March 2015


Hot Water &Solar27 Mar 2015 02:35 pm

Solar Hot Water Panels

If you are considering whether to install a solar water heater, you might want to move fast. Eskom’s rebate programme has been extended to cover solar systems installed by the end of April 2015 as long as applications are submitted by the end of May. The rebates can reduce the up-front costs of a solar water heater by up to R11,000.

This isn’t necessarily the end of solar rebates. A plan was in place to shift the responsibility for the rebates from Eskom to the Department of Energy. The extension is a stopgap measure because it appeared that the DOE was not ready to launch its rebates, and the prospect of halting incentives at a time when the grid needs all the help it can get was exactly the wrong message to be sending. The DOE has not made public all of the details of its rebate programme, but has warned that it will place a heavy emphasis on requirements for South African manufacturing content. If you can afford to install now, at least the rules are public and the rebates well-established. Better the devil you know . . .

In this era of load-shedding, there is an extra consideration to take into account when deciding on a solar system. The most efficient solar water heaters use a circulation pump between the panels and tanks, but when the electricity is off, not only does the water stop heating, but the panels can overheat. So opt for either a thermosiphon system, which needs no pump, or a pumped system that is powered by solar cells. Some hot water panels are even sold with a miniature photovoltaic panel built in to run the pump.

To help you get started, read the Guide to Solar Hot Water that I wrote for the My Green Home website.

Finally, Eskom has extended the rebate but not their solar hotline. Direct any questions to the ordinary customer service line 08600 ESKOM.

Lighting13 Mar 2015 08:34 am

candle LEDs and incandescent candle bulbs in chandelier

A candle in the wind

Four years ago, I set out on a journey to replace all of the incandescent lights in my home with modern LEDs. The final stumbling block in this quest was a candelabra in my dining room, pictured above. Candle-shape bulbs with narrow screw bases, known as “E14” bulbs, were a great source of frustration for me. Well after LED equivalents of 60 watt and even 100 watt standard-shaped bulbs became available, I couldn’t find dimmable, bright, LED replacements for these 40 watt candle globes.

My wait is over. Last week I bought three Osram Superstar Classic B40 Advanced Frosted candle bulbs at my local Lighting Warehouse for R90 each. They use 6 watts instead of 40, so the three-globe candelabra has dropped from 120 to 18 watts. Since we use the dining room lights a few hours a day, I calculate that they will pay for themselves in less than two years. They come with a four-year guarantee and a 20 year-estimated lifetime, so my investment is safe.

You can judge the quality of the light for yourself in the picture above. I left the image’s colour balance at daylight, which makes incandescent and warm-white LEDs seem a little more orange than they actually appear when your eyes adjust to them. The bulb in the upper right is the new Osram LED. The other two are my old incandescents. In this fixture, the LEDs actually light the dining room table more brightly than the incandescents did. This is in part because they cast their light away from the base. The effect might be slightly less bright if the globes screwed into the chandelier base-down, shining up to the ceiling. I find the colour of the light adequate, so overall it has been an improvement in lighting a slightly dim room.

The only noticeable disadvantage has been that on our old rotary-dial dimmer, the bulbs only seem to work at two light levels, not a continuous range. In time I will replace the dimmer with an electronic dimmer recommended for LEDs. In the meantime, I am already satisfied with this bright purchase and happy to know that my last incandescent globes are now just candles in the bin.

Global Warming04 Mar 2015 07:40 pm

Why should you take steps to reduce your tiny impact on this great big world? I heard a convincing argument in a documentary about air pollution that has taken China by storm. Chai Jing has an uncanny ability to approach environmental issues with both her heart and her head. At the end of Under the Dome she observes how she was affected after getting involved in the installation of a filter to reduce the particulate emissions of a restaurant near her home in Beijing:

“I suddenly felt like my feet hit the ground. It’s a difficult feeling to describe—you know full well that in the grand scheme of things, this is actually a small impact. But knowing that when one person is able to make a small contribution, they are able to actually make things better, their heart feels grounded. In the war between human beings and air pollution, this is how history will be made: When millions of everyday people, stand up one day and say: “No. I’m not satisfied. I don’t want to wait. I will not sit back. I will stand up and do something. Right now, right here, right in this moment, in this life.”