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Renew your energy: June 2010 Archives

In 2006 the Centre for Alternative Technology (CAT) in Wales produced a very radical 'Zero-carbon Britain' scenario, which envisaged UK fossil fuel consumption being cut down to almost zero by 2027, and renewables being powered up to meet almost 100% of UK electricity, with 50% of that from wind, supplying 474 TWh p.a., while overall energy demand was cut by a half. Although welcomed as a visionary exercise setting the outer limits of what might be conceived, as a practical proposal it was met with more or less polite disbelief from most of the energy-policy fraternity.

Four years on, things have changed. The government is now proposing that we get 32% of our electricity from renewables by 2020 – much of it from offshore wind, with up to 40 GW planned. Still a long way short of the CAT's 2006 vision for 2027, but this is now beginning to look more credible. So it will be interesting to see what the reactions are to the CAT's revised 'Zero-carbon Britain' scenario, running now to 2030, which was launched recently.

It is still very radical, but is much more convincing, in part because there is now more solid data to call on, including the UKERC's reports and David MacKay's book, which the CAT relies on heavily.

The new version's basic plan is similar to their earlier one – a massive 55% cut in energy use and massive reliance on renewable electricity, from offshore wind especially, which, as before, supplies much of the transport energy (via overnight battery charging of electric cars) and heating demand (via heat pumps). But the contribution envisaged from wind is now even larger – 690 TWh p.a. mostly from around 195 GW offshore. And also 75.5 TWh from wave and tidal projects, plus 50 TWh (thermal and electricity) from biomass CHP. Some biofuels are used for transport (112.6 TWh), but 65.8 TWh of renewable electricity, plus 99.8 TWh of hydrogen derived from renewable sources, is also used for transport. Demand for domestic heat is met via heat pumps (61.2 TWh of electricity delivering 148.2 TWh) and 24 TWh of solar heat, plus the biomass CHP heat input, along with 104.6 TWh of direct biomass heat – all of course being used in well insulated homes with lower heat needs.

Interestingly, the CAT does not include geological Carbon Capture and Storage (CCS), which it sees as expensive, not very efficient and still in the development stage. Instead it restricts itself to 'the proven technology of land-based Carbon Capture & Storage using natural photosynthesis' and focuses on below-ground storage in soils, above-ground in-situ storage as biomass, and long-life storage in biomass products and in engineered silos. Indeed much of the very interesting section on land use focuses on sequestration, and also on reducing carbon and other emissions from producing (and importing) food – we move away from meat (beef) and dairy (milk). That could be wise, but hard. Possibly even harder, we move away from flying and towards public transport.

On grid balancing, they say that the new offshore wind farms 'will be commissioned at dispersed locations around the country and the back-up generation consisting of biogas, biomass, hydro and imports will help to manage the remaining variability. However, all of this will need to be complemented with a large increase in the management of electricity demand. Both the supply and demand sides of the equation are malleable and both will require intensive management'.

In particular they look to demand side management i.e. rescheduling some loads via smart meters when energy is most abundant, and therefore cheaper, for the consumer. They mention electric storage radiators, heat pumps, electric vehicles, air conditioners, washing machines, fridges, freezers, dish-washers and tumble dryers. Not all on that list will be popular choices!

Another grid balancing option, in addition to pumped storage and gas turbine back-ups, is the supergrid – but while some imports of green power are envisaged from the EU (it seems about 14 TWh p.a), the CAT does not see us importing energy from Concentrated Solar Power projects in North Africa by 2030: it argues that 'security of supply is important, and depending heavily on another region of the world therefore needs to be considered carefully in geopolitical, ethical and financial terms'. And, overall. energy exports (174 TWh p.a) will heavily outweigh imports. In general, reflecting its emphasis on localisation and decentralisation, imports are seen as bad – reducing UK reliance on overseas imports of energy and also food and other consumer items, is seen as a key part in reducing our emissions.

To make it all happen the CAT looks to various changes to the support and pricing system. It backs Feed-In Tariffs, but it says 'to more effectively balance the grid, the government should implement a form of locationally differentiated pricing for new generators within distribution networks to signal the best places to build new capacity, such as at the ends of constrained distribution networks'.

