February 2008

Appliances &Uncategorized26 Feb 2008 09:06 pm

My article on televisions and electricity consumption is now available on the Mail & Guardian website at this link. The previous post contains all of the practical advice that a television buyer could glean from the article, but the original text does provide more context. It also includes a salient comment by Professor Ernst Uken, head of the Energy Institute at the Cape Peninsula University of Technology.

Uken says households play a larger role in the South African power crisis than their overall consumption would suggest. The morning and evening spikes in power usage are caused by the domestic sector, he says, “and spikes are the reason for the power outages. The tail is wagging the dog.”

Appliances &Uncategorized22 Feb 2008 09:14 am

Perhaps you have heard of Moore’s Law. Named after the founder of Intel, Gordon Moore, it states that computing power of integrated circuits doubles every two years. In the latest issue of the Mail & Guardian, I have introduced what shall heretofore be known as Boroughs’s Law. Named after the founder of Greenerhouse, Don Boroughs, it states that for each additional ten inches in flat-panel television screen size, its electricity consumption approximately doubles.

I discovered this law by plotting the consumption of TVs sold in South Africa on a graph, and it’s the most important thing you need to know when buying a television. Because just to look at it, you might think that a 50 inch TV—manufacturers measure these things on the diagonal in inches—would use 20 percent more electricity than a 40 inch TV. You would be wrong.

Forty-inch TVs shouldn’t use more than 250 watts. (The worst ones use more.) Fifty-inch TVs typically use 500 watts, more than six 60-watt lamps. Boroughs’s Law works all the way through the range of television sizes available in South Africa, from 20 inches to 60 inches.

This tells you that the first thing to do is when buying a television is to convince your partner—or yourself—that you can get by with a TV one size smaller than the one you have been considering. A 32-inch LCD TV, which would have been considered large not many years ago, should use a reasonable 150 watts. That’s not much more than the average large CRT TV—the kind of TV we’ve all been using for the past few decades—and even less than the least efficient CRTs. (Cathode Ray Tubes.) Sony sells a 20-inch LCD which uses an amazing 60 watts. The incredible efficiency of LCD screens at small sizes—and only at small sizes—explains why they are the greenest choice for computer screens.

Once you have decided on a size, there is still a wide range of power consumption, even within the same brand of television. Thirty-two inch TVs, for example, vary in consumption from 132 watts to 380 watts. Televisions should come with big labels stating their consumption, and one day they will. In the meantime, there are only two ways of learning the wattage of a television: through the internet or checking the label on the back of the TV. If you are researching from home, try these websites:


Once you find a TV that interests you on the web page, click on “technical specifications,” or similar wording. The wattage is usually hidden near the bottom of the list.

You should be able to find a 32-inch TV using 140 watts, a 42-inch screen using 240 watts, or a 46-inch model using 270 watts. LCD TVs tend to use less electricity than plasma TVs. If you really feel that you must have a larger TV, the only models that use acceptable amounts of power are rear-projection TVs. Experts say that their picture quality is as good as flat-panels, they cost a lot less, and the Sony models use about 200 watts, all the way up to a 60-inch screen. They are bulkier, however, and will not be available for too much longer, as they are losing the battle for market share. This may lead to close-out bargains.

If you don’t want to sift through a hundred models, I suggest starting with the Philips brand, as they tend to be more energy efficient. I would avoid LG, as they tend to be more power-hungry and they often don’t state the wattage on the label at the rear of the TV. If you like Sony, and money isn’t much of an object, the European Imaging & Sound Association gave its most recent Green Television of the Year award to the Sony KDL-40D3000. That exact model isn’t available in South Africa, but its local equivalent is the 40-inch D Series Bravia model KLV-40D300A, which uses 180 watts.

Their voting panel looks at ease of recycling and other environmental issues in addition to electricity consumption, so this should be an all-around good choice if you need a big TV.

Or of course you could just stick with your existing CRT television. I checked my 2-year-old, 29-inch Philips CRT television, and it uses 73 watts. If you use an older TV, it is doubly important that you switch it off at the box, rather than using the remote to put it into stand-by. (This also reduces the chance of damage from a lightning strike.) Almost all new flat-panel TVs use one watt or less in stand-by, but older TVs draw enough power in stand-by that in a day you may use more electricity not watching TV than you do watching it.

Global Warming &Recycling &Uncategorized19 Feb 2008 12:02 pm

Mapungubwe Gold Rhino

Any golden white elephants—or rhinos—in your house?

In recent days, the gold price is breaking record after record. Add to that the somewhat weaker rand, and your jewelry box is starting to look like, well, a gold mine.

