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February 2012 Archives

ERL presents the Rosenfeld plaque to Dr Carey King

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Environmental Research Letters (ERL) is pleased to present this one time award in recognition of outstanding work in the journal in the field of energy economics.

ERL awards the Rosenfeld plaque to Dr Carey King for his work published in the journal, where he described a new method to measure energy return on energy invested (EROI) that can be estimated every year, rather than the previous best method which gave estimates at best every five years. In recognition of Dr King's work and as a gesture of gratitude, the journal would like to give Dr King the opportunity to publish in ERL completely free of charge until the end of 2012.

The Rosenfeld plaque is a limited edition item, named in honour of Dr Arthur H Rosenfeld, which was manufactured to commemorate a letter published in ERL in March 2010 that defined a new unit to represent energy savings.

To highlight Dr King's work further, alongside this award ERL has published a perspective article written by Professor Charles Hall.

The article (full text HTML link) by Dr King and perspective (full text PDF link) by Professor Hall are listed below:

Read Carey King's blog for environmentalresearchweb.

Can Germany do it?

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In a presentation to PRASEG, the Parliamentary Renewables and Sustainable Energy Group, in London in February, Dr. Georg Maue, from the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, outlined Germany's new energy plan. The basic aim is to reduce greenhouse gas emissions by 40% from 1990 levels by 2020, 55% by 2030, 70% by 2040 and 80% by 2050. The aim is to do this by expanding renewables to 35% of electricity by 2020 (18% of primary energy), moving up in stages to 80% of electricity (60% of energy) by 2050. In addition, primary energy consumption will be reduced by 20% by 2020 and then in stages up to 50% by 2050, with electricity use falling by 10% and 25% respectively. The nuclear plants would all be closed by 2022, the first 8 have been shut already, the rest will close in stages, the last 4GW in 2022.

The German government seems optimistic about reaching the targets. Certainly the payoff could be large. In addition to the emission savings, Dr Maue said that 'If Germany can achieve its 40% carbon reduction target by 2020, at least 500,000 additional jobs will be created, annual avoided fossil energy imports will be worth approx. €22 bn (approx. €38bn in 2030) the national GDP will annually increase by around €20 bn / year, a SURPLUS of 34 € per tonne of reduced CO2eq will be realized in 2030 and the national debt would be some €180 bn Euro lower than it would be without climate protection measures'.

However there could be problems. Some say that, to replace the output from the nuclear plants, Germany will have to import more coal and gas and even electricity. So far, that's not been a problem. Germany exported 4 TWh more power than it imported in the first half 2011, despite the nuclear closures, although the exports were down from 11 TWh in 2010. Interestingly, in the recent cold spell, France had to import power from Germany. Longer term, as the proportion of renewables build up in Germany, imports should be even less of an issue, except perhaps for grid balancing, when wind and solar inputs in Germany are low.

That of course is only one approach to grid balancing. There are a range of other strategies available to compensate for the variable wind and solar inputs, including the use of stored power from pumped hydro plants- which can take excess wind generated electricity when available. In addition gas fired plants can be used as backup, ramping up to meet lull and down when there is plenty of wind and/or sun energy. The only problem with that is that it can make the gas plants less economic to run.

This, and that fact that wind power is cheap with low marginal cost they don't need fuel), has already has already had an impact. Norwegian utilty Statkraft is considering shutting two of its 450MW natural combined cycle gas-fired power plants (CCGT) in Germany because the availability of cheaper power from wind farms, which, when generating, get priority access to the grid under the Feed-In Tariff system, is making them unprofitable- there's 6.8GW of wind capacity in the region. For these gas plants to be profitable, they need to run between 1,000-3,000 hours/year. In 2010, they only ran for 500 hours each at full load. And in 2011 they only ran for about 50 hours each, in grid balancing mode. In terms of reducing emissions, that's good news. But given the variability of wind, it's vital to have back-up available, or some other balancing measure.

Standard CCGTs can do it, but are less efficient when operating at low power- so you use more fuel/get more emission/kWh produced net, adding to operating costs and undermining the emissions saved by using wind very slightly. But the new generation of more flexible gas plants, like Alstoms GT24/ GT26, and GEs' FlexEfficiency 50, are more economically and environmentally attractive- they can ramp up and down rapidly with few emission penalties. For example, Alstom's unit can, it is claimed, run at 20% output but only produce about the same CO2/ kWh as when at full load, and can ramp back up to that in 3 minutes with little loss in efficiency. GE's unit can, it is claimed, ramp up at 50MW/min, twice as fast as conventional CCGT plants.

