GREENer HOUSE

Those Frogs Still Prefer CFLs

Yesterday in my daughter’s science class, the subject of energy efficiency came up, and another girl in the class mentioned that she had heard that our house was full of energy-saving devices. So my daughter had to explain what we were doing at home to save electricity. One boy asked if manufacturing those compact fluorescent light bulbs doesn’t use more electricity than making a common incandescent globe.

She didn’t know the answer. And neither did I. But I was glad that the younger generation thinks about the carbon footprint of the products we buy, and I thought it deserved a little research. After much digging, I came up with some information from Osram about the electricity that goes into making their bulbs.

Osram says that they need 3.36 kilowatt hours to produce each 15 watt CFL. This is about two-and-a-half times the amount of electricity required to make the equivalent 75 watt incandescent globe, 1.29 kilowatt hours. An incandescent bulb is a simpler product, after all. So the advantage goes to the incandescent on day one.

It loses the advantage quickly, however. If you use the two bulbs for four hours a day, by the 9^th day, the incandescent has used so much more electricity that it has lost its advantage. By the end of a year, my very rudimentary life-cycle analysis shows the CFL winning the race by 25.26 kWh to a whopping 110.79 kWh for the incandescent.

Even if you were burning these bulbs in Iceland, using carbon-dioxide-free geothermal and hydroelectric power, the CFL would be more environmentally friendly because it lasts longer and so one CFL is the equivalent of several incandescents.

If, like Noah, you know that the world is going to be swallowed up in a flood in a few days, an incandescent bulb is the green choice. If you think the flood might take a few more years as the Greenland ice cap melts, you should buy CFLs.

This week, my favourite little Rinnai gas heater stopped working when load shedding began on a cold night. It may use gas, but it also has an electric fan so it isn’t Eskom-proof. I’ve been looking at alternatives.

Last year at about this time, I wrote an overview of home heating options. In it, I ranked an open fireplace heated by gas 8th out of 11 options, well worse than average. This is because gas may burn cleanly, but any open fireplace loses most of its heat up the flue.

I failed to mention then that I own a Jetmaster open gas fireplace. In the past, I only used it a few times a year for ambience when we had guests, but I’ll have to use it a lot more during load shedding this winter since it’s my only heater that runs without electricity. That’s a problem, because LPG has risen in price from R367 for a 48 kg bottle when I installed the Jetmaster in 2001 to R820 now. And according to my own ranking, I’ll be using one of the least environmentally friendly options around.

When I first installed the Jetmaster, I briefly considered a wood stove, but I knew that wood burning was a source of carcinogenic particulates, and I didn’t see how wood made sense in a semi-arid country with so few trees.

I’ve learned two important things since then. First, I got a quick lesson in urban forestry a few years ago when I had to remove a giant dying oak from my garden. It broke my heart to see tons of potential firewood being carted away by a tree-feller who told me he was taking it to the dump. (The trunk and limbs were too large for me to split.) The logs would ultimately decompose, releasing greenhouse gasses without benefiting anyone. I called around and learned that some other tree-fellers cut and split the wood they retrieve to sell for firewood. In the future, I would only use a tree-feller who recycled this way.

Johannesburg is sometimes called the world’s largest urban forest. I suspect that this is hyperbole that could not be proven, but the fact is that the city creates enough firewood to heat many more local homes than it currently does. (Though not all of the homes, of course.)

The second education I received was when I began researching the latest wood stoves and fireplace inserts. They aren’t just better than open fireplaces, they are unrecognizably better. An open wood fireplace loses 90 percent or more of its heat up the chimney and releases about 50 grams of particulates per hour. Anyone who has read what I have writing about diesel emissions in the Mail & Guardian and on this website knows that particulates are a serious health risk.

But modern stoves typically emit 2 to 4 grams of particulates per hour, and some are closer to 1, that’s just 2% of the particulate pollution from a wood-burning open fireplace. And about a quarter of what a typical diesel car might produce. In addition, they retain 75 percent or more of the energy in the wood to heat the room, losing just a fraction to the flue. A free-standing stove unfortunately doesn’t suit my lounge, but the fireplace inserts are only a few percentage points less efficient and just as clean.

Perhaps most important, burning wood is widely considered to be almost carbon neutral, because a decaying dead tree would release carbon dioxide anyway, while a new tree growing in the place of the old one absorbs the greenhouse gas. Firewood from the urban forest is even closer to carbon neutral than most because it was going to be cut anyway and involves minimal transport.

