DISTRIBUTING AND CONSERVING ENERGY: ALTERNATIVES
How is energy distributed?
The main discussions of future energy systems focus on the generation and distribution of electricity. At present, 93% of electricity worldwide is supplied through centralised generation, as in Britain, where it is distributed through the National Grid1. The advantage of this is that if output fails or lowers at one power station, for whatever reason, the deficit can be supplied from other power stations in the grid.
However, it is estimated that nearly two-thirds of the original input energy is wasted, with the consumer receiving barely more than a third of the original input. Further wastage occurs in both domestic and commercial use through inefficient use. See diagram2. As a result, 20% of the UK's carbon dioxide emissions result from energy wasted by centralised fossil fuel generation3.
What alternative systems are there for distributing energy?
Alternative systems for distributing energy are closely tied up with efficient energy use (including strategies for reducing consumption of energy) and with developing alternative sources of energy. Poster 23 illustrates some ways in which energy might be generated locally (Decentralised Energy), while still being connected to local and national networks. These include photovoltaic cells, wind turbines, biogas, cogeneration and trigeneration plants and gasification plants. An important feature is the way in which new homes are built.
How might homes be built to save energy?
A key feature in conserving energy in any home, old or new, is insulation. It is possible to build new homes with such effective insulation that minimal heating is required most of the time and to insulate older homes to a much more efficient standard than is generally the case at present. The energy that is needed for heat and light could be generated on site, with householders not needing to rely on the National Grid at all. Article 2 illustrates ways in which energy could be generated at home (microgeneration)
Are these systems currently feasible?
40% of national electricity demand in the Netherlands is currently met by Decentralised Energy (DE) (compared with 5% in the UK).
77% of Woking Borough Council's carbon dioxide emissions have been slashed over 15 years by setting up DE networks and instigating energy efficiency measures4.
As reported in Article 2, an estimated 300,000 homes in the US are now independent of utility companies (i.e. generate their own light and heat)
The same article quotes research by the Energy Savings Trust suggesting that home generation of power could potentially provide 30-40% of the UK's electricity needs by 2050.
What can be done in the meantime to conserve energy?
Whatever means of producing energy are adopted in the future, reducing energy consumption will remain key to the efficient use of energy and the conservation of natural resources. Below are a number of ways in which energy can be conserved in the home. Factsheet 6, Poster 3 and Lesson Plan 3 explore this further.
insulating roof, cavity walls, hot water cylinder
using low energy light bulbs
buying energy efficient appliances
replacing an old central heating boiler with a condensing boiler
turning off lights and heating when rooms are not in use
reducing purchase of non-essential items
turning off computers, television, DVD when not in use
page last updated 31 May 2006