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Under Ofgem's new 'Green Energy Supply' Guidelines, launched in February, suppliers offering 'green electricity' to consumers under the voluntary tariff system must demonstrate that their green tariff involves a commitment above and beyond what is required from existing Government targets for sourcing renewable electricity and reducing emissions. In most cases that will involve some sort of fund to support additional projects, which might include community-scaled renewables or energy saving projects, or even carbon offsetting projects.
The rules for domestic tariffs in the new scheme require that offsetting projects save or avoid the emission of at least 1 tonne of carbon a dioxide equivalent annually, and 50kg of CO2 equivalent emissions p.a. for all other environmental activities, such as community-scaled renewable electricity projects, these all having to be additional to that saved from any existing programmes e.g. as counted within the Renewable Obligation (RO). Basically they can't just use power already credited under the RO. To meet the new rules they must do more, and the new scheme provides specifications, which will be accredited by an independent panel, overseen by the National Energy Foundation. See: www.greenenergyscheme.org
The voluntary green power market has always sat uneasily on the margins of the UK Renewables market- which is driven by the Renewable Obligation. All electricity consumers already pay their suppliers extra for that, so the voluntary green power schemes have to offer something else to give extra value - they just can't charge extra twice for the same electricity used to meet the suppliers RO requirements. Most suppliers have already been offering additional green benefits to justify premium prices- some have set up funds to support green projects. But not all have charged more. For example, npower set up a self -financed fund for its Juice scheme to support new marine renewables projects- it's reached over £2m so far.
Quite a range of schemes have emerged, with there being some confusion and indeed scepticism about the validity of some of the claims to 'green-ness' being made. The new rules puts these schemes, and the additional elements, on a more formal basis.
All the large main suppliers- British Gas, E.On, EDF Energy, RWE Npower, Scottish and Southern Energy and Scottish Power, and linked groups, have signed up to the new scheme, as well as independent supplier Good Energy.
Unlike the 'big six' suppliers, who also sell non-green power, Good Energy buys in and sells 100% green power from mostly local independent sources- and retires any Renewable Obligation Certificates (ROCs) it gets, rather than selling them on. So it claims that it will help renewables to expand, since the value of ROCs will rise proportionately. The other main independent, Ecotricity, sells a roughly 50/50 mix of green/conventional power, which it sees as being reasonable since it is still four times as much green power than currently required by the RO targets. It also charges a premium green tariff rate, but says the income helps it to invest in new renewable energy projects- and it certainly has been pushing ahead with major wind projects.
However Ecotricity has been very critical of the new OFGEM scheme and has not joined. It argues that the renewable energy used under the new tariffs will still all come from Britain's same pool of RO linked renewable electricity, which meant that the big energy companies would not be required to build any extra major source of renewable energy. They will simply provide added-on schemes such as carbon offsetting, help with micro-generation or energy efficiency schemes.
When the guidelines were first proposed last year, Ecotricity's CEO Dale Vince said: 'In these guidelines Ofgem are accrediting everything you can imagine except the thing that really counts- green electricity. Of course we believe in planting trees, protecting wildlife and cutting carbon, all of these things have an important role to play- but not in green tariffs. Green tariffs and consumer choice of green-tariffs- people power- could play a crucial role helping us to reach government renewable energy targets. But Ofgem have sidelined the consumer in one fell swoop by excluding real green electricity from their definition of so-called green-tariffs.'
After the launch earlier this year he reaffirmed his view: 'Green electricity tariffs should be about more than feel-good charity schemes. If suppliers want to plant trees or even help old ladies across the road, I'm all for that but not under the guise of green electricity. Ofgem's new 'rules' set an artificial standard of what green electricity really is. This can only result in them becoming an expensive niche product in a charity ghetto, doing more harm than good. Consumers will get poorer, but Britain won't get any greener as a result of this'.
That may be overstated, after all the new scheme does require real carbon emission reductions, but he may be right in principle- while some small community project may get some support, it won't lead to extra capacity in the mainstream renewables sector. Basically the problem is that the government wants the Renwables Obligation to be the main vehicle for supporting renewables and sees the green consumer tariff as additional and voluntary. Certainly, so far, the uptake has been marginal- only about 2% of UK consumers have signed up to such schemes. What's not clear is what will happen when the new Feed-In Tariffs (FiTs) for small projects come on line from April onwards . Since it's outside the RO, will that power, including some from community projects, be available for 'voluntary' tariff schemes? That might change things, even though the FiT is also only seen as a small, marginal exercise, leading to at most to 2% contribution to UK electricity by 2020.
Elsewhere in the EU, Feed In Tariffs and green energy certificates schemes used by consumers are taken seriously, and have had major impacts. I the UK though they are still seen as marginal- the focus remains on the competitive market orientated RO, despite the fact that, so far, this has been poor at delivering much renewable energy capacity.
For more on renewable energy developments and policies see Renew: www.natta-renew.org
The debate on the UK's new Feed-In Tariff (FiT) has been quite lively, with the Guardian's George Monbiot arguing that, with solar PV being still very expensive, the way the FiT provided the support needed was economically regressive.
It does look that way at first glance – those that could afford to invest say £10,000 in PV might get £1000 p.a. back for the electricity they generated and used, paid for by all the other consumers, who would be charged extra via their electricity bills. It's been suggested that this would lead to a £11 p.a. surcharge on bills by 2020.
However, in a rebuttal to Monbiot's analysis, Jeremy Leggett from Solar Century said "the average household levy in 2013, when tariff rates are all up for review, is likely to be less than £3" and he added "this is far less than the average saving from the government's various domestic energy efficiency measures over the same period. So there is no net subsidy. The levy is not 'regressive' at all".
The extra cost is certainly small, since the expected size of the FiT scheme is small, only maybe leading to 2% of UK electricity by 2020, so maybe this is not a major issue. But it is good to see that the government has now announced a "green-energy loan" scheme (part of its new "Warm Homes, Green Homes" strategy) under which energy-supply companies and others (e.g. the Co-op) may offer consumers zero or low interest loans for installing new energy systems, to be paid back out of the resultant energy savings. Details have yet to be agreed, but up to £7 bn may be made available over the next decade in this way – although it seems it will start off slowly, from 2012 onwards.