That's debatable – differentiated charging by area will mean high charges for some of the largest renewable generators (e.g. in Scotland). The Scottish government has noted that, under the current system, a power station in central Scotland pays £25 m more for transmission than a similar facility in Yorkshire. The government has said that the current system reflects the cost, and raises revenue for grid improvement. Similarly, the CAT sees it as necessary for an 'interim period, until the transmission network is reinforced'. But basically it sees local micro-grids as a key to a more localised future.

It's certainly an ambitious vision, developing on the new-energy agenda that seems to be emerging in radical ways. And of course with no new nuclear.

What would it cost? The CAT says: 'Offshore wind is a central part, if not the core part, of building a green, sustainable economy in Britain. This transition and development of new industry requires investment. The peak of £30 bn in 2022 represents only 2.2% of the UK's 2008 GDP and delivers an electricity generation system, which has very low fuel costs. If we were instead to generate the proposed output of 599 TWh in 2030 from 50% coal and 50% gas, it would incur a fuel cost of approximately £13.5 bn per annum at 2008 prices. In reality these fuel costs are likely to rise far higher by 2030 and would constitute an enormous unnecessary expense to the general public'. The CAT also notes that, at a price of 4p/kWh, the proposed 159.34 TWh of net exports is worth £6.37 bn and it says that 'this annual income could really help the UK balance of payments'.

The CAT admits: 'The construction of wind turbines at the proposed rate would obviously require a considerable amount of materials.' And, based on 45% being steel and 55% concrete, that is 16.2 million tonnes of steel and 19.8 million tonnes of concrete used over twenty years, 'the embodied energy of steel and concrete for this total build would be 115 TWh'. However, the CAT says that there is a high-energy return on energy invested for wind (it quotes a 28:1 ratio), so the investment is worth it.

You can access the CAT report at

A YouGov poll for EDF Energy in May found that 64% of over 4000 people asked across the UK now say nuclear is needed as part of a balanced energy mix for the UK, compared to 65% last year, 62% in 2008 and 59% in 2007. The regional picture varies: 69% of people in the East of England felt nuclear was needed as part of a balanced mix. In the South West 65% agreed. But it fell to 61% in Scotland.

Interestingly, among Lib Dem supporters, 58% nationally agreed that 'nuclear energy has disadvantages, but the country needs it to be part of the energy balance,' with 47% backing (32% opposing) new nuclear. 63% of Tory and 50% of Labour voters also backed new nuclear.

However, you have to careful with statistics: net support (% for, less % against) nationally was only16% for nuclear, though it was an increase on the 14% recorded in 2009. It is also instructive to look at support for other options: net support for renewables was 61%, although that had decreased slightly from the 64% in 2009 The levels of support also depend on what question you ask: a YouGov poll of over 2000 people for Greenpeace, in late April/early May found that only 34% felt that the government should increase the amount of public money it spends on nuclear power, while the figure rose to 58% for wind power.

This seems to reflect the national view – nuclear may have to be accepted, but renewables are more popular. For example, in the YouGov poll for EDF, in Scotland , which is aiming to get 50% of its electricity from renewables by 2020, only 47% of Scots supported replacing existing nuclear plants when they closed, while, 80% backed offshore wind farms and 69% were in favour of onshore turbines. 74% of Scots said their impression of wind farms was favourable, compared to 43% for nuclear.

Cost was a key issue for many people in the YouGov poll for Greenpeace – 41% felt that nuclear power was expensive, and had never been built on time and will end up requiring taxpayers' money, while 23% disagreed, and there were 36% who didn't know. An even more crucial issue for many people is the absence so far of an agreed solution on waste 65% felt that an agreed solution on waste was necessary before new power stations were built. Only 23% didn't mind and 12% didn't know.