If you decide to take some profits on a rarely worn bracelet, as I recently did, the environment will benefit even more than your bank account. In November, dozens of South African corporations released data on their greenhouse-gas emissions as part of the South African Carbon Disclosure Project. They should be commended for their effort. Knowing your emissions is a critical first step toward reducing them. Two of the companies were gold miners, and their disclosure came as a shock to me. For each ounce of gold produced by Harmony Gold Mining, 2.1 tons of carbon dioxide are released into the atmosphere. Yes, read it again, 2.1 tons of CO2 for an ounce of gold. If you don’t believe me, see here.

AngloGold Ashanti had significantly lower figures, probably because it is less dependent on deep underground mines in South Africa, but the average of the two companies still comes out at 1.14 tons per troy ounce. This is not far off from a figure I got using data for the South African gold mining industry as a whole in the year 2000, 1.3 tons of CO2 per troy ounce for electricity usage alone.

Using the 1.14 figure, by my calculations, I would have to drive my Honda Jazz from Johannesburg to Cape Town and back about three times to emit the carbon dioxide contained in a Krugerrand. (And I’m leaving aside the water pollution, local air pollution, and landscape scarring that gold mining causes.)

This might give you some pause when your anniversary next comes up, but it does make the current high gold price a perfect opportunity to recycle some gold and prevent further mining emissions. I found a medal that had no real sentimental value and my wife found a clunky bracelet that she hadn’t worn in more than 20 years. Yesterday, a gold and coin dealer paid me more than R4,000 for the two, thereby saving 783 kilograms of CO2 using to the Anglo/Harmony average. It was like buying a carbon offset, except I got paid for it. I’m considering going back with a pair of silver candlesticks.

I remember that driving all the way to Bedfordview just to sell a little gold gave me a twinge of green guilt. Not anymore. I now realize I could have driven all the way to Bulawayo.

Recycling &Uncategorized10 Feb 2008 10:38 am

Mail & Guardian collect a can
My article on Collect-a-Can is now available on the Mail & Guardian website at this link.

Recycling &Uncategorized08 Feb 2008 08:30 am

collectacanlogocrop.gif          collect a can man

Why are these men smiling? A wheelbarrow full of cans will only get them R2.86 at Collect-a-Can.

My article in the current issue of the Mail & Guardian points out that Collect-a-Can is not living up to its reputation as an energetic catalyst for recycling in South Africa. Instead of paying a premium price to the hawkers who clean up our trash looking for recyclables, Collect-a-can is paying less than the market price and profiting on the export of cans to steel mills in Pakistan.

So where does that leave the consumer who wants to do the right thing with his or her cans? One lesson I have learned is that food cans are actually somewhat more recyclable than drink cans. The food tins that make it to Collect-a-Can have their tin removed for reuse and are melted back into high-quality steel here in South Africa. Drink cans are not likely to end up as new drink cans. They meet a variety of fates, including being used to process cobalt in Botswana and going into lower-quality steels.

I know that the temptation is stronger to throw out a food tin, because of food stuck inside. I pulled one out of my kitchen bin just yesterday. Resist. All of your tins are worth recycling. Aluminium tins, including some deodorant and hair-care aerosols, are by far the most recyclable of all. I have written about this before.

I will continue to recycle drink cans as well. I would prefer “cradle-to-cradle” recycling, which means that the end product is of the same quality as the original, but this is not always possible. Converting hiqh-quality South African steel into lower-quality steel in Pakistan or even into a flux used to process cobalt in Botswana is better than wasting the resource entirely. Since global warming is indeed “global,” it doesn’t matter too much whether the energy is saved in Pakistan or Vanderbijlpark. (From the point of view of Eskom’s crisis, it does matter, but there is little you or I can do to resolve technical steelmaking issues.)

At the shops, if you must decide between disposable plastic, glass and steel packaging for beverages, there is not a strong reason to choose one over the other, so buy the one that is easiest for you to recycle. You might experiment by leaving a bag of each next to your dustbins on collection morning and see which (if any) a hawker will take. I know they will take aluminium and office paper, but in my neighbourhood, the ordinary bottles and cans are usually left alone. So I deliver them to my municipal Pikitup depot when I take grass clippings and leaves for composting. Please report back to Greenerhouse what the street collectors will take in your suburb.

Glass collection bins are becoming easier to find, thanks to The Glass Recycling Company, which has a list of bottle banks here. PET is more valuable per kilogram than any of them, though a kilogram of PET takes up a lot more space. Better by far is to find returnable glass bottles, which are available for the most popular brands from SAB Miller and Coca-Cola. And best of all, of course, is tap water.

Lighting &Uncategorized02 Feb 2008 09:40 pm

frogs on CFL

Frogs love CFLs

E TV news tonight featured a report on me and my house, looking at ways to save electricity. The tour of my house that I gave to the eTV reporter earlier in the week made me realise that I have not yet adequately described on GreenerHouse how I try to save electricity on lighting. So here is a summary of what I have done.