This scheme could help the less well-off to invest in new energy technologies like PV, and join in the FiT. Providing up-front loans via a "pay-and-you-save" system certainly seems likely to be more effective at ensuring wide uptake than just using revenue over time from a FiT. And there would be no extra charges on the taxpayer or the other consumers. So it could be popular.
There does seem to be a lot of support for self-generation. A YouGov survey for Friends of the Earth, the Renewable Energy Association and the Cooperative Group found that 71% of homeowners who were asked said that they would consider installing green-energy systems if they were paid enough cash. So perhaps, one way or another, uptake will be significant.
However, there are still some uncertainties. I argued in an earlier blog, before the UK FiT details emerged, that, while it worked very well for wind in Germany, using a FiT to push PV down its learning curve, to lower prices, might not be the most effective approach for PV.
Now we have the details of the tariff, which has set the price for PV so that those who install it get the same rate of return as those using other cheaper options. This may be fine if you are desperate to get PV accelerated. That's a matter of judgment. For electricity, in the UK context, large-scale on-land and off-shore wind is clearly a better bet for the moment in terms of price, and also the scale of the resource. But PV prices are falling, and it could well be next in line for expansion, helped by the FiT, plus the loan scheme. Certainly there are benefits: localized generation using micro-power units like PV do avoid long-distance transmission losses, which can amount to up to 10% across the whole UK, and that is important.
However, domestic micro-generation has it limits – it's arguably the wrong scale. PV is one of the better ones – there are no real technical economies of scale, except via bulk buying and sharing installation costs for larger projects. But micro wind is only relevant in a very few urban UK locations – larger grid-linked machines in windy places are so much more efficient and cost effective. Solar heating (to be supported under the forthcoming Renewable Heat Incentive) maybe be the best domestic option, but even then there are economies of scale (e.g. for grouped-solar schemes sharing a large heat store or even solar-fed district heating). Micro Combined Heat and Power (CHP) similarly: larger-scale mini or macro CHP, linked to district heating networks, are arguably more sensible.
Fortunately the 5 MW UK FiT ceiling, though low, gives us a chance to operate at slightly larger community scale, which may redeem the whole thing. See the excellent Energy Saving Trust report Power in Numbers, which states that "the economics of all distributed energy technologies improve with increasing scale, leading to lower cost energy and lower cost carbon savings and justifying efforts for community energy projects". And for some smaller-scale renewables, it adds that "it is only when action occurs at scales above 50 households, and ideally at or above the 500 household level, that significant carbon savings become available".
The use of tidal energy for generating electricity is moving ahead rapidly around the world, and the potential for expansion is significant, with the emphasis being on tidal current turbines, although some tidal barrages are also being developed or planned – for example, various barrage and lagoon scheme are still under consideration for the Severn estuary. A decision on which to go for should emerge later this year.
The global potential is quite large. Trade network Tidal Today's second annual 'Tidal Summit', held in London last November, heard from a speaker from the Fraunhofer Institute for Wind Energy and Energy System Technology (IWES) who relayed some estimates of tidal energy potentials: China: 50 TWh p.a; Ireland: 10 TWh; UK: 31 TWh; France: 10 TWh; Norway: 3 TWh; US: 115 TWh. The big ones, in terms of capacity, included Canada: >40 GW and South Korea: 1000 GW.
In terms of tidal turbine development and deployment, the UK still leads the pack, with Marine Current Turbines' 1.2 MW Seagen in Strangford Narrows to be followed soon by a 10MW tidal farm off Anglesey – MCT has just got £4.8 m from Siemens, EDF Energy, HighTide and others for the next stage. Meanwhile, the European Marine Energy Centre (EMEC) on Orkney is providing key test facilities for UK devices and systems from overseas. It has the world's only grid linked tidal test facilities – five open sea births, with 11 kv, 5 MW subsea cables. And, as the Crown Estate noted at the Summit, Scotland has 25% of the available European tidal potential – Pentland Firth and Orkney Waters contain six of the top-10 UK tidal sites. Crown Estates seem to have been taking their time assessing these, but are about to announce site licenses for selected projects. So prospects for the future look good.
One of the leaders of the new projects is Open Hydro's novel 'open centre' rim generator turbine, which was tested at EMEC. There are plans for deployment off Alderney and in the bay of Fundy. Next up, Atlantis Resources Corp, the international marine energy company, is to test its AK-1000™ tidal turbine at EMEC this summer. Tidal Today reported that the AK-1000™ has been designed specifically for harsh marine environments. It features what are claimed to be the world's most efficient blades – 18 meters rotor diameter – and has minimal moving parts. It should be capable of generating 1 MW of power in a 2.6 m/s tidal current. The company says that it will award contracts associated with the deployment supporting over 100 UK jobs. The AK-1000™ will be its second grid-linked turbine. Its Nereus turbine in San Remo, Australia, first deployed in 2006, still continues to generate power for the grid.
The US is also active in the field. The summit heard updates on Verdant powers seven turbine projects in New York's East River, and there are several other North American projects, including the Canadian 'Clean Current' ducted rotor, which is now being developed in conjunction with Alstom. At the summit it was reported that 'in September 2006, clean current installed a 3.5 m diameter, 65 kW demonstration unit at race rocks, BC, Canada,' and that 'performance met or exceeded expectations'. On-going testing is now being carried out, with a view to installation in the Bay of Fundy.
There's also a lot happening in South Korea – who seem likely to become the world leader. Developer Voith Hydro noted that tidal range (barrage) projects in planning/execution included Shiwa: 254 MW; Garorim Bay 520 MW; Incheon Bay: 1320 MW, and that the Korean Ministry of Knowledge Economy estimates tidal current potential at 470 MW. Voith are installing 100 MW of its 500–1000 kW propeller type turbine at Jindo, Jeollanamdo Province and there's also a project involving the UK's Lunar Energy ducted-rotor system.
