Heat of the moment

The government is poised to publish its first-ever heat strategy. And not before time, most observers believe. Heat accounts for more than half of the UK’s energy demand yet it remains the Cinderella of the energy debate – central, but often ignored. Unless UK plc gets a real grip on reducing the carbon footprint of heat use, we can wave farewell to the country’s ambitions for decarbonising the economy.

The government has set a challenging carbon reduction target for 2050 and is currently working towards the European Union target to increase the share of renewable energy to 15 per cent by 2020. Current high-level modelling and scenarios suggest that meeting these targets will require increased energy efficiency, decarbonising generation and expanding the use of electricity into heating and transport.

In a nutshell, the prospect of a more electric-­centric future looks to be shaping the direction of policy, which is already beginning to encourage the uptake of low-carbon heat via measures such as the Renewable Heat Incentive (RHI). There are, it must be said, big questions marks over the immediate future of the RHI. Its domestic rollout, due later this year, is looking, to put it mildly, uncertain.

That said, the emerging picture is that between 2020 and 2030 the demand for gas will decline while the demand for electricity will rise significantly, partly reflecting the uptake of electric heat, which domestically looks as though it will focus initially on new-build housing and off-gas households.

After 2030, the projections are that renewable heat will also significantly penetrate the on-gas housing market. Is that either credible or feasible? What will prompt gas consumers to switch from gas as their technology and fuel for heat? There is, frankly, a big gap between where consumers are now and where the modelling and policy suggests they will be post-2030 (see feature, page 20).

Although total domestic demand for gas appears to have peaked, its use still dominates final energy consumption. Currently, gas accounts for around 84 per cent of total household energy consumption, meeting around 83 per cent of space heating demand, 78 per cent of hot water demand and 52 per cent of

cooking demand.

Last year a study by the Energy Policy Group at the University of Exeter, commissioned for Scotia Gas Networks, questioned the “aspirational level” for electric heat implied by the UK’s carbon targets. The researchers suggested that policymakers should pay more attention to improving the efficiency of on-gas households. “This could include upstream measures to reduce losses and make more use of biogas as well as the very considerable downstream scope with respect to replacing inefficient boilers, installing better controls and supporting the development of new technologies,” they argued.

Recent comments from energy minister Charles Hendry and his new boss, energy secretary Ed Davey, suggest that the role of gas for heating has become a hot topic politically. The strategy will need to be very clear in this area and realistic about consumer preferences and drivers. Encouragingly, the Department of Energy and Climate Change (Decc) has drafted in consumer expertise and some social scientists to help inform the strategy. But it remains to be seen how their input has shaped the exercise.

Clearly, any heat strategy will also have to address the potential contribution of combined heat and power (CHP), district heating schemes and heat networks in urban areas (see feature, page 18).

The Combined Heat and Power Association recently published a report (Heat Revolution: Putting Consumers First in a Decarbonised Economy) which it says provides a credible pathway for the decarbonisation of heat. This assessment looks at the technologies and the network requirements involved: these range from the development of local bioenergy solutions, wholesale distributed generation, a key role for biogas, smart grids, district and community heating schemes, the deployment of heat pumps, large-scale heat stores and the development of industrial clusters of intensive energy users utilising high temperature heat networks.

Pie in the sky? Well, the report indicates individual examples of these elements. What it highlights is the current lack of integrated thinking. Co-ordinated activity is required from a range of players (heating equipment manufacturers, local authorities, developers, industry and energy companies) and a daunting list of government departments, not to mention energy regulator Ofgem.

It also signals that financial incentives, light-touch regulation and a helpful and an accommodating planning regime will be needed.

All that adds up to quite an ask for the strategy.

Roger Milne is political and environment editor

Heat pump posers

Modelling work and scenarios from both Decc and the Committee on Climate Change suggest there will be only a limited role for biomass and solar thermal in the domestic sector initially. But both seem persuaded that the use of heat pumps will grow significantly, indeed almost exponentially. The present installed base of around 30,000 units is expected to become 600,000 by 2020 and 6.2 million by 2030, rising potentially to up to 27 million by 2050.

A lot appears to be hanging on a technology that in the UK has so far had significant and well publicised problems meeting expectations. There are network issues, too. High concentrations of heat pumps will increase the level of reactive power on the networks, which could require investment in larger cables and transformers. It’s a moot point if the existing price control regime is up to the task.

Work in mainland Europe is showing that “smart” operation of heat pumps can help balance generation and demand and manage network congestion. In Germany, Vattenfall has launched a virtual power plant to control the operation of heat pumps and CHP units according to wholesale market power prices. Vattenfall owns the units and sells their heat to households who can override the dispatch schedules if “end user comfort levels aren’t being met”. The scheme will serve 100,000 homes and involve 500MW of energy.

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

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