The UK next?

Germany is hitting this problem now since it has so much wind power capacity on the grid (27GW), but it seems that the problems mentioned above are limited so far: most of its CCGT are coping well, although new gas plants are planned, presumably with better flexibility.

The UK only has around 6GW of wind capacity in total so far, but aims to build a lot more offshore, maybe 18GW. So we will then face similar issues. No doubt in anticipation of that, Scottish and Southern Energy is to convert over 1400 MW of its gas-fired power generation to make their operation more flexible. The government is also planning to introduce a scheme that may help make back-up operation more economic. The new 'Capacity Payments' system, proposed as part of the Electricity Market Reforms, will offer contacts to generators who can help balance the grid with flexible 'peak power' capacity or energy storage, or demand reduction measures.

Nuclear plants can't with help that much. They are usually run 24/7 to recoup their large capital costs and there are operational and safety reasons why they cannot be run up and down from high to low power regularly and rapidly. It is not just thermal stresses, but also the excess production of contaminating isotopes, which, if the plants are cycled rapidly and regularly, can interfere with their efficient and safe operation.

The French PWRs do load follow to match daily demand cycles, as do the PWRs and BWRs in Germany. But their ability to ramp up and down over a wide range and regularly is relatively limited. New technology might in theory improve on that. According the EDF, it seems the new EPR reactor could ramp-up from 25% to 100% capacity, at 5% per minute of its maximum output (i.e. 80 MW per minute) e.g. from 400 to 1,600 MW in 15 minutes, but only 100 times per year e.g. once every 3 days.

That would not be much use for balancing regular wind variations, but might be useful for long lulls in wind, if the nuclear operators will also accept running at lower power (and losing money) when there is wind available. However, this may be irrelevant in that, under the terms of the UK's Generic Design Assessment, to which the proposed new nuclear plants have been subject, there are evidently no provisions for nuclear plants to load follow or be used for balancing wind power. That may of course change, but as it stands, the new Capacity Payment system looks likely to be use available mainly to conventional flexible back-up plants and energy storage facilities.

So the UK's eight new plants, if built, will be somewhat isolated from the emerging emerging flexible electricity system. That would surely have to change if, as new report from the Energy Research Partnership/National Nuclear Lab suggests is possible, we move on to have over 40GW of nuclear in place by 2050! www.energyresearchpartnership.org.uk/nucleartechnologyroadmap

Nuclear Problems

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The European Pressurised-water Reactor (EPR) being built at Olkiluoto in Finland is now unlikely to be completed until 2014- five years late- and $3bn or more over-budget. Similar problems face the EPR being built at Flammanville in France. And similar problems have emerged at the two 1.7GW EPRs being built at Taishan in China, 140km west of Hong Kong: variable concrete quality, unqualified or inexperienced subcontractors, poor documentation, language issues. Unit 1 is meant to be ready in 2013, Unit 2 in 2014, followed by two more. China has also had some problems with rapidly deploying its re-engineered version of the Westinghouse AP1000, but there are reports that it may be interested in a revised version of the EPR. Indeed some reports say that EDF may ditch the current EPR design for future EU plants and go for a cheaper, smaller, simpler franco-chinese design. All this has not helped the industries finances: French nuclear company Areva has operating losses of between €1.4bn and €1.6bn, the first loss for the 10-year-old group.

Matters were not improved by the report in January from the French nuclear power watchdog ASN, which, in its post-Fukushima review, said that EDF must install flood- proof diesel generators and bunkered remote back-up control rooms at its 19 plants across the country, at a cost of perhaps €10 bn,. Overall EDF estimated the cost of extending the lifespan of its nuclear plants from 40 to 60 years at €40-50 bn over the next 30 years. ANS didn't call for any plant closures and EDF was bullish, claiming that it invested 'more than €11 bn a year across the world.' However it has decided to diversify its nuclear-dominated portfolio by building strong businesses in gas and coal, as well as hydropower and renewables. But its shares fell a further 4.06% after the ANS review.

