Low Energy House - Low Energy Bulbs - Compact Fluorescent Lamps

Artificial lighting accounts for over 15 per cent of electricity use in most houses. Money can be saved by replacing the traditional, general lighting service bulbs, with the latest low energy bulbs ( compact fluorescent lamps)

General Lighting Service Bulbs (GLS)

The traditional GLS light bulbs are of the incandescent type. When an electric current passes through the filament the wire is heated causing it to emit light. As a result, only 10 per cent of the electrical energy is converted to light, the other 90 per cent converts to heat energy and is wasted.

Low Energy Bulbs - Compact Fluorescent Lamps (CFLs)

The new energy efficient bulbs are also known as compact fluorescent lamps. They work on the same principle as fluorescent strip lights but on a smaller scale. They provide as much light as standard incandescent bulbs but use a quarter of the energy. They also convert most of the electrical energy to light and not heat.

Low Energy Bulb Replacement

Low energy bulbs can be used to replace traditional light bulbs at any time. They are most cost effective when fitted in rooms that are most used i.e. living room, kitchen and hall. Low Energy Bulbs are produced in a variety of sizes and shapes and are available with either bayonet or screw fittings.

Traditional Bulbs 25 watts 40 watts 60 watts 75 watts 100 watts 120 watts

Compact Fluorescent Lamps 5 watts 9 watts 11 watts 15 watts 20 watts 23 watts

Equivalent Wattage Table

Like standard light bulbs, low energy bulbs are rated in watts but because they use less energy they operate at lower wattage. The table shows the approximate wattage equivalents.

Electronic Ballasts for Low Energy Bulbs

Good quality low energy bulbs are equipped with a ‘high frequency electronic ballast’ which controls the electric current passing through the fluorescent discharge tubes. The electronic ballasts are enclosed in the same casing as the lamp. They provide instant illumination, reduce flicker and enable lamps to achieve full brilliance very quickly.

Re-Usable Electronic Ballasts for Low Energy Bulbs

It is now possible to buy electronic ballasts that are detachable from the bulb section. These are known as modular units and are initially more expensive than the one-piece bulbs. The bulb part can be discarded at the end of its useful life and the ballast retained for re-use. This greatly reduces the long term cost as it reduces waste.

Low Energy Labelling on Low Energy Bulbs

The energy labelling now used for white goods i.e. refrigerators, washing machines etc. is also available on low energy bulb packaging. The labelling shows the energy efficiency rated from A to G (A - rating being the most efficient and G - rating being the least efficient). The packaging also displays the power consumption in watts, the light output in lumens and the life of the low energy bulb in hours.

Cost of Low Energy Bulbs

As low energy bulbs have become more widespread the unit cost has fallen. Some supermarkets now have them on special offer or sell them on a loss leader basis.

Schemes and Promotions for Low Energy Bulbs

Large numbers of low energy bulbs are given away through the Standards of Performance Programme which requires that energy suppliers meet energy saving requirements through their customers. Contact your electricity and gas suppliers to see if they are offering free or discounted bulbs.