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Renew your energy: May 2009 Archives

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.

62% of global electricity from renewables by 2030

The UK Energy Research Centre's new study of the UK energy mix up to 2050, presents a range of possible energy scenarios with different mixes of technology, including versions with a lot of wind, some with a lot of Coal/Carbon Capture and Storage, and some with no nuclear - although most include it, in some cases, a lot. But the point is, as UKERC say, 'There are multiple potential pathways to a low-carbon economy'. It added that 'a key trade-off across the energy system is the speed of reduction in energy demand versus decarbonisation of energy supply'.

Clearly investment in energy efficiency and demand side management is going to be of central importance, but we will still need new low or zero carbon energy supplies. Accelerating renewables to avoid reliance on nuclear is a possibility, but it is seen by UKERC as quite a stretch and a viable mix would also require a contributions from fossil Carbon Capture and Storage (CCS). The dominant view remains that we will also need nuclear.

However, there are other views, some of which see renewables being able to expand very rapidly, and on a global basis. A new study by the Energy Watch Group in Germany claims that there is no need to construct new nuclear-power facilities to meet demand. It looks at two scenarios- 'high-variant' and 'low-variant'. By 2030, renewables could they say contribute about 62% to final electricity globally and about 16% to final heat in the 'High Variant', and 35% of final electricity and 10% of final heat in the Low Variant, with the overall share (heat and power) being 29% in the "High Variant" and 17% in the low Variant.

The study looks into the decrease in technology costs resulting from increased production volume, as well as the assumed individual development of the various world regions. It suggest that in the OECD region, on the High Variant, 54% of the electricity demand and 13% of the heat demand could be met from renewable sources by 2030, with the total final energy share (heat and power) being 27% (low variant: almost 17%). In the non-OECD region, renewables could supply almost 68% of electricity, and about 17% of final heat demand (low variant: 36% of electricity and 11% of heat), while the overall share of renewables rises to 30% in the high variant (low variant 18%).

Given that the present renewable energy generation capacity globally is just over 1000GW, including hydro, that is quite a stretch, but annual growth rates for wind and PV solar are around 30% and new technologies for electricity and heat production are emerging rapidly, including marine renewables like wave and tidal power, and Concentrating Solar Power.

Some of these new renewable options will take time to mature, but some are ready now for deployment- and can be installed quicky. We are talking months for wind farms, weeks for PV solar roof top devices and of course days for simple energy efficiency measures- compared to years for major nuclear plants. Of course, if the funding is available, it is also possible to install a large amount of nuclear capacity. However, one strategic issue is whether it makes sense to divert funding away from the wide variety of different types of renewables, to focus mainly on nuclear, or whether a more diverse programme would be better in terms of cost-effective carbon saving in both the short and long terms.

The study "Renewable Energy Outlook 2030" is at: http://www.energywatchgroup.org/Renewables.52+M5d637b1e38d.0.html

The UKERC report is at: http://www.ukerc.ac.uk/ResearchProgrammes/UKERC2050/UKERC 2050homepage.aspx

At the inaugural meeting of the Union for the Mediterranean recently, UK Prime Minister Gordon Brown said "...in the Mediterranean region, concentrated solar power offers the prospect of an abundant low carbon energy source. Indeed, just as Britain's North Sea could be the Gulf of the future for offshore wind, so those sunnier countries represented here could become a vital source of future global energy by harnessing the power of the sun".

How realistic is this? Dr Gregor Czisch from the University of Kassel in Germany claims that it is possible to provide a 100% renewable power supply for Europe at competitive costs if we build a trans continental supergrid using High Voltage Direct Current links. It's claimed that transmission losses with HVDC are low - about 2% per 1000 km. Then the EU could share renewable sources such as offshore wind farms in the North Sea- the EU has put the potential at 150 Giga Watt (GW) - and Concentrating Solar Power (CSP) plants in North Africa and the Middle East.