But not everyone was quite so positive. RWE npower told the summit that costs and financing were still issues. There was an 'immature market so commercial costs are not yet apparent' and 'utilities won't loss lead demo projects for uncertain future market – demo projects must promise stand alone economic returns'. There were also 'inadequate support mechanisms'. And there was a 'massive offshore wind potential', whereas tidal 'has a fair way to go'. Consultants Douglas Westwood evidently felt similarly: they told the summit that it cost about '£60 m to take a device through to commercialization' and felt that the 'forecast of 41 MW installed capacity by 2013 may be missed', and that without proper support, tidal might only provide '1% of UK power generation capacity by 2030'.
Fortunately, in February the UK government finally got its support system working and has allocated £22 m from its new Marine Renewable Proving Fund (MRPF), to six projects, two wave systems (Osprey and Pelamis) and four tidal current projects – using new turbines from Atlantis, Voith, MCT and Hammerfest Strom UK.
The MRPF is managed by the Carbon Trust, which notes that all of the devices receiving MRPF funding will be deployed in UK waters, and will stimulate supply chain opportunities associated with construction and deployment of these technologies, with over 75% of the funding released through the MRPF going to the UK supply chain.
The MRPF aims to accelerate the development of marine energy devices to the stage when they can qualify for the Government's existing, but so far unused, £42 m Marine Renewables Deployment Fund (MRDF) support scheme and, ultimately, be deployed on a commercial scale, with support from the Renewables Obligation. MCT's Seagen has in fact managed to jumped straight to that, after several years of grant aided and independent development, and is now getting 2 ROCs/MWh for its 1.2 MW unit in Strangford Narrows. The new MRPF money means that it, and the other developers, can now get moving on new projects.
In addition to those already mentioned, there is quite a range of projects at the starting gate, or at least under development, with some novel UK designs emerging. Scottish projects are well represented, with for example the Scotrnewables' floating device and TidalStream Ltd.'s unique tidal turbine platform design – Triton. But Wales is also in the race, with Swanturbines' Cygnet, developed at Swansea University, and Tidal Energy DeltaStream device, which is to be put through trials at Ramsey Sound, near St Davids.
Humberside is also figuring strongly. For example, following tests on models at the University of Hull, a full-scale prototype of Neptune's ducted vertical-axis turbine 'Proteus' device is being tested in the Humber Estuary at Hull. Pulse Tidal's hydrofoil device is also under test in the Humber. Its 100 kW test rig currently feeds power to a chemicals company on the banks of the river. Tidal Today reported that it is to receive a grant of €8 m from the EU's technology research and development fund (Framework Programme 7) to enable the company to begin work immediately on developing its first fully commercial tidal energy generator – a 1 MW unit, to be commissioned in 2012.
Not all of the many new tidal current devices emerging will succeed or get sufficient funding to prove themselves. But there is a mood of pioneering enthusiasm, with developers like Pulse Tidal's chief executive Bob Smith, being very positive about the future: 'We have developed an economic way to recover predictable, renewable energy from the tides and are entering a young market predicted to be worth at least £6 bn annually in electricity sales'. He added: 'The Pulse system is expected to match the cost of offshore wind after only 100 MW has been installed. In the future tidal energy is set to surpass wind as the most economic and predictable source of offshore power.'
* For more information, visit www.tidaltoday.com.
What happens in China, in terms energy use, is widely seen as a key to whether serious global climate impacts can be avoided or limited. China is relying heavily on coal but is also turning increasingly to non-fossil energy sources. Its nuclear programme often gets the headlines but in 2008 China had as much wind capacity in place as it had nuclear capacity – 8.9 GW. Of course, the relatively low load factor for wind (under 20%) meant that nuclear produced more energy – 68 TWh as against 13 TWh for wind. Moreover, new nuclear plants are planned, including fast neutron reactors to be supplied by Russia. In all, plans announced in recent years call for nuclear stations to supply 4% of China's power needs by 2020, up from about 2% now, although of course its energy use is expanding rapidly, so that is more than a doubling in capacity. But wind has now more than doubled – installed capacity reached 25 GW in 2009, and a 2020 wind target of 150 GW has been mentioned. China's wind programme is also moving offshore: it recently installed its first 3 MW 90-metre diameter "Sinovel" offshore turbine, the first unit of a 100 MW Shanghai Donghai Bridge demonstration project.
Certainly renewable energy, along with clean coal (i.e. with carbon capture) seems to be seen as a key way ahead. Chen Mingde, vice-chair of the National Development and Reform Commission, in comments quoted by the China Daily newspaper last year, claimed that "nuclear power cannot save us because the world's supply of uranium and other radioactive minerals needed to generate nuclear power are very limited". He saw the expansion of China's nuclear power capacity a "transitional replacement" of the country's heavy reliance on coal and oil, with the future for China being in more efficient use of fossil fuels and expanded use of renewable energy sources like wind, solar, and hydro.
China's current target is to get 15% of its energy (not just electricity) from renewables by 2020, although this is likely to be raised to 20%. In addition to wind, it's pushing ahead with solar as well as hydro and biomass. China's hydro capacity is expected to nearly double to 300 GW by 2020. And a recent REEEP study suggested that 30% of China's rural energy demand could be met through bioenergy. China already has 65 GW of installed solar thermal power, and the potential for expansion is significant (e.g. for large scale, concentrating solar power units in desert areas, feeding power by HVDC links to the cities). A 1GW prototype plant is planned.
PV solar is also set to expand rapidly. China is already the largest producer of solar cells globally and, although until recently most of them were exported (around 1 GW in 2007), the emphasis has now changed, so that the current national target of having 3 GW of capacity in place by 2020 could be exceeded by perhaps a factor of three. Looking further ahead, work in also underway on tidal and wave energy projects.
Some major integrated projects are also emerging. For example, Reuters reports that China is currently developing a demonstration zone in Hangjin Banner, with a planned 11,950 MW renewable-energy park, which, when completed, should have 6,950 MW of wind generation, 3,900 MW of photovoltaics, 720 MW of concentrating solar power, 310 MW of biomass plants and 70 MW of hydro/storage.