However nuclear faces more than just technical and economic problems, but also significant political shifts. In addition to the German, Swiss and Italian decisions to abandon nuclear, in France the Socialist candidate in the presidential election wants to cut nuclear by 50% by 2025 -the party has secured agreement with the greens to campaign for the closure of 24 nuclear reactors by 2025 in the election, though the Greens would prefer a 100% shut down. And in Belgium political parties seeking to form a government (it did not have one for over a year!) conditionally agreed to revert to the original 2003 plan to shut Belgiums three oldest plants in 2015 and the remaining two by 2025. Meanwhile a new tax has been imposed on nuclear operators. They currently supply 55% of Belgium's power.

In Japan, only five plants are still operating, out of the original 54, and three of them are scheduled to shut for annual maintenance and safety checks in April. With local opposition very strong and growing, it may be hard to restart them, or any of the others- they need the local municipalities to agree to that. So Japan may end up becoming nuclear free by default. Certainly long term nuclear looks like to be very constrained. In January, Japan's new prime minister, Yoshihiko Noda, said that Japan's dependence on nuclear power must be reduced to the 'maximum extent.'

The UK keeps going

There are no visions (yet) anything like that in the UK: indeed, in what some might see as a reversal of its policy on nuclear subsidies, the government has offered Sheffield Forgemasters a loan of up to £36 million "to continue its drive into civil nuclear and steelworks plant production." A similar offer had, you may recall, been withdrawn earlier.

Horizon Nuclear Power- a 50/50 RWE nPower/ EOn UK joint venture - plans to submit a planning application for a new plant at Oldbury around 2014. They say 'given the right market conditions, and subject to a final investment decision, preliminary works could begin in 2016, followed by main construction from 2019.' They have also bought land for a proposed new plant at Wyfla, with a planning submission scheduled soon, and operation by perhaps 2020. But they have yet to decide whether to go for Areva's EPR or Westinghouse's AP1000 for these sites. However, EDF and Areva have been pushing ahead with their plans to build EPRs at Hinkley and Sizewell: they submitted a site licence application for Hinkley Point C last July. And despite SSE pulling out of the consortium, NuGen is still planning a plant alongside Sellafield, with a possible 2023 start up date.

Will the nuclear plants really happen? EDF Energy is the most advanced so far. It said that before it finally committed to a go ahead it was imperative that 'transitional arrangements for the Contract for Difference are in place, arrangements for the funded decommissioning plan are set, and, we have a high level of confidence in the cost and timetable for construction.'

Although they have not given hard dates for the Sizewell and Hinkley projects, they originally said they wanted them to begin operating by the end of 2017 and in 2019 respectively. Fukushima and the need to extend the Generic Design Assessment process may have altered that but, though they have talked of an 'adjusted timetable', EDF have stressed that 'an adjusted timetable has never meant a suspended timetable, the project continues. It is on track.'

Longer term

With uranium fired reactors out of favour after Fukushima, for the longer term, some in the nuclear lobby have been promoting thorium as an allegedly safer fuel- looking at molten flouride salt systems.

The Weinberg Foundation was launched last year to promote the Liquid Flouride Thorium Reactor (LFTR) which was portrayed as one of 'the world's safest reactor designs which cannot burn or melt down, breeds its own fuel, consumes most of its highly radioactive products, and will not release any radioactive materials into the environment'.

Canada, China and India all have projects underway but the technology is still some way off as viable commercial option. Certainly it's not without its problems. Thorium is not fissile, so to make a reactor work you have to mix it with U235 or plutonium or provide some other source of neutrons (e.g. a particle accelerator) to convert it to U233, which is fissile. What you then get, as well as heat energy, radiation, and fission products from the Plutonium and Uranium, is U232. U232 (and its decay products) emit very hard gamma radiation. That's seen as ensuring that no one would try to steal fuel from thorium reactors to make bombs - since it would be so hard to work with or shield from detection. But it also makes it hard to design safe reactors or deal with their wastes- you need very much thicker shielding for the reactor core or for waste transport containers. We are probably talking a meter of lead or so!

Some thorium enthusiasts say that nearly all the wastes can be burnt up within the reactor, but there will still be some to deal with- and there's always the chance of fuel/waste escapes/ leaks. And you really wouldn't want to be around then.

So will it happen? Should it? The LFTR may be better than the current range of uranium designs, but it will be a while before we know for certain- there's a host of unknowns and risks. Friends of the Earth seems content to leave it as a possible long term option, and certainly it's an argument against rushing into a new wave of current types of reactors. But will anyone really trust the nuclear lobby when it says 'we have the answer', as so often before? Technologies like this also seem to attract single-minded lobbyists and believers in 'silver bullet' fixes, which can distract from the development of a wider range of arguably more realistic renewable options.

