Philips MASTER LEDspot R63  ©  2015 Don Boroughs

LEDs help you see double

I recently completed an energy-efficiency evaluation for a home in Northcliff. The homeowners are paying up to a few thousand rand a month on electricity and want to find ways to reduce their utility bills and their environmental impact. In coming up with a custom solution to their lighting needs, I devised a simple rule of thumb that can help any homeowner with an interest in profitable investments.

The house is largely filled with incandescent bulbs, but the couple are conscientious about switching off lights in rooms they don’t use. They spend most of their time in a family/dining/TV room, where the ceiling light fixtures are on for the duration of every evening. The two fixtures hold a total of six 60 watt incandescent floodlamps. At 360 watts for about 4 and a half hours a night, they are spending about R1,000 a year to light just that room. In most parts of South Africa with higher tariffs, it would amount to considerably more — up to R1,350.)

I presented them with a spreadsheet showing that if they could replace those wasteful incandescents with the LEDs that I found them for about R100 each, they would pay off the cost of the bulbs in just over a year and would double their money in two years. And then the proverbial light bulb lit up above my head. (An LED light bulb, of course.) What could be more appealing than a chance to double your money? So I ran more spreadsheets with the conservative assumptions that LEDs cost roughly R150 and save 49 watts each, that the homeowner pays the upper end of Johannesburg tariffs, and those rates rise by 10 percent a year. Below you will find the results showing how quickly you can double your money by investing it in switching from incandescent or halogen globes to LEDs, according to the number of hours the lights in that room are on each day:


    5 hours a day ⟶ ⟶ ⟶ Double your money in 2 years
    Just over 3 hours a day → Double your money in 3 years
    1 hour 45 minutes a day → Double your money in 5 years

If you know of any investments on the Johannesburg Stock Exchange that promise to double your money in just a few years, let me know. And these investments pay dividends to the air we breathe, the fish in the sea and the atmosphere.

LEDs are quite easy to find now when replacing halogen downlights, standard “A” globes and candle bulbs. The particular globes I was seeking for the family in Northcliff, however, were not easy to find. I needed 6 LED floodlamps in a shape known as R63. (The diameter of the bulb is 63 mm at its widest.) A couple of R63 LED globes in minor brands were available at Game and Lighting Warehouse, but I prefer to trust major brands like Osram and Philips. Finally, I found them at the Lamp House in Linbro Park for R105 each. These were warm-white, dimmable Philips MASTER LEDspot bulbs with a wide, 40 degree beam. The only downside was that they are the equivalent of a 40 watt incandescent, so if a fixture is barely bright enough for the room, it might be better to wait until the 60 watt equivalent bulbs reach our shores. My Northcliff family are satisfied with the light from their new LEDs — and glad they put their money in one of the safest investments in South Africa.