Efficiency of appliances

There is large potential for reducing the electricity consumption from appliances used in domestic or commercial buildings. If, in replacing appliances, everyone bought the most efficient available, their total electricity consumption could easily drop by more than half.

Take lighting for instance. One-fifth of all electricity used in the United States goes directly into lighting. This can easily be reduced by the wider use of compact fluorescent light bulbs which are as bright as ordinary light bulbs, but use a fifth of the electricity and last eight times as long before they have to be replaced - with significant economic savings to the user. For instance, a 20-W compact fluorescent bulb (equivalent to a 100-W ordinary incandescent light bulb) costing £3 or less will use about £20 worth of electricity over its lifetime of 12 years. To cover the same period eight ordinary bulbs would be needed costing about £4 but using £100 worth of electricity. The net saving is therefore about £80. A further large increase in the efficiency of lighting will occur when light-emitting diodes (LEDs) giving out white light become commonplace.18 The latest such device which is about 1 cm2 in size and consumes only 3 W produces the same light as a 60-W incandescent bulb.

The average daily electricity use from the appliances in a home (cooker, washing machine, dishwasher, refrigerator, freezer, TVs, lighting) for typical appliances bought in the early 1990s amounts to about 10 kWh per day. If these were replaced by the most efficient available now, electricity use would fall by about two-thirds. The extra cost of the purchase of efficient appliances would soon be recovered in the savings in running cost. Similar calculations can be carried out for other appliances.

both to the companies and its customers. Similar savings would be possible in other developed countries. Major savings at least as large in percentage terms could also be made in countries with economies in transition and in developing countries if existing plant and equipment were used more efficiently.

Further large savings can be realised when buildings are being planned and designed by the employment of integrated building design. When buildings are designed, the systems for heating, air conditioning and ventilation are commonly developed separately from the main design. The value of integrated building design is that energy-saving opportunities can be taken associated with the synergies between many aspects of the overall design including the sizing of the systems where much of the energy use occurs. Many examples exist of buildings that take advantage of the many ways of increasing energy efficiency including integrated building design, that reduce energy use by 50% or more and that are often more acceptable and user-friendly than buildings designed in more traditional ways.20 Some recent examples demonstrate the possibility of more radical building designs that aim at Zero Emission

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