For a different view see: www.theecologist.org/blogsandcomments/commentators/othercomments/962512/responsedontdismissthepotentialofthorium nuclear_power.html

In my next Blog I'll look at the prospects for nuclear in the developing world- some see that as its best hope.

This week saw BBC Radio 4's Material World dedicate almost the first half of its weekly science update to Earth and environmental research.

First up was Martin Siegert of the University of Edinburgh, UK, speaking on the recent breakthrough into Antarctica's underground Lake Vostok by a Russian team drilling through the ice. Siegert is leading a rival group investigating Lake Ellsworth on the other side of the continent.

Next was Judah Cohen from Atmospheric and Environmental Research, US, talking about his paper in Environmental Research Letters on the link between Arctic warming and colder winters in North America and Europe. According to Cohen, higher temperatures in the Arctic have melted sea ice, enabling more moisture to enter the atmosphere. In turn this tends to increase snow cover in Siberia, which appears to be associated with colder temperatures in eastern North America and northern Eurasia.

Listen in to the show to find out more, it should be accessible worldwide. The cold winters interview starts after 7 minutes 33 seconds. If you carry on listening you can hear a discussion on whether Freud was a scientist and news of the launch of LARES, the Laser Relativity Satellite that will test Einstein's theory of gravity.

You can also read a news story about Cohen's paper.


Wind Balancing

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The debate over how much back-up capacity is needed to balance wind variations continues. Everyone agrees you need some, but some say you need 100% and that, as a result, wind power won't save many or, even any, emissions, net. See for example: http://environmentalresearchweb.org/blog/2011/11/does-wind-power-reduce-carbon.html

There is, in this debate, usually a confusion between, firstly, short term balancing (which is done all the time, even without variable wind on the grid) to deal with occasional unexpected plant or grid trip-outs and the daily demand variations, using frequency adjustments and by winding-up power from 'spinning reserve' plants; and, secondly, longer term possibly larger and longer loss of power issues, when you may need to crank up extra plant to meet gaps, calling on the built-in extra plant margin that grids have for this purpose.

For the moment, most grids can cope with the amount of wind linked in relatively easily, as many reports have indicated. The latest, 'Strategies and Decision Support Systems for Integrating Variable Energy Resources in Control Centers for Reliable Grid Operations', produced by Alstrom for the US Dept of Energy, offers first- hand perspectives on how variable energy sources, including wind, actually impact grid operations. It finds that the ability to forecast variable energy output is vital to integrating variable energy. It also describes several decision support tools that are currently used by grid operators. http://energy.gov/articles/new-report-integrating-variable-wind-energy-grid

But some extra fast start-up back-up, and maybe extra marginal gas plant, may be needed as the share of variable renewables grows. Key roles can also be played by other grid-balancing strategies, e.g. smart-grid interactive demand management and importing power from other countries via HVDC supergrids.

Alstrom's US report does note that upgrading grid transmission links is a key long-term requirement - not least to deal with the perhaps more relevant problem of how to deal with excess power from wind and other variable renewables.

All that said, you will still find substantial contrarian assertions (e.g. from the US energy collective.com and the North American Platform against Wind Power: www.na-paw.org) that the variability of wind is an unresolvable issue. Similar lines of attack have been adopted by some UK centre-right think tanks, most recently by CIVITAS.

Much is made of the large and rapid swings from full power to low power that can occur, despite the fact that grids already deal with large demand swings daily. True, the existing swings are usually predictable, which is why the US Alstrom report looks to improved wind forecasting. But, while there's no one solution, given smart grids/DSM and storage plus supergrid imports, it should be possible to balance even large variations- though it may be harder in the US, where cross national grid links are weaker and there's less gas/CCGT, although of course shale gas may change that.

Back in the UK, we have a good well integrated grid system and last year a Poyry report for the Committee of Climate Change spelt out how it, and some upgrades and extensions, could help us balance some 'stretching but feasible' scenarios with high levels of renewables (reaching up to 94% in the Max scenario).

They found that 'the electricity system was able to accommodate these high levels of renewable generation whilst complying with the specified constraints on emissions and security of supply. However, this was at the cost of shedding low variable cost generation and construction of new peaking capacity; predominantly in the two 2050 scenarios and Max scenario'.

Shedding power (or 'curtailing' excess output) is wasteful, but building new low cost gas-fired capacity is relatively cheap, and they say, not urgent 'Construction of peaking plant is not required until after 2030 in either the VeryHigh or the High scenario'.

