A field of sunflowers in front of the Areva Tricastin nuclear plant in in Bollene, in the south of France. Photograph: Fred Dufour/AFP/Getty images. Source: Guardian.co.uk

The past week saw reports of at least four of the country’s leading green activists accepting that nuclear power may have a significant role to play if we are to avoid runaway climate change. Concerns over safety issues, build-up of radioactive wastes and the proliferation of nuclear weapons were realistically balanced against the environmental impacts of burning fossil fuels such as coal, oil and gas.

Stephen Tindale, a former director of Greenpace; Lord Chris Smith of Finsbury, the chairman of the Environment Agency; Mark Lynas, author of the Royal Society’s science book of the year; and Chris Goodall, a Green Party activist and prospective parliamentary candidate, are now all lobbying in favour of nuclear options to support a renewable strategy to decarbonise the electricity system.

Nuclear power currently accounts for about a fifth of the UK’s electricity, compared with the 35% from coal and 35% from gas. It is being argued that more nuclear capacity will need to be added to replace the existing capacity, which is likely to be obsolete in around 15 years. But nuclear is not the only dwindling supply. Around 8 gigawatts – equivalent to about 6 power stations – of coal-fired generating capacity will be out of action by 2015 as Europe’s Clean Air Directive comes into force and older facilities prove uneconomic to upgrade. Taken together, the UK needs to replace a third of its electricity generating capacity in the next 15 years. Even plans for 7 gigawatts of new gas-fired capacity, expected by 2015, and another 5 gigawatts recently given the go-ahead by the Government, will not be enough as estimates put energy demand ballooning by anything up to 20% in the coming decade.

Nuclear power fits neatly with the Government energy policy goals, providing a carbon emission free source of secure energy supply – particularly important in light of recent geo-polictical tensions between Russia and Ukraine last month.

Investments are being planned by EDF (owner of British Energy), E.on and RWE Power, which are expected to create in excess of 15,000 jobs – welcomed with open arms in the current economic climate; but any planned build will only become operational by the mid 2020s at the earliest now.

George Monbiot, who has also changed his position on the nuclear argument, argues that if we want to decarbonise the UK’s energy system quicker and more cheaply, nuclear power must play a significant complementary role, alongside increased renewable energy generation, demand reduction, CHP and energy efficiency. Mark Lynas adds that nuclear power could provide a realistic solution to combating climate change and providing energy security, and as polls suggest that the public are opposing the nuclear option less and less, he calls for the Green movement to reconsider their 30 year dogma on energy generation from nuclear power.

Whilst plans for new reactors are still expected to raise face opposition, the Green movement’s acknowledgement of nuclear as the lesser of two evils will take away some of the sting. Ironically, it is the environmental agenda that made the economics of commercial nuclear expansion work. Regardless of moral reservations, the cost of nuclear power stations compared with their gas and coal-fired alternatives has always been a major factor; but the introduction of an emissions trading mechanism has forced fossil fuel plants to pay for their environmental impact, and the predictable income for nuclear plants provides much-needed clarity for private sector investors.

Whilst the safety and waste worries still remain, the arguments for and against nuclear power seemed to have changed to serve urgent targets.

Nuclear power…

*In an increasingly power-hungry world, the generation capacity of nuclear is potentially enormous

*Nuclear reactors are the best way to produce lots of electricity, reliably, with no carbon emissions

*Except for the purchase of uranium, nuclear power stations offer absolute security of supply 

However:

*Safety records may be far better than they were in the early days, but accidents can always happen

*Despite technical advances, digging a hole is still the only way to get rid of spent fuel rods

*More countries, buying more uranium, means more mining and more chance of nuclear proliferation

The UK National Grid has teamed up with 2OC, a company, which has developed “geo-pressure” technology to utilize the enormous pressure inside the UK gas pipelines, which supply UK homes.

(source: www.cryostar.com)

The first of several planned schemes will see the implementation of small turbines inside the gas network, to produce 20MW of clean energy by 2010 from the natural gas that is delivered at high pressures through the pipes.

The innovative technology will support the National Grid, which owns most of the UK’s gas pipeline, in meeting its targets of sourcing all of its internal energy use from renewable technology. It is estimated that on completion of the eight planned schemes across the UK, the combined renewable energy generation could be as much as 1GW – the equivalent a conventional coal or nuclear power station.

Andrew Mercer from 2OC explains that

“Natural gas is at far too high a pressure when it is drilled from underground reservoirs, so can’t be used safely in homes. It would just blow up your gas cooker.”

Instead, the pressure must be released at hundreds of sites across the supply network known as pressure reduction stations (PRSs). 2OC plans to build mini-power stations across these PRSs, to capture this energy, which is currently lost, to generate clean electricity.

Whilst the technology has in some form been in the spotlight before – the US considered it at some sites in the 80s – the huge associated costs have meant that it did not become more widespread. The British engineers expect to reduce costs by combining the technology with a Combined Heat and Power (CHP) unit at high efficiency. 

Mercer has also identified another use for the technology, which he calls “free cold“. Reducing the gas pressure also delivers significant temperature drops, from as much as 10C to -30C, presenting an opportunity as a potential replacement technology in refrigeration and air conditioning units. In addition there have been talks about using this technology for large scale cooling close to letdown stations, such as the EU’s proposed concentrated solar power project across Northern Africa (making the project planned for the blistering heat of the Sahara desert more feasible) and also to supply the huge cooling needs of large computer data centres.

The emergence and implementation of such innovative ideas is well received by environmentalists, particularly in light of the momentum we have built on the climate change agenda in the UK. Despite the technology being in its pilot stages in the UK, if implementation of the technology continues across the 2000+ potential sites in the UK, this would significantly reduce the UK’s dependence on foreign imports of fossil fuels to satisfy it’s ever-increasing energy consumption. Whilst enabling the UK to meet carbon reduction targets (to contribute to the mitigation of climate change) and increasing energy security, it should be noted that the technology uses the high pressure from deliveries of natural gas. If supplies are depleting, do we need to consider other ways of using this technology – assuming fewer deliveries gas? I think we do.

In terms of prices, I would expect that after initial investments to install geo-pressure technology at PRSs, the dual function (additional clean energy) which can be harnessed from deliveries of natural gas should reduce the prices of gas for end users, but whether this might be cancelled out by the increasing gas prices from overseas remains to be seem.