This continued concern is perhaps surprising given that the industry keeps saying that the proposed new reactors will produce less waste. However the reliability of this message has been challenged. The spent fuel from the proposed new reactors is not going to be reprocessed. That means it will contain all the plutonium and other isotopes created in the fission process. So in effect there will be more high-level waste than at present – when the plutonium extracted. And the aim is to keep the spent fuel stored at reactor sites for up to 150 years. Moreover the plan seems to be to try to improve the economics of the reactors, by using more highly enriched fuel and to go for high fuel burn-up, with longer residence times in the reactor. The resultant spent fuel will therefore be around 50% more radioactive. Not something you'd like on your doorstep, as local anti-nuclear groups have made clear. The earliest date for the creation of a final home for high-level waste, assuming a community can be found that is willing to take it (with suitable cash inducements), is 2040.

Abandoning reprocessing does mean that there will be less intermediate and low-level waste from the new reactors, but then we are not short of that, from the existing reactor fleet – and from the ongoing process of decommissioning. This is already creating problems. The low-level nuclear waste 'repository' at Drigg is almost full, with their being no room from, for example, for wastes from the old Chapel Cross Magnox complex in Scotland, which is being decommissioned. The plan is it seems to dump the resultant contaminated soil and rubble in Cumbria, with 12 lorries a day destined for the former open-cast coal mine at Keekle Head, near to the source of the river Keekle. However, it's been claimed by local opponents that he radioactive wastes could leach into the land. Similar moves to try to dump low level wastes around the country (e.g. in land-fill sites) have been opposed by local groups.

For more information, visit Radiation Free Lakeland.

Opposition to nuclear in the UK has not reached anything like the levels seen in Germany, where more than 140,000 people took to the streets in April to commemorate the catastrophe of Chernobyl, and demand an immediate end to nuclear power. 120,000 people formed a 75-mile human chain that stretched from the nuclear power plant in Kruemmel through the city of Hamburg along the Elbe River to the nuclear plant in Brunsbuettel, on the North Sea coast. Meanwhile, in southern Germany, 17,000–20,000 people surrounded the reactor of Biblis and in Ahaus 7,000 protested at the interim radioactive waste storage facility. The scale of the protest were seen as indicating significant opposition to Chancellor Angela Merkel's proposal to revoke a law that would shut down nuclear plants by 2020 – the numbers exceeded all expectations, on scale comparable to the mass anti-nuclear movements of the 1970s/1980s.

Back in the UK, local groups and national campaign organisations like Friends of the Earth and Greenpeace apart, the main signs of opposition have come form the Lib Dems, the Green Party and the SNP. And with an anti-nuclear Lib Dem as Secretary of State for Energy and Climate Change, the issue has moved up the political agenda.

Overall there is clearly still a sizeable minority in the UK and elsewhere who are concerned about the nuclear option. A Eurobarometer survey of 26,470 EU citizens across all EU states, carried out in September and October 2009. It focused on safety issues and found that while 59% of those surveyed felt that nuclear plants can be operated safely, most believed that the risks related to nuclear energy are underestimated, with a lack of security against terrorist attacks on power plants and the disposal and management of radioactive waste identified as the major dangers. So 82% agreed that it would be useful for nuclear waste management to be regulated at the European level. But while in a 2006 poll, 62% thought that nuclear could help combat climate change, only 46% now did. That's a significant change, in that concerns about climate change are one of the main drivers of support for nuclear. Even so, overall 17% of those asked felt that nuclear's share of electricity generation should be increased (up from 14% in a similar poll in 2006), while 39% (up from 34%) felt its share should be maintained. But 34% felt its share should be reduced (down from 39% in 2006).

Commenting on the survey, the European nuclear industry trade association Foratom, said: 'Experience shows that the more citizens know about nuclear energy, the more they are in favour of it.' That's not immediately obvious. As in Germany and elsewhere, in the UK a lot of the opposition has been led by local groups near the planned plants at existing sites, like SHE at Hinkley, and BANNG at Bradwell. CANE at Sizewell, who are more than familiar with what nuclear power has to offer. It will be interesting to see if their disaffection spreads.

