Who’s in charge?

Who should lead our power and heat decarbonisation strategy - the market, the government or others? Matthew Leach reports on academic modelling of the options.

The decarbonisation of the UK is running fast on a single set of rails: electrification. Electricity is predicted to be everywhere: with the power sector shifting over to renewables (largely offshore wind), new-build nuclear and possibly carbon capture and storage; and electric space heating (primarily through the use of heat pumps) set to be an integral part of transforming buildings and their traditional role as carbon emissions ­villains.

However, an electrified future brings new risks and uncertainties. There will be many and complex problems for consumers, for instance. Assumptions of mass uptake of heat pumps seem to ignore strong practical barriers such as that siting air source heat pump exchangers in the small but precious backyards of the country’s enormous Victorian terraced housing stock would face stiff opposition.

The future of heating is in practice likely to be – and should be – more diverse than recent studies assume. Electric heating will have a role, but there should be roles too for further combined heat and power, district heating networks, bioenergy, biogas and truly zero-heating new build.

Work at the Centre for Environmental Strategy at the University of Surrey in partnership with a consortium of other UK universities has mapped the likely implications of taking different pathways to a low-­carbon economy. We looked at three pathways to 2050: market rules (a market-led pathway); central co-ordination (a government-led pathway); and a civil society-led pathway. All lead to a high degree of electrification, particularly in the transport and heating sectors. The work also identified a number of other key findings.

In terms of energy demand for space and water heating in domestic properties, demand is reduced by 31 per cent under market rules, 33 per cent under central co-ordination and 37 per cent under civil leadership – all despite a 30 per cent growth in the number of households.

Peak levels of demand can be very high – up to 83GW under market rules and up to 66GW under central co-ordination for the year 2050, but only 38GW in the civil society-led scenario, compared with 57GW so far this winter.

In all three pathways, a significant amount of generating plant has to operate at very low capacity factors (less than 10 per cent) because fossil-fuelled power stations are held in reserve to back-up intermittent renewable generation: 32GW in market rules, 26GW in central co-ordination and 17GW under civil leadership. All three pathways also result in significant electricity surpluses, arising from high wind power generation occurring at times of low demand. These peak at 19GW (market), 15GW (central) and 44GW (civil).

Time-shifting demand to off-peak periods or when renewable generation is plentiful, either through automatic controls or encouraging behaviour change, has strong benefits. In all three pathways it would reduce peak demand by about 10GW. The research only included time-shifting of demand by a few hours. Other measures such as dynamic shifting of demand between electricity, gas and liquid fuels, according to the availability of electricity, could make much greater reductions in variation in net electricity demand, and there is much potential for future innovation in smart homes and networks.

The market-led pathway does not quite achieve an 80 per cent reduction in carbon dioxide emissions by 2050. Other mitigation measures may be necessary such as more hydrogen production for use in transport, and greater use of biomass energy. The other pathways are predicted to achieve an 80 per cent carbon reduction but may not quite achieve an 80 per cent reduction in all greenhouse gases without further measures.

All three pathways result in an increase in the total amount of energy the UK must import in the coming decades, from about 300TWh to 500TWh or 1,000TWh a year, with market rules again being the pathway with the greatest demand.

Matthew Leach is a professor and director of the Centre for Environmental Strategy at the University of Surrey. The full research paper is to be published in Energy Policy journal

This article first appeared in Utility Week’s print edition of 30 March 2012.
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