Energy Efficiency in brief
From Electrical Installation Guide
The aim of this chapter is to facilitate communication between the designers of electrical installations and the energy consumers who use them. Consumers frequently require advice on how best to reduce consumption and the amount they spend on energy.
While there are a number of factors influencing attitudes and opinions towards energy efficiency, particularly the increasing cost of energy and a growing awareness of our responsibilities towards the environment, legislation probably has the greatest impact on changing behaviour and practices. Various governments across the world are setting themselves energy saving targets and passing regulations to ensure these are met. Reducing greenhouse gas emissions is a global target set at the Kyoto Earth Summit in 1997 and was finally ratified by 169 countries in December 2006.
Under the Kyoto Protocol industrialised countries have agreed to reduce their collective emissions of greenhouse gases by 5.2% compared to the year 1990 between 2008 and 2012 (this represents a 29% reduction in terms of the emissions levels expected for 2012 prior to the Protocol). One of Europe’s targets is a 20% reduction in for CO2 by 2020. Given that 27% of CO2 emissions originate from transport, 16% from residential buildings, 8% from the service sector and 49% from industry proper, up to 50% of emissions can be attributed to electricity consumption associated with residential and commercial buildings. Moreover, as the use of domestic appliances and other equipment such as ventilation and air conditioning systems increases, electricity consumption is rising at a faster rate than other forms of energy.
Against this background, the following conditions will have to be satisfied in order to achieve a 20% reduction in consumption by 2020:
- All new buildings constructed must consume 50% less energy.
- 1 in 10 existing buildings must reduce consumption by 30% each year.
As far as most countries are concerned, it is clear that 80% of the buildings which will be standing in 2020 have already been constructed. The refurbishment of existing building stock and improving energy management is vital in meeting emission reduction targets. Given that in the western world, most buildings have already undergone thermal performance upgrades such as cavity wall insulation, loft insulation and double-glazing, the only potential for further savings lies in reducing the amount of energy consumed. Action to improve the thermal and energy performance of existing buildings will almost certainly become compulsory in order to meet the targets that have been set out.
Technology exists to help promote energy efficiency on many levels, from reducing electricity consumption to managing other energy sources more efficiently. Ambitious regulatory measures may be required to ensure these technologies are adopted quickly enough to achieve the 2020 targets.