Lighting20 Oct 2015 05:36 pm

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.

Vehicles28 Sep 2015 09:43 am


The emerging scandal at Volkswagen and Audi is raising the question of whether “clean diesel” is an oxymoron. I have shone the spotlight on this question before, and the answer for South Africa is: “Yes.” Certainly for city drivers, “clean diesel” is a contradiction in terms. You can read my article for the Mail & Guardian on this topic here.

The South African authorities have launched an investigation into whether VW’s rigged engine software was used to circumvent South African standards and the carbon tax on vehicle sales. Regardless of those results, all diesel vehicles pollute more in South Africa than in the US or Europe. Our standard diesel fuel has 10 times the sulfur found in European diesel and 33 times more sulfur than in American diesel. Paying more for low-sulfur diesel just adds to one problem while partially solving another; though engine emissions are better, 10ppm and 50 ppm fuels have a much higher coal content, contributing to higher emissions at Sasol’s refineries. You can find advice on choosing the fuel and engine suited to your driving here.

Global Warming &Hot Water &Solar10 Sep 2015 12:44 pm

Solar Hot Water Panels

The Highveld winter drought broke this past weekend with a two-day deluge. The soil needed the rain, but when you ordinarily heat your water with just the sun, it’s painful to switch the power on for the geysers. I cheered myself up with the thought that I could check how much electricity I would be using without my solar hot water system.

My home’s consumption for this sunless Saturday and Sunday averaged 30.5 kilowatt hours per day. In comparison, on the four previous weekends I was using 12 kWh/day. Assuming that hot water accounts for the difference, the sun ordinarily saves me 18.5 kWh/day, cutting my electricity bill by more than half. (I monitor my consumption using a customised spreadsheet you can download here.)

This is very close to the 19 kWh in savings I calculated in a different test here. My solar system is large — with 3 flat panels, 1 evacuated-tube panel and 600 litres of storage — and the rest of the home is very efficient, so I couldn’t promise such dramatic results on every house. But this gloomy weekend tells me that solar is saving me at least R9,000 a year, not to mention keeping 5 tons of carbon dioxide out of the atmosphere.

That’s a sunny thought no matter what the weather.

Appliances27 Aug 2015 10:28 am


The Game advertising insert that arrived in my Star newspaper this week shows nine refrigerators that seem to have earned green ribbons for energy efficiency, seven As and two B. Sounds great? If it were your child’s school report, you would be delighted. But here’s the frightening truth:

Every one of those refrigerators is so inefficient that it would be illegal to sell anywhere in Europe.

Energy labels can be useful, but you have to know how to read them. In the two decades since the EU began requiring labels, appliance makers have made such strides in efficiency that the regulators had to add A+, A++ and even A+++. Then in 2012 they banned the sale of fridges rated A or below. Today, As and Bs are old, inefficient technology, the kind of outdated goods manufacturers like to dump in Africa.

If you look around, however, all of the major brands do sell A+ and better fridges in South Africa. Only the EU label shows grades above A. The less common South African energy label stops at A. (The EU label has the blue EU flag in the top left corner; the local label has a star in the colours of the SA flag in the bottom right corner.) If a fridge carries no label, ask the salesperson to find one.

Efficient fridges might cost more, but bear in mind that over the lifetime of the appliance, you will likely pay Eskom more to keep that fridge cold than you paid the store to buy it. Typically fridges use about R1,000 to R4,000 in electricity per year, depending on your tariff, fridge size and efficiency.

Even more important than the letter grade is the kWh/year number on the EU label. Use that to compare fridges, since a smaller A+ fridge could use less power than a larger A++ one. Here’s a handy rule of thumb: Multiply the annual consumption by R40. This is approximately how much you will spend on electricity to run the fridge for the next 12 years. So a fridge that uses 300 kWh per year will cost you R12,000 in electricity. (My rule of thumb is based on an average of Johannesburg and Cape Town tariffs, rising 10 percent each year.)