Overall they say 'Sufficient technical resource appears to be available to deliver very high levels of renewable penetration', but if offshore wind then dominates, diversity is reduced making grid balancing harder. So they are keen on a wider range of renewables being used.

So how robust is their projected future renewables-based system? They report that their scenarios were also tested against 'more extreme weather conditions, as defined as increased frequency of low wind periods ('lulls') and greater variability of wind output.'

They say 'In our (very) high renewable scenarios, we found that there is relatively little difference between the level of security of supply...in an average weather year and from the level in one of our extreme weather years'. But 'CO2 emissions increase in the year with more lulls because fossil fuel plants run at higher load factors to compensate for lower wind output. In contrast, there is a (slightly) higher average annual load factor for wind in the more variable wind year. This leads to lower emissions, particularly in 2030.'

For the moment there should be no major problems, but we will need to act later; 'The closure of unabated gas plants will reduce generation flexibility by 2050': while in 2030, the electricity system is able to accommodate high levels of renewable penetration 'in 2050, around 40TWh of low variable cost generation is shed in the High and Very High scenarios, with a need for new peaking capacity of 6GW and 10GW respectively'.

The situation is even worse in the Max scenario when 'shedding increases to 120TWh a year, and 21GW of new peaking capacity is required to meet the desired level of security of supply. This is despite an assumed increase in demand-side flexibility and an expansion of interconnection capacity between 2030 and 2050 (and between 2050 and the Max scenario).'

So in addition to grid extensions and demand side management, after 2030 you also more peaking plant., although they add 'a more diverse renewables mix helps the system to accommodate high renewables. Increasing the deployment of solar and tidal range (and reducing offshore wind deployment) in the High scenario leads to a big fall in the amount of shedding and required new capacity build in 2050.'

They say that, although it in basically inflexible, nuclear might also play a role: 'despite the increase in shedding, construction of nuclear capacity is still cost-effective given the assumed set of fuel and carbon prices and generation costs', but they add, 'alternatively, interconnectors could be used to provide GB with access to a more diverse renewables mix in Europe'.

We do seem to have plenty of options. And Pyorys analysis does seem to be an answer to all those contrarians who say renwables can't do it , though some still say ramp-up rates will be high, and hard for existing peaking plant to cope with. The debate continues

Pyory report 'Analysing technical constraints on renewable generation to 2050', to the CCC, March 2011

The mismatch between insight on the need for climate change mitigation and implemented policies is amazing. Seemingly, this is a particularly hard global common good problem. So why not push much harder for pure win strategies. Pure win strategies often lack the intelectual appeal of a global cap and trade and, for being so nitty-gritty, put less glory on policy makers. But they can be valuable entry points for global cooperations. Here is one example.

Diesel fuel reserves tax benefits in most Asian countries, and is favored in vehicle regulation. At the same time, pollution control is weak at best. At a result, vehicles powered by diesel emit tons of black carbon in addition to CO2. Black carbon is the third most gaseous contributor of climate change and has most of its climate impact on short time scales (more like 20 years), whereas CO2 remains in the atmosphere for more than 100 years in average. Black carbon and other diesel exhaust also pollutes the air breathed by billions of Asians, causing asthma and lung cancer.

Here is the strategy as developed by Minjares and Rutherford (both from ICCT, San Francisco) in the upcoming book "Low Carbon Transport in Asia" by Zusman, Srinivasan and Dhakal:

  •  Make particle filter in diesel vehicles mandatory. This can dramatically improve air condition for Asian city dwellers in the upcoming decades. Even more, this single measure can reduce GHG emissions by 14% on a GWP20 basis and by 4% on a GWP100 basis. Not the killer app, but considering the huge health benefits, this is a straight forward measure.
  •  Switch to carbon-neutral fuel emission standards (i.e. corporate average, not weight-based, and I would insist, also not size-based). Asian countries can rely here, as well as for pollution control, on the well-established technological advance from OECD countries. No need for R&D investments here.
  •  Finally, tax benefits for diesel vehicles can be scrapped, and taxation can follow the GHG content of fuels only.

These measures require some institutional capacities, but not much financial resources from governments. That is probably where industrial countries or the Asian Development Bank can come in with support. But Asian countries profit most, besides climate mitigation, improving public health conditions drastically, especially for the poor, and raising tax revenues simultaneously.  

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