by : Neil Ebsworth

Ask most people the question 'Who invented the light bulbs?' and you are likely to get the reply 'Thomas Edison'. Whilst the question could be deemed to be a little ambiguous, you may get a tick or a cross depending on the questioners point of view.

It was Humphrey Davy, the English chemist who first attached wires to a battery and passed an electric current through a piece of carbon to create the first arc lamp back in 1809. The list of contributors between this humble beginning and Thomas Edisons' filament light bulb in 1879 is quite a long one and any one of them could have the title bestowed on them.

Warren De la Rue in 1820 used platinum as the source of his arc. He did use an evacuated tube so this could be said to be the first attempt at a light bulb. The cost of the platinum however was too expensive to make this idea feasible for widespread use. In fact it was not until 1875 that Henry Woodward and Matthew Evans patented the first light bulb and it was this patent bought by Edison and modified that led to him creating a filament bulb that worked for 40 hours.

It was not long after the Edison light bulb that fluorescent lamps were created. In 1890, Peter Cooper Hewitt created the first lamps that used gas as opposed to a filament to pass electric current through to create illumination. It was not until 1973 that Ed Hammer and General Electric came up with the design for the compact fluorescent lamp, or light bulb as we know it today. At the time, it was deemed too expensive to set up production of the low wattage bulbs and the design plans were shelved. Later the design plans leaked out and were eventually copied by others.

The energy saving capacity of the low power light bulbs is due to their use of gas instead filament as the conduit for the electrical charge. Fluorescent lights in industrial settings such as factories and offices have benefited from these savings for years. The percentage of electrical usage in the average household in the United States amounts to 9% of the total usage by each household. The use of low power bulbs could reduce this by 7% to just 2%. Not only would this save on efficiency, the amount of reduced carbon emissions would have an extremely positive effect on global warming.

There are some negatives with low power light bulbs. They contain a very small amount of mercury which has an effect on disposal when they are used up. The environmental impact of breakages also poses a small hazard as broken bulbs release small amounts of mercury vapor. None of these are major problems and the benefits of this type of lighting far out way the risks.

Another set of lights that follow the same compact design are the metal halide lamps. Metal Halide lamps are part of the HID group of lamps or high intensity discharge family. Mainly used in industrial settings these lamps use a high pressure mixture of argon, mercury and different combinations of metal halides to create a variety of specialist lighting effects. Most commonly, the metal halide lamps were used in outdoor lighting settings, street lighting and parking lots. Their high intensity effect being best suited for pointed, directional lighting.

In conclusion, light fixtures have come a long way since the days of Davy and Edison and the future is destined to be one of changing technologies as we strive to become more efficient in our use of electrical power. The use in cartoons of a light bulb above the head to simulate the breaking of a new idea is ironic as we look to the future for ways to conserve our energy resources.