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Give up in the UK?

‘Only a system with its base-load provided by nuclear power, supplemented by gas for peak demand, and retaining the existing wind investment, can possibly supply the UK long-term with the huge amounts of secure and reliable, predominantly electrical energy, it needs. To actually achieve a changeover to a largely non-fossil fuel economy without wreaking catastrophe on our industries, the targets set by the Climate Change Act 2008 will have to be pushed back no matter whatever combination of electricity generating technologies is built’. So says Prof. Stephen Bush from Manchester University, writing, with David MacDonald, in The Chemical Engineer, ICE’s magazine, last Oct.

This conclusion is reached in part by wheeling in the standard arguments about the low energy intensity and high variability of renewables and consequent large land areas needed. Is that so? It’s certainly a view widely promoted these days in the media. See my earlier ( New Year) Blog. http://environmentalresearchweb.org/blog/2011/12/new-year-wish—a-more-balanced.html

As I pointed out there, it’s been argued that PV can mostly be on roof-tops, so there is no extra land-use. With offshore wind, the land-use issue disappears, but variability is certainly an issue. The ICE article says ‘to store a week’s supply of electricity from the current 3,226 MW grid-connected wind capacity working at the annual average 25% load factor would require 4.5m m3 of hydrogen stored at 10 bar, or a lithium-ion battery stack 100 m2 by 34 m high. Extrapolated ten times to the 32 GW of wind capacity proposed in National Grid’s Gone Green scheme, it can be seen that this buffer storage concept to use wind power on this scale is another blind alley’

Whoever said we needed to be able to store a full weeks wind output? Some storage would be helpful, especially pumped hydro, but when there are local UK wind shortfalls, in addition to all the usual backup available from the rest of the grid system, what about importing power via a super-grid, shifting demand peaks by interactive load management, and using biomass-fired backup? It’s certainly going to be challenging to meet the targets, but that’s what targets are for- to set the pace.

However some say it will cost a lot. In Fraunhofer Institutes Working Paper S7/2007 on Sustainability and Innovation, Frank Sensfuß, Mario Ragwitz and Massimo Genoese look at the so-called ‘Merit-order’ effect, offering a detailed analysis of the effect of renewable electricity generation on spot market prices in Germany. It’s argued that when there is a lot of wind energy on the system, less generation is required from other sources. This cuts wholesale electricity prices, which reduces (non-wind) generator profits, but benefits consumers. It’s claimed that the overall savings is greater than the subsidy paid for wind. So the net cost of supporting wind can be negative. See also Awerbuch, S. and M. Berger, 2003 ‘Applying Portfolio Theory to EU Electricity Planning and Policy Making’, OECD/IEA, which comes to similar conclusions. www.awerbuch.com/shimonpages/shimondocs/iea-portfolio.pdf

That is not to say the initial capital cost will not be significant. The new report ‘Positive Energy’ from WWF, claims that renewable sources of energy could meet up to 90% of the UK’s electricity demand by 2030, but it notes that this may not be achievable in that time frame. Based on a series of scenarios produced by consultants GL Garrad Hassan, it concludes that the amount of renewable capacity the UK can build is determined by economic constraints - not available resources. Garrard Hassan assume that it’s economic to supply around 60% of demand from renewables. WWF say that going beyond 60% depends on whether there’s a market in other countries for the excess electricity the UK would generate at times of high renewable production/low demand. Therefore, given uncertainty over future markets, in the core scenarios, they do not assume a European market for UK renewable power, and they only have a 3GW supergrid interconnection.

By contrast, in the ‘stretch’ scenarios, it is assumed that interconnection creates a European market for the UK’s excess power, and that it becomes economic to build much more renewable capacity in the UK- with up to a 35GW supergrid interconnection. In addition to providing an export option, that provides a balancing option for when weather conditions across the country mean little power from renewable generation (like wind power). Otherwise that has to be done mostly using gas plant. However they say that, even then, decarbonisation targets could still be reached, with an ambitious roll out of CCS on a significant proportion of the UK’s gas capacity, but with CCS plant run at 80% of their load factor (capacity) and non CCS plant run at considerably lower load factors. Clearly though they would prefer a high levels of interconnection.

WWF says that the government must give investors enough certainty to be willing to make large-scale investments necessary in the UK renewables supply chain. It’s therefore called on the government to commit to a target of getting at least 60% of UK electricity from renewables by 2030. .

‘Positive Energy: how renewable electricity can transform the UK by 2030’ http://assets.wwf.org.uk/downloads/positiveenergyfinal_designed.pdf

Broadening the view to cover the whole EU, Power Perspectives 2030, phase 2 of the groundbreaking Roadmap 2050 report from the European Climate Foundation, looks at the key steps to power sector decarbonisation across the EU for the next two decades. It says that while the existing energy policy framework to 2020 represents an adequate first step towards the EU 2050 emission reduction goals, the decarbonisation process will need to accelerate significantly in the decade 2020-2030.

In what it labels an “on track” scenario, based on the EU managing fully to implement its plans up to 2020, and assuming there are projects in 2030 in line with targeted emissions cuts, it anticipates a power mix in 2030 made up of 50% renewable energy. The rest would include 34% fossil fuels, plus a further 8% abated by CCS, 17% by nuclear. After that could come a push to get to near 100% from renewables by 2050, as outlined in their original report, with nuclear phased out.

The ECF led the project with McKinsey, E3G, KEMA, and Imperial College: www.roadmap2050.eu/pp2030

The European Commission has come up with something similar in its new 2050 Roadmap, which aims to get to virtually carbon free electricity, and an overall cut in emissions of 80-95%, by 2050. So the UK will not be alone if it perseveres in seeking radical change.

Posted by Dave Elliott on January 21, 2012 1:42 PM | Permalink