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Tag Archives: Denmark

All change in Germany, the EU, and the US?

By Dave Elliott

Things are changing in Germany. With renewables booming, German energy giant RWE has suffered a massive loss of €2.8 billion, its first loss in 60 years. It has admitted it got its strategy wrong, and should have focused more on renewable and distributed energy rather than conventional fossil fuels: ‘We were late entering into the renewables market – possibly too late.’  A previous RWE CEO had gone on record with the immortal line: ‘Photovoltaics in Germany make about as much sense as growing pineapples in Alaska’.  www.reuters.com/article/2012/01/18/germany-energy-idUSL6E8CI12Y20120118

Now Germany has 36.5GW of PV, supplying around 5% of its electricity and at peak times much more!  And about 8% from its 33GW of wind.  (more…)

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Scotland – isolated or leading?

By Dave Elliott

It has been claimed that if Scotland goes independent of the UK it will find it hard to sustain its ambitious renewable energy programme, which aims to match 100% of Scottish electricity use from renewables by 2020. It already gets over 36%, but that expansion has partly been due to the support of the UK-wide Renewables Obligation, which passes on the cost to all UK electricity consumers. The income from just Scottish consumers (10% of the UK) would clearly be much less. A report by Dave Toke and others, “Delivering renewable energy under devolution”, published in Political Quarterly, says that “funding a significant expansion of Scottish-based offshore renewables under independence would lead to considerable increases in Scottish electricity prices, something that a Scottish government would find hard to sustain politically”.

However it is not clear whether, after independence, it would come to that. The new (lesser!) UK would need the Scottish projects to meet its renewable-energy targets, if they were still to be retained, so the new UK would have to continue to support Scottish projects, new and old. The Scottish government said that it “believes the current, integrated GB electricity market should continue post-independence, as it’s in our mutual interests. Given Scotland’s vast renewable resources, with independence, it will be in the rest of the UK’s overwhelming interests to ensure support arrangements are in place to secure Scottish renewable energy”: www.politicalquarterly.org.uk/2013/02/scotland-renewable-energy-and.html

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A History of Energy

By Dave Elliott

Bent Sorensen, a leading Danish alternative energy pioneer, who wrote a seminal and massive text book on ‘Renewable Energy’ and many other important research papers (see http://energy.ruc.dk. It looks in fascinating detail at the history of energy production and use, mainly in Denmark, from the stone age to the present day, linking that to social, economic and political developments and influences. So we move through early pre- history, the middle ages , the industrial revolution, the second world war and then on to the more recent battle against nuclear and the dramatic growth in the use of renewables.

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Denmark: good or bad for wind power?

Wind power enthusiasts sometimes point to Denmark as a good example of what can be done- claiming that it gets around 20% of its electricity from wind. Wind opponents also sometimes point to Denmark, claiming that in fact not much of this is actually used in Denmark since it’s often available at the wrong time, when demand is low, and so has to be exported. Worse still, Denmark has to import power (mainly from hydro) from Norway and Sweden, to back up it’s wind plants when they can’t deliver enough and demand is high. This costs them more than they get from their exported wind. So wind is a net financial loss, and a drain on the Danish economy. A debate on this issue has been raging on the Claverton Energy Group website and e-conference over the past year.

Some say it’s all because Denmark has a small, inflexible energy system. It’s been pointed out that a major effort was made in Denmark to move away from oil over to coal. Much of the coal capacity consists of large centralised Combined Heat and Power (CHP) plants, which although more efficient that conventional electricity plants, can’t easily be used to balance the variable wind output. Worse still, heat is often needed when there is no major demand for electricity. In these circumstances some CHP electricity has had to be exported, along with any excess from wind. Unfortunately this will be when there is likely to be a surplus of wind power in the surrounding countries, so the price which is offered is quite low.

Against that, these exports will be reducing the amount of fossil fuel which is used in places like Germany. In Norway and Sweden though this electricity may sometimes only be replacing (zero carbon) hydro, but that depends on the timing – if their hydro reservoirs are low, it can be used to pump them up, in effect storing wind power and excess CHP power for later use. On this view all is well in climate terms, though it does cost the Danes more: what’s really needed is a pan-EU balancing system, with perhaps a Cross Feed tariff to ensure that using stored power in not prohibitively expensive. More flexible generation/load management in Denmark would be good too. Along with better interconnections- and an economically synchronised market system covering all the participating and connected countries (e.g. the Baltic states and Germany). Certainly, some say that Denmark is too small to be treated as a coherent energy system, but others say that being small is actually a great advantage for them, it means that wind can be backed-up (via interconnectors) by larger grid neighbours – something that would be much more difficult in UK’s case.

Lessons for the UK

Some argue though that, being larger with a range of flexible back up plants, the UK could in fact do much better than Denmark – although they accept that it must strengthen its grid and interconnections. But even without much of that, there should be no need for extra backup for some while: you could add 30 GW wind and use existing UK fossil plants as back up – you don’t need to build 30 GW of new plant and therefore “pay twice”, as some anti-wind people claim. We already have it – and have paid for it. And some of it is already used as back-up – for conventional and nuclear plants, and to deal with the daily demand peaks. On this view, basically, when available, what wind power does is replace some output from the existing power system – so you don’t need to build any extra back-up for when wind is not available.

Although the probability of zero wind output is relatively low, as things stand at present, we would have to retain all, or most of, the existing system – wind has a low capacity credit, perhaps 15% depending on the total capacity. However, more existing capacity could be retired if we had a more flexible system, with more load management, more storage and more interconnections, plus inputs from firm non variable renewables like biomass and geothermal, though the optimal mix is as yet undetermined. There is also the problem that operating fossil plants occasionally at lower power means they are run inefficiently, part loaded, which adds to costs. But they may not have to run often and the cost penalties will therefore be low. Inputs from other renewables could also help (e.g. although they are variable/cyclic, wave and tidal availabilities are phased differently from wind). Inflexible nuclear however just gets in the way. At least Denmark doesn’t have that problem!

You can join the debate at www.claverton-energy.com.

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