefit that cannot be obtained from other renewables and incurs greater risks and greater costs. There may be an exception. Arguably, small government reactors for medical and industrial isotopes and for research represent miniscule risks even if worse-case accidents occur. It is hard to see how medical isotopes could be produced otherwise but this has no bearing on dealing with catastrophic climate change.
 Table 1, http://tinyurl.com/lifecycle-co2