Some innovative new grid links are also being established, designed to deal with the problem that much of the renewable electricity resource is remote from mostly coastal centres of population. The new extended grid system could also help with balancing the variable output from some renewables. Modern Power Systems reports that Siemens Energy and China Southern Power Grid has started commissioning part of a High Voltage Direct Current (HVDC) transmission line, with a capacity of 5000 MW, covering a distance of more than 1400 km. It's claimed to be the first HVDC link in the world operating at a transmission voltage of 800 kV. Commissioning of the second phase, and startup of the full system, is scheduled soon.
The Yunnan–Guangdong interconnector will transmit power generated by several hydro power plants in central China to the rapidly growing industrial region in the Pearl River delta in Guangdong Province with its megacities Guangzhou and Shenzhen. This system can, it us claimed, reduce the annual CO2 emissions that would otherwise have been produced by fossil-fuelled power plant by over 30 megatonnes. In addition Modern Power Systems reports that there is the 800 kV Xiangjiaba–Shanghai link, on which ABB has been working with the State Grid Corporation of China (SGCC). It will be capable of transmitting 6400 MW of power from the Xiangjiaba hydropower plant, located in the southwest of China, to Shanghai – a distance of over 2000 km. It is claimed that transmission losses on the line will be less than 7%.
China is now the world's largest carbon dioxide emitter and its energy demand is still rising rapidly, despite the global economic recession. However, in the run up to the COP 15 climate negotiations in Copenhagen last December, while not willing to commit to reductions in net emissions, China said it would cut its energy intensity (emissions/GNP) dramatically – by 40–45% by 2020. That's not the same as reducing net emissions of course, but it would be a start. And if that is acted on, renewables would clearly play a major part.
China's role at COP 15 has been much debated – essentially it seemed to want to protect its continued growth, and avoid imposed emission targets targets – much like the US. But, like the US, it also seems keen to be a leader in the move to green energy technology – perhaps becoming the "green workshop of the world" feeding the expanding markets for renewable energy systems around the world. In addition to exporting solar PV cells, it was even planning to build wind turbines for and in the US – although a US senator's objections may have scotched that.
How rapidly China can and will green itself though is less clear. Certainly China has massive renewable resources: for example the wind resource is put at around 2 TW. And a new study by Michael McElroy and colleagues at Harvard and Tsinghua University in Beijing, published in the journal Science, has claimed that, in theory, wind power could meet all of China's electricity demand by 2030.
That is very unlikely happen by then of course, but China is likely to become a major player in the green-energy revolution.
Wind power seems likely to remain the main new renewable energy source for the UK given the large offshore and on land resource and its relatively good economics. However, some lobby groups, like the Renewable Energy Foundation (REF), argue that we have placed too much emphasis on wind and should also look more seriously to other renewable options. Actually, although the British Wind Energy Association (BWEA) sees wind supplying 30% of UK electricity in the decades ahead, it may agree. The BWEA no longer focuses just on wind – it has increasingly been looking to wave and tidal power, particularly tidal current turbines. It has just changed its name, to "RenewableUK" (RUK), to reflect this.
It's not surprising that the BWEA/RUK has been keen to take wave and tidal power under its wing, as well as wind. They can all work together beneficially to help cope with the variability of each source. Wave energy is in effect stored/delayed wind energy and so is less sensitive to wind variations, while tides, though cyclic, are unrelated to wind.
A recent Redpoint scenario, produced for the BWEA, is the starting point for a study of the optimum balance between wind, wave and tidal. In particular it looks at the extent to which wave and tidal power could help reduce the grid balancing costs associated with the use of variable renewables, and also reduce the excess wind "spillage", when there was too much wind to be used on the grid. The study, The Benefits of marine technologies with a diversified renewable mix, suggests that, to get the best from the different time correlations of these sources, the optimum might be around a 70% wind and 30% wave/tidal current mix, or, if tidal range projects were included, along with tidal current systems, a 60/40 wind to wave/tidal ratio. The former ratio could reduce the need for fossil fuel backup plants by 2.15 GW, the later by 2.3 GW, and the overall carbon savings could be increased by up to 6%, with wholesale costs reduced by up to 3.3%, since there would be less spillage of wind.
All of these options are about electricity production, and are mainly on the larger scale, whereas it can be argued that smaller scale electricity generation, and also renewable heat production, are equally important in developing an optimal mix. The BWEA has taken an interest in micro wind, but otherwise it has mainly been another trade lobby, the Renewable Energy Association (REA), which has covered the microgeneration area (e.g. PV solar), along with biomass-based heat and power generation (e.g. micro CHP). One of the REA's main strengths has always been biomass/waste related energy systems, including sewage gas, landfill gas and other sources of biogas, with new community-scaled AD (Anaerobic Digestion) plants being one of the latest growth areas. Along with others, it's pushed hard for a Feed-In Tariff for micro power systems, with some success – the government is introducing a clean Energy Cashback scheme for small project in April.
A year or so ago the BWEA and REA were discussing a merger, but that came to nothing. So now, while BWEA/RUK will focus on wind, wave and tidal, the REA will be left covering the rest – and possibly, increasingly, renewable heat options. That's the focus of the proposed new Renewable Heat Initiative Feed-In Tariff that the government is planning, to start next year. It's also something that the REF has focussed on in their belief that we need a more diversified approach.
The division of areas of technological interest by the trade lobbies is not absolute (e.g. REA still has a strong interest in wave and tidal power). And while some sort of rough division may make sense institutionally, it would be a shame if the potential for a more integrated approach was reduced – there is a lot of overlap. BWEA/RUK and REA have collaborated in the past. Hopefully that will continue. After all, what seems likely to emerge is a new energy system in which a range of electricity and heat producing renewable energy based technologies, large and small, are integrated together to balance heat and power needs via heating networks and smart power grids. For example, along the lines proposed by Neil Crumpton – as I reported in an earlier post.