The later idea has already been floated by the DESERTEC group, and over 1GW of projects are already underway or planned in Morocco, Algeria, Egypt, Jordon, UAE and elsewhere, with, in some cases, under sea grid links to the EU also being planned. Some projects plan to have molten salt heat stores, to allow power generation to continue overnight. See http://www.desertec.org/

However, in the Czisch scenario, wind provides almost 70% of the energy, with over 1000GW of generating capacity installed, some of it in the North Sea, but some of it outside the EU, with electricity being brought in from wind projects in, for example, Kazakhstan, Russia and Southern Morocco, this wider footprint helping to compensate for local variations in wind availability. The wind resource in these regions is huge, with there being many hundreds of GWs potential in each. See: http://www.iset.uni-kassel.de/abt/w3-w/projekte/LowCostEuropElSup_revised_for_AKE_2006.pdf

The first stage might be Airtricity's plan for a Supergrid running from Spain to the Baltic Sea, linking up countries around the North Sea and beyond, with a network of offshore windfarms at nodal points in the North Sea and off the West coast of the UK and Ireland. Their initial proposal is for a £20bn 10GW wind farm project in the southern part of the North Sea, with a 5 GW HVDC link carrying power west to the U.K, and a second 5GW line running east to continental Europe, perhaps to the Netherlands.

See http://www.airtricity.com/ireland/wind_farms/supergrid/.

This idea has also been taken up by Mainstream renewables http://www.mainstreamrp.com and by Norwegian transmission company Imera Power, who have announced plans for what they call a Europgrid: www.imerapower.com/EuropaGrid/EuropaGrid.htm

The European Commission has indicated interest in this approach, allocating €150m (£139m) for early work on a possible North Sea grid, and €100m (£93m) for a link between the Ireland and Wales to help renewables generators in Ireland access the UK energy market.

The idea also got strong support from a meeting of more than 100 leading European engineers, representing 21 European countries, brought together last November under the auspices of the Royal Academy of Engineering in London to discuss Europe's renewables challenges.

Mega schemes like this do of course raise many issues. For example, about the security aspects of the supergrid and about the problems of negotiating grid link access across the whole continent. Some also worry that we would simply be switching from reliance on Middle Eastern oil and Russian gas to North African solar and eastern and southern wind. There is also the danger that EU governments might buy into this approach rather than sorting out energy problems at home- it could be used as an excuse for inaction. But, on the positive side, it could open up a vast new resource and provide income for some relatively poor areas on the periphery of the EU in the South and East- as long as the trading contracts negotiated were fair. One thing seems clear- the supergrid idea could open up not just a major new resource but also a new energy geopolitics.

A bit of a revelation emerged recently when EDF's submission to the UK governments renewable energy strategy consultation was made public. EDF, the French company that is planning to build a new fleet of nuclear plants in the UK now that it owns British Energy, said:

'As the intermittent renewable capacity approaches the Government's 32% proposed target, if wind is not to be constrained (in order to meet the renewable target), it would be necessary to attempt to constrain nuclear more than is practicable'.

EDF presumably want to build some European Pressurised -water Reactors (EPR's) but noted that, although 'EPR nuclear plant design can provide levels of flexibility that are comparable to other large thermal plant...there are constraints on this flexibility (as there are for other thermal plant). For example, the EPR can ramp up at 5% of its maximum output per minute, but this is from 25% to 100% capacity and is limited to a maximum of 2 cycles per day and 100 cycles a year. Higher levels of cycling are possible but this is limited to 60% to 100% of capacity'.

At present, when demand is low, e.g. at night in summer, fossil fuel plants are throttled back, and they are also run up to full power to meet peak demand. So, given demand changes, they may have to cycle up and down several times a day. With wind plants on the grid they may have to do this a few more times a year, when wind input is low, but that's hardly a major issue. However, if we have a lot of wind and other variable renewables on the grid, and also a lot of nuclear, then balancing the system gets harder. As EDF admit, the nuclear plants can't cycle up and down well - and there will be less fossil plant to do this. So, in the absence of major electricity storage or export facilities, when demand for energy is low but there is plenty of wind, what happens? Do we just curtail wind generation then? Or should we limit how much nuclear capacity we install?

Perhaps unsurprisingly, EDF say we will have to limit how much variable electricity generating capacity we build, although they are happier with heat supplying renewables - since they don't enter into the electricity balancing equation: 'A lower volume of intermittent renewable electricity generation and higher volume of renewable heat generation by 2020 would create a better investment climate for all low carbon technologies, including nuclear and CCS'.

Source: 'UK Renewable Energy Strategy: Analysis of Consultation Responses' Prepared for: Dept of Energy and Climate Change www.berr.gov.uk/files/file50119.pdf