For more detail on reading appliance labels, including Energy Star, South African and EU labels, see the My Green Home guide to appliance labels

Global Warming05 Aug 2015 11:20 am


Follow the trend

With the blizzard of climate-change data and research constantly swirling around, it’s easy to become disoriented. As my op-ed column in today’s Business Report points out, Keith Bryer became seriously muddled by a single data point in his July 29 opinion column. If anyone tells you that the planet is not warming because they read in Business Report that Arctic ice in increasing, show them the chart above.

As Bryer correctly pointed out, research from the European Cryosat satellite shows that the volume of ice in the Arctic increased from 2010, the year that the satellite was launched — which I have noted with a green circle on the chart — until 2013 — noted with a red circle. Bryer got lost in the blizzard when he leapt to the conclusion that this single data point from a three-year time span somehow debunks decades of science on global climate change.

As the chart shows, Arctic ice is highly variable from year to year, including a recent, three-year growth spurt, evident from the steep upward line between the two circles. But the long-term trend is clear. Anyone looking at this chart as a whole, instead of just the years 2010 to 2013, can see very clearly that the Arctic ice sheet is indeed melting. (The chart uses data from the National Snow and Ice Data Center that show the extent of Arctic sea ice, not its volume; no data on volume existed before Cryosat. But volume and area are related, and the 2010-2013 uptick is also evident in this measurement.)

In a coincidence, Cryosat was launched just after the end of an El Niño cycle that exacerbated ice loss. Then the first two years of Cryosat data collection coinciding with La Niña, which is associated with ice accumulation. So nothing about the short-term increase overturns the existing consensus.

Bryer reveals his ignorance of basic climate science by writing: “Instead of shrinking, raising sea levels, flooding coastal cities, and reversing the Gulf Stream, the Arctic ice cap has grown.” But climate scientists don’t claim that sea levels rise when sea ice melts. Bryer does not seem to understand that basic science rules out a connection between sea ice melting and sea levels.

Anyone who has watched the ice melt in their drink on a hot day knows that the level of the drink does not rise as the ice melts. Since water expands when it freezes and contracts when it melts, and since most of the ice is below the surface level, melting ice does not affect the level of your drink or the sea. Sea levels are rising by about 3 mm a year because ice on land is melting and flowing into the sea — especially mountain glaciers and the ice cap on Greenland — and because warming water expands. Those are the real threats to coastal cities.

Yes, the volume of Arctic ice grew from 2010 to 2013. Rational minds will take that as an interesting data point, not an excuse for a meltdown in logic.

Heating and Cooling21 Jul 2015 04:45 pm


I have a new toy: the Lasergrip 1080 infrared thermometer. It can measure the temperature of anything you point it at, with incredible accuracy. This winter it’s teaching me all kinds of things about the temperatures of the walls, ceiling, windows and floors of my house.

The most interesting insight is the strong evidence it has provided of the effectiveness of the draught stoppers beneath my doors. Take a look at the two photos above, taken at 7:30 this morning. The floor next to the door with no draught stopper—I removed it before I went to bed for this experiment—is more than 3 degrees Celsius colder than the floor protected from the cold air blowing under the door. Three degrees is a big difference when looking at indoor comfort.

I put that draught stopper back on right away.

Recycling14 Jul 2015 04:11 pm


My poisonous pile

My office is piling up with the victims of loadshedding: failed gate-motor and alarm batteries that were never designed to be fully depleted so frequently. When I complained to a salesman that my latest gate-motor battery had lasted only 7 months, he suggested that I be grateful; some of his customers were replacing their batteries every month.

These 12 volt, 7 amp batteries are made with poisonous lead, just like car batteries. They should be kept out of the landfill and sent for recycling. Besides, the lead has real value, especially since lead is one of the few metals that South Africa has to import. But since I was uncertain where to take them, I let these heavy, black bricks accumulate over the past few years until I had a stack of eight. The time had come to learn the best locations for lead-acid battery recycling. Actually, they were easy to find, and some even pay for used batteries.

Pick n Pay stores commonly have recycling bins at the entrance, including one for batteries. I phoned Uniross, which handles the batteries collected in these bins and learned that ordinary alkaline cells are not recyclable, but can be left in the bins for safe disposal. Small lead acid batteries like mine will be recycled. For more information on other battery types, click here.