The issue of integration, and of choosing the right mix of renewables, will no doubt be high on the agenda being addressed by Prof. Bernard Bulkin, ex-BP and ex-AEAT, who is now the "expert chair" of DECC's new Office for Renewable Energy Deployment. DECC is currently looking at what we might expect by 2050. It will be interesting to see what emerges in its "2050 Roadmap", which should be published in conjunction with the Budget in April.
www.renewable-UK.com
www.bwea.com
www.r-e-a.net
www.ref.org.uk
Most people are surprised how quiet modern wind turbines are when they visit a wind farm. Mechanical noise is usually minimal – even right up close. And the aerodynamic blade noise is often less than the noise of wind in any trees or bushes near by. However in some locations some problems have still been reported.
An international panel of experts convened by the American and Canadian Wind Energy Associations, recently released a report based on a review of a large body of scientific literature on sound and health effects with regard to sound produced by wind turbines. After extensive review, analysis and discussion, the panel concluded that sounds or vibrations emitted from wind turbines have no adverse effect on human health – an issue that was recently given new prominence by a US report, which claimed that physiological damage could be caused by low-frequency sound from wind turbines (see my earlier blog).
The new review states:
- There is no evidence that the audible or sub-audible sounds emitted by wind turbines have any direct adverse physiological effects.
- The ground-borne vibrations from wind turbines are too weak to be detected by, or to affect, humans.
- The sounds emitted by wind turbines are not unique. There is no reason to believe, based on the levels and frequencies of the sounds and the panel's experience with sound exposures in occupational settings, that the sounds from wind turbines could plausibly have direct adverse health consequences.
Even so, there are still reports that aerodynamic "swishing" sounds from wind farms are an issue at some sites at night – disturbing some people's sleep. The Telegraph quoted a nurse, Jane Davis, who says that she was forced to move from her home in Lincolnshire after eight wind turbines were built in 2006. "All I know is the amount of health problems people have suffered," which she said included sleep deprivation, tinnitus, depression and psychological stress "seem to be excessive". She added: "These things have devastated my life."
The AWEA/CWEA report does say that, although "work with low frequencies has shown that an audible low frequency sound does not normally become objectionable until it is 10 to 15 dB above hearing threshold", an exception is "when a listener has developed hostility to the noise source, so that annoyance commences at a lower level". They note that "a major cause of concern about wind turbine sound is its fluctuating nature; some may find this sound annoying, a reaction that depends primarily on personal characteristics as opposed to the intensity of the sound level" and report that a "study of more than 2000 people suggested that personality traits play a role in the perception of annoyance to environmental issues, such as sound".
However, they add, a bit abruptly perhaps, that though "some people may be annoyed at the presence of sound from wind turbines; annoyance is not a pathological entity". It's certainly true that once a noise gets annoying, however low the level (e.g. a tap dripping), it can become intolerable.
The report concludes that, though "there is no evidence that sound at the levels from wind turbines as heard in residences will cause direct physiological effects…a small number of sensitive people, however, may be stressed by the sound and suffer sleep disturbances".
That rendition may not please sufferers! Of course, you could say that road traffic and aircraft landing and taking off can lead to much more noise annoyance for a lot more people, as can city living. But should we be adding more stress? Rural areas are, after all, usually quieter, which is one of their attractions. Or, assuming it cannot be resolved by careful wind-turbine location or modified operational patterns, is that just a cost that has to be borne by a small minority, who might in any case find a conventional power plant near them significantly less attractive?
The government's view certainly seems unchanged. NewEnergyFocus reported that in January, energy minister David Kidney dismissed claims that the permitted night-time noise limit for onshore wind turbines is too high. He said that the 43 dB night-time limit in the ETSU-R-97 guidance was derived from the sleep disturbance criteria in Planning Policy Guidance 24, with an addition to allow for an open window. He said that ETSU-R-97 gave indicative noise levels thought to offer "a reasonable degree of protection to wind farm neighbours" and that there was no evidence that they needed to be reviewed. He added that residents' comfort had to be balanced with the needs of wind-farm developers and so the guidelines should not place unreasonable restrictions on wind-farm development or add unduly costs and administrative burdens on wind-farm developers or local authorities. He concluded: "We have no robust new evidence to suggest that the current guidance is not achieving its aim."
In April the government is to launch a Feed In Tariff for small renewables- the 'Clean Energy Cashback' scheme – and details of the tariff rates should emerge next week. Under it, electricity supply companies will offer guaranteed payments for electricity generated from renewable energy devices that consumers have installed their own homes, or to small projects installed by community organisation and the like, the limit being 5MW. See my earlier blog for details: http://environmentalresearchweb.org/blog/2009/10/uk-tries-to-get-fit.html
Eligible technologies include micro wind turbines, photovoltaic modules, micro hydro plants, and biomass-fired units. In the domestic sector, PV solar seems likely to dominate – micro wind is only really viable in a limited number of places and micro biomass units for electricity generation (usually micro CHP) are still relatively novel.
The Feed-In Tariff (FiT) that has been running for several years now in Germany has certainly helped get PV established, so maybe that will also happen here. The theory is that this guaranteed subsidy helps build the market for PV, so that prices begin to fall – and the FiT support can then be reduced. The German system has a built-in annual price 'degression' formula to take account of that. And it seems to work – PV prices have fallen and installed capacity has grown.
However, it has to be said that this has come at a cost: the supply companies pass on the FiT charges on to all electricity consumers. PV is expensive. But since the PV element the German FiT has so far been relatively small (most of the FiT has been used to support wind, which is cheaper) the overall cost of the FiT to consumers has been relatively small – initially 3–4% or so extra on average bills. However, with demand for PV increasing due to the FiT and the reduced cost of PV, there have been concerns about loading consumers up with the higher costs. That has already led to a cap on total PV capacity supported under the FiT in place in Spain. And the German government has now decided to reduce the FiT support rate for PV by15% to reduce the cost to consumers.
