Lighting: Saving Energy At Home
We all want to use electric light bulbs: it's the best way to illuminate our homes and places of work. However, we only need light bulbs to produce light; we do not need them to produce heat. Producing heat is a waste of electricity. If we want to make our lighting more energy efficient, we need to buy light bulbs that do not produce any heat (or, at least, not as much heat).
Lighting counts towards 30-40% of all electrical energy consumed. Using one or more of the energy-saving lighting options listed below to replace your existing lighting could cut 25% off your electricity bill, for life. If you generate part of your electricity yourself, saving energy using one of the methods above means that you will be able to use more of the power you generate for other things and buy less from the grid.
Traditional Incandescent Light Bulbs
The chances are, most of the light bulbs in your home are 'incandescent'. They work by passing a high electric current through a very thin piece of coiled wire. The wire gets so hot that it starts to glow, white hot. The result is a very hot, bright light bulb, as you will know if you've ever touched one when it is switched on! These bulbs haven't changed much in design during the last century and are very wasteful of electricity. After a few months of use, the wire (which is called a 'filament') breaks under the strain of the heat and the bulb has to be replaced. Fortunately, there are alternative types of light bulb available.
Fluorescent Light Bulbs
If you replace your incandescent light bulbs with fluorescent bulbs, you could save a LOT of energy (and, therefore, money and greenhouse gas emissions). They can last over 6 years before needing to be replaced, and each one could save you over £100 over the lifetime of the bulb in electricity savings*.
Fluorescent lights come in the form of strips or bulbs. They contain a gas mixture that becomes excited when an electric current is passed through it. The excited gasses react with the coating on the inside of the bulb to produce light. Neon lights work in a similar way, but the gasses in a Neon Light naturally give off light without the need for the coating. Fluorescent lights operate at a much cooler temperature than incandescent bulbs and are therefore much more efficient, using only a quarter of the electricity.
LED lights are perfect for replacing halogen spotlights. LED lights take advantage of the Light Emitting Diode, an electronic component usually used to show that a circuit or device is switched on (for example, the standby light on your television set is probably an LED). They work in a similar fashion to incandescent bulbs, except they do not have a filament that burns out; they have a piece of semi-conductor that emits light when a small current passes through it. They do not get very hot and therefore consume much less energy than an incandescent bulb (about 5-6 times less energy).
Natural lighting is something that many building miss out on. Larger, double or triple glazed windows can help save on energy bills by providing natural light and heat (a literal greenhouse effect). Natural light can also be concentrated and channelled through optical fibres to provide zero-energy indoor lighting, replacing light bulbs during daylight hours.
* Source: The Energy Saving Trust - www.energysavingtrust.org.uk