Automotive suppliers that sell car batteries are legally required to charge a deposit on the batteries they sell and pay a deposit on the car batteries they receive. Alas, the two local branches I phoned of Battery Centre and Midas would not offer to pay for my lead-acid batteries, but they would take them off my hands. The staff who answered the phone gave me pause with their comments: “I’ll help you get rid of them,” and “They get disposed of safely.” But since these suppliers are regularly shipping car batteries for recycling, I have a fairly high level of confidence that smaller lead-acid batteries would also end up in the right place.

First National Battery has a battery recycling plant in Benoni. If you drop off at the facility, they will pay R4/kg for any lead-acid battery. My eight batteries weigh about 17kg, so they would be worth R68. Unfortunately, I live too far from Benoni to justify the time and emissions of traveling that far. For more information call 0800 333 462.

Scrap metal dealers pay even better prices. I spoke with Maningi Scrap Metals in Marlboro, Johannesburg, and their price for lead-acid batteries is R7 a kilogram. One comfort in selling the batteries rather than dropping them off is that the buyer has a financial incentive to make sure they are actually recycled.

But for the best balance between confidence and convenience, I’m dropping my batteries off next time I shop at Pick n Pay.

Appliances &Heating and Cooling07 Jul 2015 03:39 pm

Rinnai gas heater with thermostat set on high ©  2015 Don Boroughs

H is for ‘Hopelessly confused’

You like to cook your egg on a medium stove heat, but to get the pan warmed up you first set the electric hob to high, right?

You arrive at a Kruger Park rondavel on a sweltering day and turn the temperature control knob on the air conditioner thermostat as far as it will go to cool down the room more quickly, right?


You use thermostats every day. Do you understand how they work?

A just-released study of American homeowners reported here found many misuse their heating and cooling thermostats. A third of them seem to not understand how thermostats work at all.

Central heating and air conditioning are much less common in South Africa, but thermostats still govern our stoves, ovens, geysers, portable heaters, and room air conditioners. Use them incorrectly and you could be wasting energy.

I see the confusion in my own home. My Rinnai gas heater has two heating levels—high and low—and a thermostat with temperature settings from 16 to 26. The H setting above 26 means it is kept on high heat even if the room gets hotter than 26 degrees. Since no one really wants to be that hot, I should never find it turned up to H, but that’s frequently where I find it set.

The culprit who set it on high could have chosen 21 instead, for example, and as long as the room was colder than 21 degrees, the thermostat would have kept the burner on high heat, only switching down when the temperature reached 21 degrees.

The gremlins in my house and many other people and confused by the myth that a high setting on a heater, stove or air conditioners will somehow make the appliance work faster. Not so. The element in an electric stove or heater and the compressor on an air conditioner can only be on or off. A low setting on the stove allows your soup to simmer because the thermostat switches it on briefly and repeatedly.

Why does this matter? Because if you walk away or fall asleep with the stove on high and the air conditioner on max, you will waste electricity, burn your pan and shiver all night. Always set a thermostat to the final temperature you would like, then let it do the work of switching on and off. That’s what it’s made to do.

Global Warming19 Jun 2015 03:31 pm


The first five months of this year have been significantly hotter than any previous year on record, according to all three of the main agencies that monitor global temperatures. Bloomberg’s article on this news includes an amazing—and frightening—animated graphic that makes the historical changes in climate clearer than anything I have seen before. The image above is just a screenshot; click on this link to the article in order to see the graphic in action as it speeds from a cool 1880 to sizzling 2015 in 29 seconds.

Pool01 Jun 2015 03:12 pm

Pool full of Coal

Winter is here, so as usual I’m reducing the hours my pool pump runs, to 1 hour a day. This time, however, I also made a change to ease the pressure on the Eskom grid that leads to load shedding. I set the pump to run after midnight, the one time of day when Eskom has adequate power. Since my pump only uses 175 watts, it’s a small contribution, but every bit helps. I couldn’t do this if I had to worry that noise from the pump would disturb the sleep of my neighbours. Fortunately, my variable-speed pool pump is whisper-quiet, so that’s not a concern.

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