How to choose a light bulb

When choosing a light bulb, you have to take in consideration its intended use, whether it will be used in a room where brighter lighting is required (office) or where softer lighting is better, like a bathroom or bedroom.  A good way to determine the amount of incandescent watts you will need in choosing a light bulb, is to multiply the square footage of the room by 1.5. If you have a room which measures 5 x 10 ( 50 x 11.5 = 75) in footage, you will need approximately 75 watts to produce a well lit room.

A common mistake is that consumers think wattage determines the brightness of the light bulb, this is incorrect. Wattage only indicates how much energy the light bulb consumes, not how bright the light bulb is. Lumens determine how bright the light bulb will be. With bulbs being designed to consume less energy nowadays, wattage should be considered when choosing a light bulb. A standard 60-watt incandescent light bulb produces about 800 lumens of light. If you compare this to a CFL light bulb, it will also produce 800 lumens, but using less than 15 watts in the process.  When choosing a light bulb, it is much easier and efficient to compare lumens to lumens, as lumens to wattage, regardless if you are shopping for incandescent, CFL, Halogen or LEDs.

Light bulb options:

CFL (Compact fluorescent light bulbs): These light bulbs may cost more at the till, but it saves you a lot in the long run, when considering energy saving and a lower utility bill yearly. They last 7 to ten times longer than the old school incandescent light bulbs and can use up to 75% less energy. These light bulbs are great for the environment, but do have a few not so great factors. A few being the soft buzzing sound they emit,  it takes a few seconds for the light bulb to reach its full brightness, these light bulbs cannot be used in lighting systems such as dimming lights. The most effective use for light bulbs like these is in places where lights are being left on for long spaces of time, like a hallway, your outside patio at night or a baby nursery.

Halogen light bulbs:  They are quite bright as they are incandescent bulbs, but is more energy efficient than the regular incandescent bulbs. They are also more expensive than regular incandescent light bulbs and don’t last as long as the above mentioned CFL bulbs, but they are good candidates for usage in lamps where bright lighting is required.

Incandescent light bulbs: These are the most common used light bulbs in households for years. They aren’t expensive at all, but yet, we pay the price in utility bills and the environment. Even though readily still available on the market, we encourage the use of more energy saving option, like the CFL or LED when choosing a light bulb.

LEDs: The best option by far, hence Eskom offering rebates on them if you qualify. One light bulb, if used for a couple of hours a day, can easily last up to 40 years. They have a wide range of sub products to choose from, like different colours and work well with dimmer lighting. The LED lights have a tendency to be rather bright in the spot they are directed at, so many museums and art galleries choose this type of lighting on the focus of the exhibition.

When choosing a light bulb, never use wattage in a fixture higher than what it is recommended on the fixture itself. This could cause overheating and lead to electrical fires. One could spot this danger by a brownish spot on the light fixture’s insulation.  A light bulb comes in different shades, from slight blue glows to yellow to bright white glows. The reason for this is that color temperature is rated in degrees Kelvin. The lower the Kelvin number, the more yellow the glow of the bulb, higher Kelvin numbers emit a more blue glow.

When choosing light bulbs for outdoor usage, ensure and double check that it is in a fixture that is weather resistant, keeping the light bulb dry and free from water damage. Check the light bulb packages for usage indication.






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