Initially, the German government was clearly convinced that PV was a major option for the future – as is widely accepted to be the case. It did of course have to balance the costs to consumers, the expected reduction in prices as the FIT helped PV move down its learning curve, and how much capacity was wanted, but it obviously felt that it was right to push PV ahead rapidly. Now, however, following a shift to the political right, it's being more cautious. That change was no doubt buttressed by claims by the German news magazine Spiegel that the additional costs for subsidizing new PV installations in 2009, based on initial industry estimates for new installations of around 700 MW, could be as high as €10bn over the course of the 20-year FiT programme. And also by the study published last year by RWI (Rheinisch-Westfaelisches Institut für Wirtschaftsforschung), which claimed the extra cost added to consumers bills was around 7.5% p.a., and calculated the total cost of PV to German electricity users could be more than €77 bn over a 25-year period. These estimates may be inflated: the German Institute for Economic Research (DIW) put the latter cost at €50 bn. But it did seem that a continuing rapid expansion of PV was going to put more cost on consumers.
Basically the problem is that, although they are falling under the FiT, PV costs are still high at present, much higher than for other renewables, and the rapid expansion of PV meant the cost to consumers was too high. A problem really of success! By contrast, near-market options like large wind turbines are much cheaper/kW and per kWh, and so FiT support for wind cost consumers less in total. And so wind has been the main focus, with the result being that the German FiT has helped support 25 GW of wind capacity, and only about 4 GW of PV.
What does this mean for the UK? If FiT's aren't that good at supporting expensive options like PV without loading up consumers with high costs, arguably we've got it the wrong way around in our approach. FiTs should be used for the big cost-effective stuff. We are using it for the small expensive stuff.
It could be that, nevertheless, as the UK's 'Clean Energy Cashback' FiT gets going, customers who are willing and able to borrow money to install the equipment will push ahead, as happened in Germany. The guaranteed FiT income does make it easier to get loans from banks. And it's certainly better than the than the UK's dismal ROC/Renewables Obligation system. But what smaller expensive projects like PV really need is up-front capital grants. The UK tried that earlier with the PV grants system in the Low Carbon Building programme – but the level of demand for grants was such that it overwhelmed the relatively small scheme, and there were limits to how much more taxpayers money the government felt it could provide. Hence the interest in a FIT for PV and other small renewables – then its the consumers who pay.
The FIT may work well for some people. At present, for those with money, investing in PV solar will give a better return, via the FiT, than banks offer! But what about those without money? In the pre-budget report last December, the government said that 'although feed-in tariffs and the Renewable Heat Incentive will make payments over the life of installations, low-income households may still find it difficult to meet upfront costs'. It added that 'building on the experience of pilot projects for Pay as You Save financing and Warm Front,' it will consult 'on measures to help low-income households take advantage of clean energy cash-back'. That could help. And some community schemes may also prosper.
Even so, sadly, not much is expected on the UK FiT. At best, the government sees it as delivering just 2% of electricity by 2020. The Renewables Obligation (RO) is seen as the main way ahead, helping us to get about 30% from renewables, mostly wind, by 2020. So far, using the RO, plus a few capital grants, we've barely made it to 6%, with only tiny amounts of PV. And the RO has loaded up consumers with much higher prices per kW and kWh than under the German FiT system- even though the latter also included support for much more PV. Ofgem, the energy regulator, has reportedly estimated that the RO cost consumers £1 bn last year and a total of £4.4 bn so far. But it has only helped support 4 GW of wind generation capacity (some of which also benefited from grants), compared to the 25 GW installed under the FIT in Germany. So in general, in terms of capacity and costs, FITs are a much better option.
Whether that will prove true of the limited UK version for small projects remains to be seen. It will be interesting to see what the government comes up with next week in terms of tariff levels. Will PV get enough to move ahead seriously? And if so, what will that cost us?
Interest in using the scheme seems high. A YouGov survey for Friends of the Earth the Renewable Energy Association and the Cooperative Group found that 71% of homeowners said they would consider installing green energy systems if they were paid enough cash – and 64% of those asked thought that the government's plans were not ambitious enough. But what if it puts bills significantly? The poll showed that 70% of respondents said that they would be prepared to pay an extra 10p on their electricity bills each month (£1.20 annually), on top of the already proposed annual increase of £1.17, until 2013 when the scheme is due to be reviewed. So maybe there is an appetite for change.
Neil Crumpton, a member of the Bath-based Claverton Energy Group of energy experts and practitioners, and also Friends of the Earth Cymru's energy campaigner, has produced a draft zero-carbon, non-nuclear scenario to 2050 and beyond intended to initiate feedback and debate in the Claverton Energy Group. It aims to identify the low-carbon energy generating and supply infrastructure needed to build a resilient, demand-responsive UK energy system. It relies heavily on renewables, urban heat grids, possibly suburban hydrogen networks, and carbon capture and storage (CCS) during the four decades of transition.
It is very ambitious. Renewables would supply about 200TWh/y by 2020, scaling up to more than 1,100 TWh/y by 2050. Offshore windfarms, at least 10 miles from any coast occupying some 20,000 sq. km, would supply ~ 550 TWh/y, about half his estimated 2050 final energy demand. But the real innovation starts on the heat side, with much use of Combined Heat and Power plants and large heat pumps feeding industrial users and town/ city heat grids. Up to 15 GWe of industrial Combined Heat and Power (CHP) plants would supply industrial clusters, while 15 GWe or more of urban Combined Heat Pump and Power (CHP&P) schemes (typically 0.5–100 MW) would distribute reject heat from fast-response 'aero-derivative' gas turbines, and large heat pumps.
They would feed heat grids, with up to 5 GWe of 'initiator' CHP&P schemes, progressively linked up to form wider district and eventually town-wide and city-wide heat grids over the next 15–20 years. Large-scale heat pump installations would deliver renewable heat from air and ground- and from solar thermal and geothermal sources.
Even more innovatively, large thermal stores (accumulators), up to traditional gasometer-scale, would optimise the system. Peaking renewable electricity, particularly from marine technologies, would primarily be stored as heat at electricity 'regenerator' sites comprising a mix of technologies like molten salt stores and 10 GWe or more of steam turbines, electrolysers and hydrogen fuel cells and compressed air. Chemicals and fuel synthesis could also feature and connection to the heat grids would greatly aid conversion and regeneration efficiency and heat demand response.
