Energy efficient

Renewables are not the only answer to achieving the government’s targets for reducing emissions. Wasted energy needs to be the next thing we address. Dr. William Nuttall reports.

The British government loves targets – health service waiting lists, youth justice, student numbers, the list is almost endless. Policy for the electricity industry is no exception.

The push for renewable electricity has long been visible. The government has set a target that by 2010 10 per cent of electricity generation should come from ‘renewables’, such as wind and hydroelectricity. As the UK is prone to windy weather, the dominant new renewable technology will be wind turbines, mostly located offshore. So it now seems likely that the government will hit its renewables target on schedule.

A second set of targets covers annual greenhouse gas emissions. As part of the Kyoto process, by 2008-2012 UK greenhouse gas emissions should be 12.5 per cent lower than they were in 1990. Within that target the government seeks to reduce CO2 emissions by 20 per cent by 2010 as part of its Climate Change Programme. Such policies place us at the leading edge of countries concerned for global climate.

Late last year most observers thought that the government had little hope of hitting the CO2 target, but on 19 January it came out fighting. It published its Green Paper on the EU emissions trading scheme with an associated draft National Allocations Plan for getting there.

The 20 per cent CO2 target has not gone away – on the contrary it is now bolstered by a shorter-term goal of a 16.3 per cent reduction by 2005-2007. The message is clear: the UK still aims to exceed its international climate change obligations.

Electricity is more than half of the UK CO2 emissions problem and last year’s energy White Paper provided the strategy to bring down such emissions. The attack is to be made on two fronts. First, there must be greater use of renewables and, second, significant improvements must be made in energy efficiency. The emissions trading scheme will be a significant extra pressure for efficiency.

One might say that in the 1990s the UK electricity industry represented a victory for the economists over the engineers. It was privatised and prices fell, to the delight of politicians, consumers and many economists. But low prices cannot alone define good energy policy. Policy-makers must grapple with the fact that low prices, and perceived low prices, act against attempts to encourage greater energy efficiency.

If the efficiency gains needed are to be achieved, then all aspects of the problem will need to be attacked. In November 2003 the Carbon Trust launched its ‘lifeblood’ campaign with a series of unpleasant advertisements showing bleeding electrical devices. The reality of the problem, however, dominated my street over Christmas. My neighbour’s suburban home lit the December night sky with a wondrous tableau of electrically illuminated snowmen, Father Christmas and cheery slogans. The cost of the electricity will have been only a minor part of his budget.

Instinctively when one thinks of energy efficiency one is drawn to measures of energy conversion efficiency (for example, replacing 100W tungsten light bulbs with 15W fluorescent bulbs). And there are gains to be made from such actions. Serious benefits, however, lie in better management of energy. There are significant savings to be made by eliminating unnecessary demands from the system and avoiding unnecessary conversion steps. For the consumer the key step must be to turn items off, or down, when not needed, for instance, by deploying automatic lighting systems that sense if nobody is around.

Avoiding energy conversion can eliminate electricity altogether, for example, the use of fibre optics and ‘light pipes’ to bring illumination directly from a roof to various internal areas. It is useful to contrast such an approach with expensive solar photovoltaic panels and power inverters on the roof of an office building to light the desk lamps of the workers below.

Another way to avoid wasteful conversions would be to wire future homes with direct current power sockets fed by a single efficient domestic transformer that senses load and responds accordingly. Increasingly the devices in our homes require only low-voltage DC power.

But the end user is not the only cause of waste. Roughly 8.3 per cent of the electricity supplied to UK consumers is lost in transmission and distribution. To ensure grid reliability generators must maintain various types of short-term reserves, including ‘spinning reserve’. These policies are established to ensure economic and reliable supply, but so far efficiency has had a minor role.

Waste exists at every level of the UK electricity system. If the country is to achieve its ambitious CO2 emissions reduction targets, dramatic progress on efficiency is needed now. Renewables will help, but by themselves they are not enough. One thing is clear: none of this will be easy or cheap.

Dr. William Nuttall is director of the MPhil in technology policy at Cambridge University.