A wide range of local and national groups are campaigning on specific issue and against nuclear in general:

For pro-nuclear lobby views, visit:

**Not Wales, or Scotland…they want renewables**

The Welsh Assembly Government's new Energy Policy Statement 'A Low Carbon Revolution', sets out an approach to accelerating the transition to a low carbon energy economy in Wales, focusing on efficiency measures and the use of indigenous renewable forms of energy such as marine, wind, solar and biomass. It claims that by 2025 around 40% of electricity in Wales could come from marine sources and a third from wind.

In addition to local community-level micro-generation projects, it proposes the use of offshore wind around the coast of Wales in order to deliver a 15 kWh/d/p (per day per person) of capacity by 2015/16 and to capture at least 10% (8 kWh/d/p) of the potential tidal stream and wave energy off the Welsh coastline by 2025, and it wants onshore wind to deliver 4.5 kWh/d/p of installed onshore wind generation capacity by 2015/2017. It will back small-scale hydro and geothermal schemes, where they are environmentally acceptable, in order to generate at least 1 kWh/d/p, and wants bioenergy/waste to deliver up to 6 kWh/d/p of electricity by 2020 – 50% indigenous/50% imported – also offering an additional heat potential of 2–2.5 kWh/d/p.

It says that 'any new fossil fuel plants should be carbon capture ready with fully developed plans for carbon capture and storage; and that these plants maximise efficiency through use of waste heat and co-firing where appropriate' but adds 'we remain of the view that the high level of interest in exploiting the huge potential for renewable energy reduces the need for other, more hazardous, forms of low-carbon energy and obviates the need for new nuclear power stations'.;jsessionid=xhyPLpMdtJ7TT1gcXtkhq87y4tyk9f9y2QBvDh8Rjj9bGn0ghhqy!-1820637139?lang=en

That puts Wales in the almost the same situation as Scotland. Although its renewable resource may not be as large as that in Scotland, Wales sees no need to develop new nuclear plants.

Scotland of course has been making that case for some while, with the ruling Scottish National Party being implacable opposed to new nuclear, much to the annoyance of the Westminster government. Equally resolutely, the Scottish government has backed renewables. As a result, Scotland now generates around 30% of its electricity demand from renewables, with the contribution from on-land wind (with over 2GW of capacity in place) having overtaken that from hydro, and by 2020 the intention is to reach at least 50%, with wave and tidal power making major contributions.

Scotland's marine renewable resource is certainly very large, SNP leader Alex Salmond described Pentland firth as making Scotland 'the Saudi Arabia of marine energy'. 1.2GW of wave and tidal current projects has now got the go ahead in Pentland Firth and Orkney waters and the potential has been put at up to 20GW or more.

The Scottish government has been pushing ahead, most recently via a new £12m Wave and Tidal Energy: Research, Development and Demonstration Support fund – to be known as WATERS – to support the testing of new wave and tidal prototypes in the seas around Scotland. It also has a revenue support system offering five Renewables Obligation Certificates (ROCs) for every MWh of power produced and tidal systems and three ROCs per MWh for wave systems – well in excess of the UK national support system, which only offers 2ROCs/MWh for wave and tidal current projects. In addition, the £10m Saltire Prize, funded by the Scottish government, aims to accelerate the development of commercially viable marine energy. The winning entry, to be chosen in 2017, will be required to harness tides or waves to generate 100MW of electricity over a two-year trial undertaken at some point between 2012 and 2017.

However, Cabinet Secretary for Finance and Sustainable Growth John Swinney has noted that electricity from wind and marine energy was not the only option. Scotland's new Renewable Action Plan also focuses on renewable heat and he says: 'Heat from renewables needs to rise tenfold in the next decade and we will investigate all options to boost the sector, from large scale industrial plants, more energy from biomass and waste, through to microgeneration. We will support growth in, and diversification into, the renewable heat sector with further targeted inward investment.'

The plan outlines a range of ideas consistent with the targets to achieve 50% of electricity and 11% of heat from renewable sources by 2020.