Crumpton says 'such an energy storage and electricity regeneration capability would be a significant aid to delivering the UK's large but highly variable renewable energy resources, particularly wind energy, to consumers as and when demanded'.
Initially the energy input for the heat grids would be mostly from gas, but all the gas-fired industrial CHP and urban CHP&P capacity would be progressively converted to hydrogen, piped in from coal and biomass CCS gasifiers. There could also be a direct solar heat input to local heat stores, and possibly also some from geothermal sources. Low-pressure hydrogen might also be supplied to the 9.5 million sub-urban homes via the existing (upgraded) gas network to power 10–30 GWe of mCHP boilers (possibly fuel cell) and domestic heat pumps.
All large emitters would be fitted with Carbon Capture by 2025. CCS fitted gasifiers co-fired with 15+% biomass or imported solar synthetic fuels would then provide 'carbon-negative' baseload to the extent climate protection policy required. The 10 GW of CCGTs already consented would operate until about 2040, then be retained for occasional duty during prolonged winter anti-cyclones.
There would also be HVDC links to Europe, including Norwegian hydro and pumped storage schemes, which would help optimise the system to high marine renewable variability, and open the option of delivering net imports of around 10% of final energy from Saharan wind and concentrated solar power schemes.
The complete system, with molten salt heat stores at regeneration sites, would comprise some 50 GW of firm electricity generation, plus peaking plant, suburban mCHP, and inter-connectors. He says the system's firm generation and storage capacity would be designed to supply 'smart' demand even during a deep winter anti-cyclone lasting days. And he says that 'Depending on the availability of sustainable bio-sources and transport sector emissions, the UK could be net zero carbon by 2040'.
It is of course all very speculative, although the use of large heat pumps is not novel- The Hague has a 2.7 MW (ammonia) seawater community heating scheme and Stockholm has a total of 420 MW (multiple 30 MW units) of heat / cold pumps feeding its district heating / cooling grid. Crumpton says 'The large heat pumps would harness heat from sources which 11 million urban domestic heat pumps could not do, including large solar thermal arrays and geothermal'.
Using coal still might worry some environmentalists, but there would be CCS and he says it would be used in minimal amounts by 2050. Generating and piping hydrogen is also a novel idea – but there are now some pilot schemes in the UK. And piping heat is much more common – on the continent.
Installing that, and the rest of the system, would though involve a lot of new infrastructure, but he claims that 'strategic siting the gasifiers would combine locations with good transport access for coal and biomass (dock-sides, railheads, collieries), together with hydrogen pipeline routes to CHP schemes, and CO2 pipelines to geological storage sites under the North Sea or Liverpool Bay'. And similarly 'regeneration schemes should be sited adjacent to industrial clusters, refineries, and existing chemical sites with hydrogen, CO2 and heat grid pipeline access'. In addition, 'coastal locations with direct HVDC connection from marine renewables would minimise need for new cross-country transmission lines'.
So disruption would be reduced. Nevertheless, building the heat grids (polypropylene pipes) would involve some short-term local disruption to pavements and roads during the pipe/conduit laying. But he says it would 'provide low-carbon energy infrastructure for the children of today and future generations'.
The draft scenario is outlined in more detail in the current issue of Renew (183): www.natta-renew.org
The debate over how to deal with the variable energy output from wind turbines continues to rumble on. Some say that, when wind availability is low, there will be a need for extensive back up from conventional plant to maintain grid reliability. However, this backup may already exist: we have a lot of gas-fired capacity, much of which is used regularly, on a daily basis, to balance variations in conventional supply and in demand. Balancing wind variations means this will just have to be used a few times more often each year, adding a small cost penalty and undermining the carbon savings from using wind very slightly. But some say we will need much more that that. A report from Parsons Brinckerhoff (PB) claims that "the current mix of generating plant will be unable to ensure reliable electricity supply with significantly more than 10 GW of wind capacity. For larger wind capacity to be managed successfully, up to 10 GW of fast response generating plant or controllable load will be needed to balance the electricity system".
www.pbpoweringthefuture.com
"Controllable load" includes the idea of having interactive smart grids which can switch off some devices when demand is high or renewable supplies are low.
However even if that option is available, some say that, with more wind on the grid, to meet peak demand, we will still need more backup plants than we have. By contrast, wind energy consultant David Milborrow claims we have enough, and that some fossil-fired plants can actually be retired when wind capacity is added. That depends on the "capacity credit" of wind – how much of the wind plant capacity can be relied on statistically to meet peak demand. Milborrow puts the capacity credit of wind at around 30% with low levels wind on the grid, falling to 15% at high levels (at say 40% wind on the grid). That indicates how much fossil plant can be replaced.
www.greenpeace.org.uk/media/reports/wind-power-managing-variability
PB see it very differently: "A high penetration of intermittent renewable generation drastically reduces the baseload regime, undermining the economic case for more-efficient plant types with lower carbon emissions."
Milborow admits that balancing wind variations has the effect of reducing the load factor for thermal plant, but says that this only costs ~£2.5/MWh at 20% wind, or ~ £6/MWh at 40%. PB will have none of this: "Very high early penetration of wind generation is likely to have adverse effects on the rest of the generating fleet, undermining the benefits of an increased contribution of renewable electricity."
PB also seems to slam the door on a possible way out, importing power from continental Europe, the wider footprint then helping to balance variations across a much larger geographical area. It says: "Electricity interconnection with mainland Europe would offer some fast-response capability, but would be unlikely to offer predictable support. Without additional fast-response balancing facilities, significant numbers of UK electricity consumers could regularly experience interruptions or a drop in voltage."