1. IRC Energy Saving Halogens from Osram. Fluorescent bulbs save the most electricity, but in the public rooms of the house, I have compromised by including halogen downlighters, often in tandem with fluorescents. There is a myth out there that the term “low-voltage” in low-voltage halogen lights means that they save energy. The voltage has no impact on the amount of electricity you use. You pay for watts, not volts.

That said, if you search you can find special halogen bulbs that do save electricity. They are made by Osram, and they convert some of the excess infra-red (heat) radiation back into visible light. As a result, a 35 watt IRC (Infrared Coating) halogen gives on the light of an ordinary 50 watt halogen. A 20 watt IRC is as bright as a 35 watt halogen. Most people with downlighters have far more light than they need, so they can replace their 50 watt bulbs with 20 watt energy-saving halogens. Almost all of my downlighters are using 20 watts.

These savings come at a price, however. Osram’s energy-saving halogens cost considerably more than ordinary halogens, though they do last longer, which helps compensate for the cost. They are also harder to find. Look for them in better lighting shops and large DIY centres. The bad news is that Osram has stopped importing the 20 watt versions of these bulbs; they only sell 35 watt bulbs. I’ve found a source in the U.S., but not at quantities to sell. Please call Osram at 011 207 5600, ask for sales and nag them to start importing the 20 watt ones again.

2. Compact fluorescents. So much has been written about CFLs that it’s a waste of my time and yours to tell to write at length about how much money and electricity they save. Despite knowing that they are the right bulb to buy, many people still avoid them, for some reasons that I would like to address.

Myths and Old Ideas: Flickering, Headaches, Greenlight, Start-up power.

CFLs have electronic ballasts, so they don’t flicker like old fluorescent tubes with magnetic ballasts and are unlikely to cause headaches. The colour of the light from modern fluorescents is still not perfect, but it is a far cry from the green pallor given off by old tubes. I buy good-brand (Osram, GE, etc.) warm-white bulbs and find that their glow is pleasant enough. Mixing IRC halogens with warm-white bulbs improves the colour even more. Some people avoid all fluorescents because they believe that they use so much more power when starting than incandescents that they must be left on for a long time to avoid the wasted power on re-start. This urban legend, which I believed for most of my life, is debunked here.

They don’t fit.

The newer spiral designs of CFLs take up less space than but the globes are still slightly larger than a conventional incandescent. For this reason, I avoid lampshades with the wide, flat look that became popular a few years ago. A lampshade with a little height works better. Two ceiling fixtures that I have used very successfully can be found at Radiant, the wholesaler that supplies hundreds of lighting shops in South Africa. In their catalogue under downlights>fluorescent is the BA-01 downlighter. I light a long passage in my home with four BA-01 fixtures fitted with 8 watt “triples.” These CFLs have three glass loops instead of two, so they are shorter and don’t protrude from the fixtures. My large patio is lit with two JG-56 ceiling fixtures. (Look under Ceiling Lights>Decorative Modern.) Each has three 11-watt CFLs, so I can light the whole patio for 66 watts. Most ceiling fixtures are too flat to take anything other than an energy-hogging halogen, typically using 150 watts.

I also had trouble fitting CFLs under the glass domes of three bedroom ceiling fans, so I removed the dome and replaced them with a giant 20-watt CFL globes. These are not always easy to find. I special-ordered mine from a lighting supplier. Osram calls theirs the Osram Dulux EL LL Globe.

3. Dimmers. The problem with dimmers is that people use them as an excuse to put too much light in a room. Running halogens at 50 percent power all the time because you put too many lights in your room is a bad idea. The lamps become increasingly inefficient as you reduce the power. In other words, two 50 watt halogens at half their brightness will use more watts than one 50 watt halogen at full power. Halogens also need to work from time to time at full power or their lifetime is diminished. If your halogen-lit room is too bright, first put in lower wattage lamps, and then use the dimmer to save more electricity when you have that romantic dinner.

There is a myth that fluorescent tubes cannot work on dimmers. Even most of the staff in lighting stores believe this. But I have concealed fluorescent tubes in my lounge that I work on a dimmer every day. This requires a special electronic ballast that is made for dimming. If you want to be able to dim fluorescent tubes, seek out the most intelligent looking person in a good lighting store and don’t take no for an answer.

4. Outdoor Security Lighting. I don’t have any proof, but I think that a remote sensor light that only turns on when someone walks past it offers more security than a light left on the whole night. I use them at all approaches to my house. As it turns on, dogs and householders are alerted. I do have proof that they save a tremendous amount of electricity compared to leaving lights on. Also, outdoor lighting is terrible for migrating birds. The International Dark Sky Association has many convincing arguments against what they call “light pollution.”

There will come a time when we can buy LED and Microwave lights that will use even less electricity. Neither the environment nor Eskom can afford to have you wait for that day, however. And once you’ve filled your house with all of these wonderful lights, don’t for get that the best thing to do with them, of course, is to leave them off.