It's quite clear that climate change is an extremely serious problem for mankind and that we desperately need carbon-free or low-carbon energy and transport policies.

Many people, even a few who claim to be 'environmentalists', remain convinced that nuclear power is an important or even necessary way to reduce our CO 2 emissions.

However even the most cursory examination reveals big problems with that view, and when the matter is examined in detail, one wonders how on earth so many people are taken in by it.

Nuclear power stations emit no CO 2 ... ?

Let's take the most obvious issue: surely nuclear reactors don't produce CO 2 emissions? Well, true, they don't when in operation, but reactor operation is only one step in the long nuclear fuel chain.

You need to consider uranium mining, milling and concentration, nuclear fuel fabrication and U-235 enrichment, then reactor construction, spent fuel storage and construction of whatever underground nuclear fuel dump is decided upon in future: none has been built yet.

All of these steps have heavy carbon footprints, especially uranium mining, U-235 enrichment, reactor construction and deep underground excavation.

In such situations, it's normal to carry out Life Cycle Analyses (LCAs) of all the steps involved. Here the nuclear scenario would be modelled to estimate the number of tonnes of CO 2 produced from all the steps per MWh of electricity generated, and compared with similar figures from LCAs of other forms of electricity generation.

Nuclear is low-carbon, not zero-carbon

The problem is that LCAs are prone to different results because of differing assumptions used in modelling scenarios. The most reliable studies are those by independent groups who are not paid by the nuclear industry as their results are less likely to be biased towards industrial viewpoints.

In recent years, two such studies have been published - by the Öko Institut in Germany, and by Dr Storm van Leeuwen and his team in the Netherlands. Both groups found that nuclear produced less CO 2 than coal, oil or gas, but the amounts of carbon saved by nuclear power were relatively small.

Van Leeuwen estimated that nuclear produced about 1/3 as much CO 2 as a modern co-gen gas-fired plant. In other words, nuclear is a low-carbon, not a zero-carbon, source of electricity, as often touted by the Government and others.

But you may say, shouldn't we still promote nuclear, as a 2/3rds saving compared with gas is still worthwhile?

Perhaps, but there are several better ways of reducing CO 2 emissions than gas-fired stations. These include demand reduction measures via greater energy efficiency, and renewables such as biomass, wind, wave, geothermal and solar PV.

DECC refusing to accept the truth

If we're really serious about reducing CO 2 emissions, then we should be examining how much each method costs per tonne of CO 2 saved. But the Government and its nuclear acolytes seem to be avoiding this.

The reason is clear: in 2009 US energy guru Amory Lovins from the US-based Rocky Mountain Institute carried out a thorough analysis of the costs (both construction and operating) of each method of reducing CO 2 emissions.

The results were published in 'Nuclear Power: Climate Fix or Folly?'. Lovins found that in terms of $ per tonne of CO 2 saved, nuclear was among the worst methods. The best, by some margin, was energy efficiency.

I understand that a year before his report was published Lovins was invited by DECC to give a UK lecture on energy policy re the costs of reducing CO 2 emissions.

His new findings were a bolt out of the blue for DECC's nuclear diehards and Lovins was received in stony silence then quietly shown the door. We must ask: is DECC following science-based policies?

Look what telling the truth did to the SDC!

The most thorough UK examination of nuclear's potential carbon savings was by the former Sustainable Development Commission in 2006. It estimated that the CO 2 savings from a 10 GW replacement nuclear programme in the UK would only be a 4% to 8% cut in CO 2 emissions from 1990 levels, depending on assumptions.

It concluded: "Nuclear power is not the answer to tackling climate change ... ". Surprise: one of the first things the Tory-led coalition Government did when it assumed power in 2010 was to abolish the Sustainable Development Commission.

These examples of wilful disregard of available research bring to mind the infamous 'Downing Street Memo' of 2002 concerning the impending US/UK war on Iraq, in which the Director General of the MI6 stated that" ... the facts were being fixed around the policy." It seems to be happening again with nuclear power.

The cost is prohibitive

The most serious flaw in the argument that nuclear provides an answer is its prohibitively high cost. Nuclear construction costs have always been high but in recent years they have increased substantially.

The anticipated cost of Hinkley C is now £16 billion, 1.5 times the entire cost of the 2012 UK Olympic Games. This for one nuclear station which would supply less than 5% of the UK's electricity if it were ever built and operated.

As pointed out by The Economist in October 26 2013, the UK and Finland are on their own in the EU in having plans for more nuclear power.

On February 21 2014, The Spectator followed this by asking: "Why has Britain signed up for the world's most expensive power station?" and stating that MPs owed it to the taxpayer to throw out the proposed Hinkley deal.

It would be best to throw out all the Government's nuclear plans, as they clearly do not provide an answer to our climate change difficulties.

Indeed, it would be best to throw out this discredited Government altogether at the next election - and elect a Green one!

Dr Ian Fairlie is an independent consultant mainly on radiation in the environment. His previous studies, which revealed the mechanism for large observed increases in childhood leukemias near nuclear power stations throughout the world, led to this work on energy policy.

Website: www.ianfairlie.org.

This article is a shortened form of the lecture to be given by Dr Fairlie on Saturday in London - see below.

JAN: A group of mainly Japanese people in London have formed a lively organisation (Japanese Against Nuclear - JAN) who meet every week in silent vigil in front of the Japanese embassy to protest against the Japanese Government's support of nuclear power. JAN is now one of the largest anti-nuclear groups in the UK.

On Saturday July 12th, JAN is organising a lecture on why nuclear is not an answer to climate change at the School of Oriental and African Studies at lecture theatre G3 at 1.30 pm. All are welcome. For more information see http://jan-uk.jimdo.com/.