Only two fireplace inserts fit my opening, but they seem like good units. I’m seriously considering the Scan DSA 3-5, which rates at 76 percent efficiency. I haven’t yet found particulate emissions data for this fireplace, but it seems similar to the DSA 4 which emits a very low 1.1 grams of particulates per hour. If I could choose among a wider range of wood stoves, I would look for one with the Swan eco-label. Among the brands in South Africa, Scan, Morsø, and Jötul all have stoves that meet the wide variety of environment criteria to earn the Swan logo. A list of Swan stoves can be found here.
These advanced, closed-combustion stoves are not cheap. Expect to pay at least R10 000, and up to R40 000 for a top-of-the-line wood burning stove. But the wood is cheap. Malcolm Sims of Cosy Heating has done calculations suggesting that gas now sells for R1.23 per kilowatt hour of energy, whereas wood is about 30 cents per kwh if burned in a 75 percent efficient stove-cheaper than electricity. (Cosy Heating sells both gas and wood heaters.) Comparing my inefficient Jetmaster with the Scan fireplace, I could heat with wood for one-tenth the price, though the Jetmaster offers greater control in adjusting the flame, which would mitigate that somewhat.

Sadly, Cosy Heating says that my Scan fireplace is out of stock because of the load-shedding rush. So for the next seven weeks we’ll be huddling next to the open gas fireplace when the lights go out, and thinking about how warm that chimney must be.

I just received a comment to a year-old post about compact fluorescent lamps. The reader raises concerns about mercury in CFLs. I replied to him at length with my own comment, but the information is too important to leave it buried there.

The issue of mercury in CFLs keeps rearing its head. I once read a long article in the Star that left the reader with the impression that CFLs’ negatives may outweigh their positives.

This is simply not true. If you read what the independent experts have to say, it is clear that compact fluorescents reduce the amount of mercury in the environment in the long run. One thorough article on the subject notes that:

CFLs represent between 0.006 and 0.04 percent of U.S. anthropogenic [mercury] emissions

It concludes:

CFLs prevent the emissions of substantial quantities of mercury, greenhouse gases and other pollutants; they reduce consumer energy bills; and they last far longer than incandescent alternatives. They are currently the environmentally preferable product despite their mercury content – whether they are recycled or not.

Two other web pages worth reading on the subject can be found at the Natural Resources Defense Council and Popular Mechanics.

The reason CFLs can contribute to mercury emission reductions despite containing mercury is that coal-burning power plants are the world’s largest contributor to mercury emissions. In the U.S., they are responsible for about a third of the mercury released. Since coal accounts for less than half of U.S. electricity generation and about 90 percent of South Africa’s electricity generation, it’s safe to say that more than half of all mercury released in South Africa comes from Eskom. Cut your electricity consumption and you reduce mercury pollution.

Aside from the broader environmental issue, some people are concerned about exposing their families to a source of dangerous mercury in their homes. John Balbus, M.D., the Chief Health Officer at Environmental Defense, writes

The exposure from breaking a compact fluorescent bulb is in about the same range as the exposure from eating a can or two of tuna fish.

Still, if a bulb breaks in your home, it’s worth following a few precautions such as using disposable paper towels to wipe up—not a vacuum cleaner—and washing your hands when you are finished. For more details, you can read the instructions suggested by the U.S. Environmental Protection Agency.

I don’t want to go too far in minimizing the dangers of mercury. It is a serious poison, and we should all try to reduce our contribution to mercury pollution in any way we can. Batteries are a very large source of mercury, so you should only buy watch batteries and alkaline batteries that are mercury free. (Recyclable batteries are even better, of course.)

In buying CFLs, the best recommendation is to stick with major international brands such as Osram, GE and Philips. They have to comply with EU standards that allow no more than 5 mg of mercury in a globe. Osram CFLs have 3.5 mg according to their technical marketing manager in South Africa, Wally Wilmans. Cheaper brands may have more.

There is no way to recycle CFLs in South Africa currently, but Eskom has a working group tasked with this issue. CFLs last so long that before the bulb you buy today burns out, even Eskom may have come up with a plan.

A warm, green towel, served medium-well

A friend of mine stopped by yesterday on his way home from shopping for a heated towel rail. He had been fretting for years at his wife’s extravagant use of the tumble dryer simply to warm and dry a single towel before bathing. He worries that tumble dryers use vast amounts of electricity. I used to have a similar affliction, until my tumble dryer broke down last year. I simply didn’t bother to repair it, and I have been a happy man ever since.

The towel rail my friend wants to buy, he told me, uses about as much electricity as a single light bulb, or 100 watts. Though my friend is a former maths teacher, I wasn’t convinced that he had done his calculations.

