Nuclear - or solar?

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Nuclear - or solar?

There is reputedly a nuclear renaissance underway, with new reactor technology providing some of the impetus. However, problems seem to have emerged for one of the new reactor types that have been developed- the European Pressurised Reactor (EPR). The first two EPRs, being built in Finland and France, are both behind schedule and over budget. Olkiluoto 3 in Finland, now over three years behind schedule, was originally budgeted at €3bn, but is now expected to cost at least €4.5bn.The follow-up French EPR at Flamanville is around nine months behind schedule, with the cost of power now being expected to be around 20% more than planned- around 55 euros a megawatt hour, instead of the 46 euros announced when the project was launched in May 2006.

In the UK, much of the running is being made by the French company EDF, who have taken over British Energy and have talked of building possibly 4 new plants here, presumably EPRs. They have claimed that they will not need subsisdies, but on May 26 2009 Vincent de Rivaz, chief executive of the UK subsidiary of EDF, told the Financial Times that a “level playing field” had to be created, suggesting that the government needed to put a guaranteed floor under the price of carbon permits in the EU’s emissions trading scheme. He said “We have a final investment decision to make in 2011 and, for that decision to give the go-ahead, the conditions need to be right,” adding that “We will not deliver decarbonised electricity without the right signal from carbon prices.”

Meanwhile, South African power company Eskom has decided not to press ahead with a planned nuclear build programme, with an EPR being one option, saying the costs were too high. This means the only current nuclear build programme underway in South Africa is the experimental 165MW Pebble Bed Modular Reactor (PBMR) and costs for that have risen significantly. In 1999, construction costs were budgeted at R2 billion rand (£200m). By 2005, they had risen by a factor of seven, to R14 billion (£1,400m), not including decommissioning and waste processing.

Interestingly, Eskom is seeking finance of R5 billion (£500m) to build a 100MW concentrating solar power (CSP) plant in the Northern Cape. CSP, which use light focussing mirrors, troughs or dishes to generate steam for a turbine, is still expensive, but even so, on the basis of the figures above, the PMBR will cost 1.7 times more per MW installed. Plus of course, once built, fuel cycle costs- which don’t exist for CSP.

Around the world, CSP seems to be catching on. There are large projects operating in Spain and the USA and more are planned there and in Egypt, Algeria, Morocco, the UAE Iran, Israel and Jordan- in all there is 1.2 GW under construction.According to estimates in a CSP Today.com overview of new CSP in Europe, North Africa and the Middle East, last year more than 3000 MW of new CSP projects had been announced.

The US has 75 MW of CSP under construction, and 8.5 GW scheduled for installation by 2014, while the American Solar Energy Society claims that in theory CSP plants in the SW states of the USA ‘could provide nearly 7,000 GW of capacity, or about seven times the current total U.S.electric capacity’. Globally, CSP could supply7% of electricity by 2030, and up to 25% by 2050, according to a report by the IEA SolarPACES group, Greenpeace, and the European Solar Thermal Electricity Association

That would of course take massive investment, but current investment this year was over 2 billion euros worldwide and technology advances are being made. Some of the 480MW of projects already in place globally are hybrid solar-gas plants, with gas providing the steam overnight, but some are now making use of molten salt heat stores to produce solar heat around the clock. There are also plans to transmit power from CSP plants in N Africa by High Voltage DC undersea links to Europe. That of course adds to the cost. Even so, CSP solar looks like it could be an interesting new renewable option.

Indirect solar, in the form of wind energy, is still the most economic of the major new renewables, with over 120 GW now in place globally, and biomass represents a very large solar-derived energy source, but the prospects for direct solar energy are also looking good. In addition to the new CSP projects, there is around 120GW(th) of solar heat producing capacity installed at present worldwide and over 10GW of solar PV electricity generation capacity.

There is clearly some way to go before these and other new renewables can rival nuclear, which has around 372GW of operating capacity. However, if the 760 GW or so of existing hydro capacity is included, along with contributions from geothermal plants and modern biomass/waste powered plants, then despite their generally lower capacity factors (e.g. around 20-30% for wind and CSP without storage, and 40-50% for large hydro, compared to 70-80% for nuclear), the renewables overall would, even now, seem to be able to offer a similar level of output. And more is coming on line rapidly.

By contrast, although some new plants are under construction or planned, the nuclear contribution fell over the last year to about 14% of global electricity generation, due in part to the extended shutdown at Japan’s Kashiwazaki Kariwa plant. Six of the site’s seven reactors have been out of action since the Niigata Chuetsu offshore earthquake in July 2007. The seventh unit restarted this month, but it is still not clear when the others will follow.

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