Meanwhile Scotland is sticking to its anti-nuclear position. A 126-page report 'Determining and Delivering on Scotland's Energy Future', from the Scottish Parliament's Economy, Energy and Tourism Committee, say: "Scotland does not need a new generation of nuclear power stations to be constructed". Instead, the committee calls for "markedly" increased investments in energy efficiency, renewable energy, cleaner fossil fired thermal plants, and if necessary, the construction of a new generation of larger fossil-plants with future carbon capture.

Nevertheless, in a slight concession, it adds that, since most of its existing coal plants and its two old nuclear stations, Hunterston B, and Torness, are scheduled to close and it will take time for the renewables to catch up, 'there will be a need to extend the operating lifetimes of the current generation of nuclear power stations in Scotland to allow time for the transition to a new electricity system'.

That of course has to be put in context. As SNP MSP Dave Thompson told Newsnight Scotland, 'At the moment we export 20% of the electricity we produce, which is roughly equivalent to the electricity produced by nuclear in Scotland. If nuclear closed down tomorrow, we would still be producing enough electricity to keep us going in Scotland. What we have to look to is the future, where as we develop renewables: we're going to be producing potentially ten times the amount of electricity we actually need in Scotland, so we're going to be exporting massive amounts of electricity to other countries. There's no point in bringing on new nuclear power stations. We just don't need them (and) the Scottish public don't want them.'

The latter assertion may be stretching the point a little. A survey in 2009 of 3,000 people in Scotland, conducted by the Holyrood administration, found that 53% of thought that nuclear energy will be needed in the future to help ensure a secure energy supply, although more people said they preferred renewables to nuclear by a margin of two to one.

As I will be exploring in my next blog entry, subsequently the pro-nuclear position may have strengthened, in Scotland and elsewhere, but the renewables are still supported much more strongly and the Scottish government, like the Welsh Assembly government, has clearly focussed on that.

And there the matter rest for now. None of the proposed 10 new UK nuclear sites are in Scotland or in N.Ireland. One though is in Wales, at Wylfa. Whether that will survive Welsh opposition remains to be seen. It could well be that they will all be in England with, under coalition agreement rules, the strongly anti-nuclear Lib Dems now being unable to vote in opposition, leaving just the Green Party to fight that corner.

The UK offshore wind, wave and tidal power resource could supply about six times current levels of electricity demand, and even if we only exploited part of it, the UK could become a net exporter of power, according to the first comprehensive assessment, The Offshore Valuation produced by an informal collaboration of government and industry organisations co-ordinated by the Public Interest Research Centre (PIRC).

Drawing on published data, it puts the total practical offshore resource at 2131 TWh p/a from 531 Gigawatts (GW) of generating capacity, 406 GW of which would be wind capacity. England had 54% of the total practical resource (286.5 GW), Scotland 39% (206 GW) and Wales 7% (39.5 GW), with wind power dominating in each region.

PIRC point out that their scenarios "are neither predictive nor prescriptive" but calculate that, even if only 29% of the total resource was exploited, by 2050, the UK could have 169 GW of offshore capacity, supplying 610 TWh, equivalent to total electricity consumption by that time, making the UK a net electricity exporter.

Most of the supply capacity (116 GW) would be conventional sea-bed mounted offshore wind but there would also be 33 GW of floating wind turbines, further out to sea, plus 5 GW of wave, 9 GW of tidal stream and 6 GW of tidal-range projects. This would create 145,000 new jobs, provide the Treasury with £28 bn in tax receipts and reduce carbon emissions relative to 1990 levels by 30%.

Under a more ambitious scenario, utilizing 76% of the total practical resource, by 2050 there could be 406 GW of offshore capacity generating 1,610 TWh – about the same as total UK energy demand (not just the electricity demand) expected by then. That would involve an additional 212 GW of floating offshore wind capacity, while wave would rise to 14 GW, tidal stream to 21 GW and tidal range to 10 GW. The jobs total would rise to 324,000, most of these being for the floating wind turbines.