Heated towel rails are designed to run constantly; they generally don’t come with timers or thermostats, other than a safety shut-off to prevent overheating. If he runs this towel rail constantly for a year it will consume 876 kilowatt hours of electricity and add nearly a ton of carbon dioxide to the atmosphere. In my house, that would mean a 10 percent jump in total consumption most months. And at the rates just proposed by the Johannesburg municipality for the coming year, the towel rail would increase his annual electricity bill more than R350. If rates triple over the next several years, as predicted by some experts, the annual cost would approach R1000.

Tumble dryers use roughly 2000 to 3000 watts. That’s terrible. But presuming that his wife doesn’t leave the tumble dryer running all day to keep her towel warm and dry, it might use less electricity than the towel rail. Run a 2500 watt tumble drier for a 30 minutes a day and it will use less than half the electricity—and contribute half the carbon dioxide—of  a round-the-clock towel rail.

That’s still not good for the environment, however. The almost-environmentally-friendly solution is to have an electrician install the towel rail with a switch and a timer and then use it a few hours a day in the winter and turn it off entirely in the summer. The hundreds of rand you will save each year will easily pay for the timer. The problem with this solution is that it contributes to load-shedding because it will add to your electricity consumption at the exact morning and evening peak hours when Eskom has no spare capacity.

If you really can’t see a way to keep your spouse happy without warm towels—and I am very conscious that sometimes we must compromise to avoid marital misery—I suggest trying the microwave oven. WARNING: YOU CAN BURN YOUR SKIN OR EVEN START A FIRE IF YOU HEAT A TOWEL IN THE MICROWAVE FOR TOO LONG. I would not even attempt this in a microwave without a digital timer, and children should not be allowed to try this unsupervised. For my 750-watt microwave oven, 30 seconds warms a small towel nicely and 45 seconds heats a large bath-sheet towel to perfection. Thirty seconds at 750 watts is a mere 2 percent of the electricity used by a 100-watt towel rail in 3 hours. If you don’t have a doting lover on hand to run the warm towel from the kitchen, warm two towels for 30 seconds each and wrap one inside the other to keep warm while you bath or shower. Just because I’m opposed to global warming doesn’t mean that I don’t support wet-body warming.

GreenerHouse has made the short list for the 2008 South African Blog Awards in the category of Green Blogs. If you think this is the best environmental blog in South Africa, and believe that more South Africans should be exposed to the ideas and information found on Greenerhouse, click on the button to the right. A nomination will bring this site to the attention of many people who might not otherwise hear about it. There’s no money in it for me, but the posts I write for Greenerhouse are only worth the time I spend on them if lots of South Africans get to read them.

The voting process is simpler than the rather tricky nominating process, I promise. Voting concludes on the 19th of March.

One is greener than the other

This week I took delivery of a 48 kg cylinder of liquid propane gas. This may seem odd, because I only use gas for heating in the winter. (I wrote about this here.)

But it was all part of a plan. Because burning LPG purchased in the summer may be about the only way to use a fossil fuel at virtually no cost to the environment. That’s right, no net carbon dioxide emissions, sulfur dioxide or any other nasties will be released into the atmosphere as I stay warm burning this gas in the coming winter.

The logic is this: LPG is a byproduct of the refining process. Wherever petrol is made from oil, gas or coal in South Africa, some LPG is produced. As a friend a Sasol first told me, in the summer, when LPG demand is down, these plants run out of storage capacity for LPG and frequently flare it. So if I work on the assumption that my new bottle of gas would have been flared into the atmosphere anyway, I can burn it with a clean conscience.

I planned ahead for this moment back in August, when one gas bottle was depleted. I always have one spare 48 kg cylinder on hand, and replace an empty as soon as I switch over. But two weeks into August I did some quick calculations and figured there was no way my new bottle would run out before warm weather arrived.

Of course, if South Africa had a rational, competitive market, LPG prices would come down in the summer, everyone would have a financial incentive to plan ahead and buy gas in the summer, and flaring of LPG would come to an end. But anyone who buys bread or has a bank account in this country knows that we do not have a rational, competitive market.

So should I buy more LPG bottles to get me through the winter? I don’t know. I worry that South Africa could run into a gas-cylinder shortage this winter. So many people are switching to gas for cooking because they no longer trust Eskom. I will try to investigate the gas-bottle supply situation before winter arrives. If it looks good, I will buy an extra bottle and let you know.

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.”

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:

www.philips.co.za
www.sony.co.za
www.samsung.co.za

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.

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.

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