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Green Heat

Sensible U.K. government subsidies could unleash some serious carbon-cutting potential in the British market and beyond. By Matthew Spencer

Gas prices soar, the U.K. Meteorological Office forecasts a cold winter, and here we go again with the dire predictions of fuel shortage. There isn't enough gas to keep us warm and keep the lights on. Reach for your candles, the dark day of the 1970s blackouts are here again.
It doesn't have to be that way, if we'd only get serious about green heat. Wood fuel boilers, solar water panels and ground source (geothermal) heat pumps are relatively cheap to run. If we used these readily available technologies instead of gas-fired boilers, and took sensible steps to reduce the heat leakage from our homes, there'd be plenty of gas left to keep our power stations working.

Unfortunately, renewable heat remains the poor cousin of renewable electric technology. There’s no government target, and no subsidy mechanism to get it to market.

Why this neglect? Because demand for heat is driven by local markets; green heat (unlike green electricity) is not tradable on a large scale, and the U.K. market is dominated by small companies. The government can handle electricity because it is a national commodity with a few big players, but it has pigeonholed green heat in its narrow view of "community renewables." Nice for the village hall, but not a serious contender.

The experience is very different elsewhere in Europe, where green heat technology is supplying commercial quantities of energy. Geothermal heat pumps alone are delivering two million metric tons of oil equivalent a year in the EU, and large offices in Scandinavia are now reversing the heat pump process and using boreholes to provide summer cooling as well as winter heat. There are now concerted moves in Brussels to develop a renewable heat directive -- and organizations as diverse as the International Energy Agency and Greenpeace are supporting the call for up to 25% of heating and cooling demand to be met by green heat by 2020.

The support that green heat needs to get to market is not great. A subsidy of around one penny per kilowatt-hour would be enough to see this sector take off, with its high conversion efficiency compared to electric technology, combined with high oil and gas prices. That’s just a third of the cost of the Renewable Obligation buy-out. One way forward might be a renewable heat obligation on energy utilities and other suppliers of conventional heating -- but the jury is out on whether this is feasible in a very fragmented market. Another possibility would be to give green heat consumers a credit for each metric ton of carbon they save, which they could cash in via emissions trading arrangements.

Our approach to green heat in buildings has to be led by a program of reducing energy use, since this is where the biggest carbon savings occur. In new buildings this can dramatically lower heat demand. It is now possible to eliminate the need for space heating altogether through the use of super insulation and passive solar design. Nevertheless the need for water heating remains. In many offices the need for cooling is also unavoidable. This is a massive growth area in energy use, and the use of ground source heat pumps in reverse is an attractive emissions-free alternative to conventional air conditioning.

The biggest market for green heat is in existing buildings, where energy efficiency measures will never remove the need for space heating. This is where the majority of the nation’s gas is currently consumed, and where there is a huge opportunity to adopt green heat technologies.

If we are unfortunate enough to get blackouts this winter there will be a desperate clamor for new power stations and new gas pipelines. But this is the wrong answer. The real answer is not new power stations but fewer gas boilers. That can only be achieved by increasing insulation and by the uptake of green heat in our homes and offices.

Matthew Spencer is chief executive of Regen SW, the renewable energy agency for the southwest of England.

This column has been reprinted courtesy of Green Futures. It first appeared in the January/February 2006 issue of that publication.

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