Some of the scenarios are clearly very ambitious. Even using just 13% of the total, to supply 50% of UK power would need a 34 GW mix of back-up/storage/interconnector links to balance variable supplies, and if higher percentages were used then more cross-channel interconnection would also be needed for exporting excess power – 85 GW for the 169 GW scenario and 321 GW for the 406 GW scenario.

So what would it cost? Using DECC figures, PIRC estimates that the 169 GW scenario would cost £443 bn but calculates that in 2050 it would earn £62 bn p.a in net electricity exports. The 406 GW scenario would cost £993 bn and earn £164 bn p.a. Most of the technologies cost £100–125/Mh initially but get cheaper (10% p.a "learning rates" are assumed), though wave and tidal range are more costly, at ~ £175/MWh.

Most of the technology exists or is under development, but floating offshore wind turbines are relatively novel and clearly play a major role in the more ambitious scenarios. As noted in my previous offshore wind blog entry, some floating systems are already under development but there may be limits to what can be obtained from them. The PIRC report states: "The technical limitations of current designs restrict floating wind to water depths of between 60m and 700m. There has also been some concern that it will not be possible to install floating wind beyond 100nm from the coast due to the time taken to get to and from the site." Also "access for installation and maintenance may be limited". Of course, the longer undersea grid links to land will cost more. Even so, the resource is huge. The PIRC puts it at 870 TWh/yr, with a further 660 TWh/yr available beyond 100 nm out. That compares to 180–240 TWh/yr for conventional fixed offshore wind, additional to current site allocations.

The resource for wave and tidal range (barrages/lagoons) is seen as much smaller, at 40 TWh/yr and 36 TWh/yr respectively but that for tidal streams is seen as more significant at 116 TWh/yr. This is larger than some previous estimates. The PIRC says: "Until recently the UK's practical resource had been estimated to lie within the range 4–30 TWh/yr. However, academic research has since highlighted uncertainty in both the underlying methodology and the assumptions used to estimate this resource, which has had the impact of increasing this range to 4–110TWh/yr." It notes that the "kinetic energy flux" method is widely used (e.g. by Black and Veatch) but Stephen Salter's "bottom friction" and David MacKay's "shallow wave" method both give a factor of 10–20 more. To navigate these uncertainties a "bottom-up" calculation was employed by the PIRC to get the technical resource and this was then reduced by 60% to provide an estimate of the practical resource. It was put at 33–200 TWh/yr, corresponding to a power density of 5 MW/k sq m and 30 MW/k sq m respectively. The average of this range – 116 TWh/yr – was used in the report.

The group behind the report, co-ordinated by the PIRC, included the UK, Scottish and Welsh governments, the ETI, the Crown Estate, E.ON, DONG, RWE Innogy, Mainstream Renewables, RES, Scottish and Southern Energy, Statoil, and Vestas. The government's Climate Change Committee also provided some support.

Tim Helweg-Larsen, director of research at the PIRC, said: "To discover that we own a resource with the potential to return the UK to being a net power exporter, and on a sustainable basis, is genuinely exciting, and a wake-up call to those in a position to foster the further development of this industry." But, to put the UK on a path that allows it to access its "substantial and valuable" resource, the PIRC said that Round 3 offshore wind grid connections would have to be made "super-grid compliant" to enable potential future electricity sales to Europe. The PIRC wants the government to take a leading role in the current EU super-grid negotiations, to ensure that the UK derives maximum value from its design and implementation. The domestic supply chain would also have to be developed to enable economic deployment at scale, while new financing structures would have to be created to support the scale and pace of the industrial growth required.

Peter Madigan, head of offshore renewables at trade association RenewableUK, said that "we have long been saying that the North Sea will become the Saudi Arabia of wind energy" and the results of this study "amply bear this out".

As I discussed in my previous blog entry on this topic, environmental impacts must of course be considered. For example, offshore systems have the potential for significant effects on marine wildlife, including dolphins, porpoise, grey seals and wildfowl but a range of environmental studies have been completed or are in hand and so far no major problems seem to have emerged that cannot be limited with by sensible design, location or mitigation measures. So it does seem that the UK could be on to a winner.

Source: PIRC

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