Addressing the interconnector issue, among others, TradeWind, a European project funded under the EU's Intelligent Energy-Europe Programme, looked at the maximal and reliable integration of wind power in Trans European power markets. It used European wind power time series to calculate the effect of geographical aggregation on wind's contribution to generation. And it looked ahead to a very large future programme, with its 2020 Medium scenario involving 200 GW – a 12% pan-EU wind power penetration. It found that aggregating wind energy production from multiple countries strongly increased the capacity credit.
www.trade-wind.eu
It also noted that "load" and wind energy are positively correlated – improving the capacity factor – the degree to which energy output matches energy demand. For the 2020 Medium scenario the countries studied showed an average annual wind capacity factor of 23–25 %, rising to 30–40 %, when considering power production during the 100 highest peak load situations – in almost all the cases studied, it was found that wind generation produces more than average during peak load hours.
Given that "the effect of windpower aggregation is the strongest when wind power is shared between all European countries", cross-EU grid links were seen as vital. If no wind energy is exchanged between European countries, the capacity credit in Europe is 8%, which corresponds to only 16 GW for the assumed 200 GW installed capacity. But since "the wider the countries are geographically distributed, the higher the resulting capacity credit" if Europe is calculated as one wind energy production system and wind energy is distributed across many countries according to individual load profiles, the capacity credit almost doubles to a level of 14%, which it says corresponds to approximately 27 GW of firm power in the system.
Clearly then, with very large wind programmes you do get diminishing returns and need more backup, but it seems that can be offset to some extent by wider interconnectivity – the supergrid idea, linking up renewables sources across the EU.
That is already underway. The UK's National Grid has agreed with its Norwegian counterpart Statnett to draw up proposals for a £1 bn grid-interconnector grid link-up, to be funded on a 50:50 basis, which could help solve the problem of winds intermittency, given that Norwegian hydro could act as back-up for the UK, in return for electricity from the UK on windy days. As yet no UK landfall site has been indicated, but it could include connection nodes along the route with spurs taking power from offshore wind farms and become the backbone of a new North Sea "supergrid": the UK and eight other North West EU countries have now agreed to explore interconnector links across the North sea and Irish sea. National Grid said: "Greater interconnection with Europe will be an important tool to help us balance the system with large quantities of variable wind generation in the UK."
In recent years, "science" has increasingly been asked to provide guidance on issues such as climate change. However, there are limits both to what science can do and to its influence. For example, although there has been much talk of relying on "evidence-based research" as a guide to action, in reality, decisions are often made on the basis of other information, or views, or influences. In some cases science is just used to justify decisions already taken. Scientists are very much "on tap, not on top".
Science is not, however, entirely impotent. Climate change has been an example of where science has created a new agenda. But that involves some responsibilities. Given the cultural and ideological relativism that seems to be the norm these days, it is perhaps not surprising that some have latched on to the climate change issue as a new fundamentalism. Here at last was a really powerful determinism, providing a clear "scientifically backed" case, with added moral an ethical imperatives for the sort of technical, social and political prescriptions preferred by, among others, radical "greens". It has, for some, gone beyond science and on to a belief. Hence the bitterness at any hint of climate-change denial, or any scepticism about humans being responsible for it.
Trying to sustain this degree of absolute certainly, and denying rival views, is bad for science, which needs open, pluralistic, debate and challenges to keep it as objective as possible. That is not to say that all views have equal weight. There are processes for weighing the strength of arguments and analysis, for testing conjectures, checking data. The "scientific method" may not be perfect – it's a human system after all – but it is arguably the best that we have come up so far for trying to make sense of the material world.
As far as climate issues are concerned, what it has suggested is that, with about 90% certainty, climate change is underway and is mostly due to human actions. That still leaves room for other views – and other explanations. Less palatably, it also leaves room for bitter disagreements and invective. Some climate sceptics attribute base and deceitful motives to some climate scientists – and vice versa. "They" are, variously, in the pay of evil oil companies/or devious eco-fascists/leftists, and so on.
The recent (Nov 2009) affair involving e-mail leak at the UEA played well to the sceptics – and even to the full-on climate-change deniers. It even worried fundamentalist climate-change believers – some of the scientific priesthood looked like it might be corrupt! The reality seems to be that some poorly worded descriptions of quite normal data-processing activities were made public: with many data sets, it is necessary to subtract spurious trends to see what is actually the main process at work. That can of course sometimes be controversial: but we rely on scientists to make it clear what they are doing and why, to their peers, so that their analysis can be tested and, if necessary, challenged. This is not best done by leaked e-mail extracts and invective from climate sceptics. After all they are often, to put it mildly, prone to deceitful use of data. Pots calling Kettles black, springs to mind. Even so, this episode does remind us of the need for proper scientific rigor – on all sides.
Other leaks concerned the peer-review and publishing process, which is how analyses and conclusions are meant to be tested and checked. A degree of collusion seems to be implied – in part, evidently, to keep deviant views out. This is much less palatable. The risk is that we end up with a self-serving, self-selected elite, who review each others papers and funding bids. I am sure most climate scientists are not like this; what motivates them is finding the truth. But in the face of ever increasing, often very illiberal and incoherent attacks by climate deniers and sceptics, it is understandable that some scientists may resort to defensive measures – by "keeping nutters out". That is tragic if it corrupts the debate, which should be as open as possible. But both sides have to play by reasonable standards, to have a proper debate. Some climate deniers and sceptics do not. So it is understandable that some climate scientists feel that they have to fight back, and for example publicly disparage views they see as dubious. But, although there is a need for more "public understanding of science", it is demeaning for scientists to get too involved in brawls with lobby groups, some of whose mission seems to be an ideological one. It might be better to leave that to green pressure groups and the wider political process, and focus instead on cleaning up your own act, so that there are no reasons for adverse publicity.
All that said, in an imperfect world, maybe we have to accept the need for virulent sceptical oversight of all things, including science. So the climate sceptics may have done us all a favour by putting the scientists' work under tighter scrutiny. But if cynicism sets in across the board, then we are not much further forward, and we may even be losing ground to those who say all that matters is ''belief". Faith may be a wonderful thing, and vision too – science is not the whole story. As the UEA's Mike Hume noted in a recent Guardian article, science can't help you decide about values or ideology. But science, properly done, can help when you are trying to decide politically about practical changes in material reality.
Hume: http://www.guardian.co.uk/commentisfree/2009/dec/04/laboratories-limits-leaked-emails-climate.