Renewable Energy: Vision or Mirage?

December 15, 2011 | 00:00

Renewable Energy: Vision or Mirage?

There have been many studies on renewable energy technologies in recent years, both from a UK perspective and elsewhere. Some cover a rather narrow aspect, a number present a somewhat one-sided view, and most focus on a single source of energy, generally wind.

We have attempted something broader: to review the information available on the range of current and emerging renewable energy technologies and summarise the present position and potential contribution of each one. In doing so, we have tried to be objective and make judgements solely on the information available.

The conclusions may not be very palatable given the current political enthusiasm for renewable energy. However, facts are facts and we believe strongly that policy should have a good chance of achieving its goals in a cost-effective way, and also be guided by evidence. Governments are elected to lead, but they also have a responsibility to spend taxpayers’ money wisely. Moreover, they have an obligation to the electorate to provide a secure, affordable supply of energy, on which economic competitiveness and the safety and comfort of citizens depends. The evidence shows that continuing along the current path will not do this and certainly does not represent an efficient use of tax revenues.

The authors are grateful to all those who have provided material for this report and commented on drafts. We particularly appreciate the constructive reviewing of Colin Gibson and John Scott. The final report represents the views of the authors and we are wholly responsible for whatever errors and omissions remain.

Executive summary
1. EU and UK national government policy is driving a move towards progressive replacement of fossil fuels (coal, oil and gas) by renewable energy sources and nuclear power. However, with a few notable exceptions (hydro power in Norway, geothermal energy in Iceland, for example) available renewable power technologies are neither economically competitive nor easily capable of providing the degree of energy security demanded by a developed society.
2. This report reviews the options from a technical and economic standpoint and assesses the real contribution they can make to a future secure, affordable energy supply. At the same time, we consider the efficiency with which they can achieve one of their primary objectives: to reduce emissions of carbon dioxide.
3. We conclude that the renewable energy technologies which are commercially available or in development cannot form more than a minor part of the overall mix without putting the security of supply at jeopardy. The need for increasing amounts of conventional backup capacity as renewables form a larger part of the overall mix severely limits their contribution to emissions reduction.
4. On-shore wind is the lowest-cost option, but still requires financial incentives to encourage investment and has limited scope for expansion because of public opposition and lack of appropriate sites. Its viability would be reduced even further if developments had to carry the cost of the additional gas-fired generating capacity needed as backup. 28% of Ireland’s installed electricity generating capacity is in the form of wind farms, but only 13% of power consumed was generated by wind in 2010/11. UK capacity factors are lower.
5. Experience from other countries with larger percentages of wind generation shows that only limited savings can be made in fossil fuel consumption and that security of supply can only be guaranteed by having a large-scale backup capability or a high degree of interconnectivity with neighbouring countries having surplus capacity. Wind farms supply only about 10% of Danish electricity consumed, despite generating more than double this.
6. Burning of biomass to generate electricity has some merit and may be economically competitive as fossil fuel prices rise. However, its relatively low energy density increases transport costs, and in practical terms it can never make more than a minor contribution to the overall energy supply. To meet DECC’s targets for the UK, by far the greater part of the biomass would have to be imported. For example, UK-grown straw could generate less than 2% of the country’s electricity needs.
7. Solar power – the most expensive of currently available technologies – has little contribution to make in northern Europe. Germany has become the world’s leader in solar cell installations, paying billions of euros annually to provide just 2% of the country’s electricity from photovoltaic panels with a capacity of 17GW but which operate at a capacity factor of only about 10%.
8. A high contribution from intrinsically intermittent renewable power generation without matching conventional capacity as backup – even if demand and supply were to be better balanced via a Europe-wide grid – would require affordable and reliable large-scale energy storage capacity capable of providing backup over a period of days or weeks. No technologies capable of providing this exist or are in development.
9. The economically extractable supply of fossil fuels is not infinite and our dependence on them must inevitably decrease as their real price increases and viable alternatives are developed. Some public support will be needed to bring these new technologies to market. However, governments are currently indulging in the dubious practice of providing guaranteed, long-term subsidies to technologies which have little hope of becoming truly competitive for the foreseeable future.
10. In the meantime, taxpayers’ money would be far better spent on measures to increase energy efficiency, plus investment in proven nuclear and gas generating capacity to provide energy security as many of the UK’s coal-fired stations – and nearly all existing nuclear reactors – are decommissioned over the coming decade.
11. Neither can we ignore the possibility of building new coal-fired stations, or commercialising underground gasification, to make use of the large reserves of coal in the UK and other European countries, which could
contribute to energy security for many years to come.

To acces the full report, click here.

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