GREENer HOUSE

His                                          Hers

I received an email today from someone asking whether Jetmasters use a lot of gas. It’s a question that I answered best a few years ago when I wrote about heaters for Fairlady magazine. So I’m reprinting that article below.  Other GreenerHouse posts on heating can be found here and here.

Warm House, Cool Planet

The battle of the sexes erupted in our lounge one recent winter when our creaky Westpoint oil heater finally conked out. To replace it, my wife demanded something that flickered yellow, glowed orange and suggested romance. I insisted on something calculated to maximize efficiency, easy on my green conscience and not too hard on my wallet over the long-term, either. In the end, there was only one way to keep the peace: His and hers heaters.

Chilly consumers today are faced with a wider range of home heating options than ever before. You can plug in convection heaters, oil-filled radiators, or fan heaters. You can light anthracite in a fireplace, a convector, or an airtight stove. You can install electric heating wires underfloor, undertile or undercarpet. Gas heaters may be radiant or convective, flued or unflued, rollabout, built-in or freestanding, and any combination of the above. To add to the confusion, what looks cheap today may cost more down the line. And more importantly, what appears clean may force the environment to pay a price for generations to come.

South Africans have made electricity their first choice for home heating, encouraged by some of the cheapest kilowatts in the world. But Eskom derives 88 percent of its power from the dirtiest of fossil fuels: coal. Think of the electric main arriving at your house as a little pipeline of coal slurry. For every 100 rand on your electric bill, more than a quarter tonne of carbon dioxide has been pumped into the atmosphere on your behalf. The Australian Consumers’ Association has calculated that in equally coal-dependent Sydney, where winters are a little cooler than Cape Town’s, but considerably warmer than Johannesburg’s, warming a house with electric heaters can contribute 3.4 tonnes of CO2 toward global warming each year, far more than any other energy source they investigated.

In the resulting global greenhouse, the last of Mt. Kilimanjaro’s glacial ice will melt in 2015; South Africa’s drought-plagued maize crop will fall by a fifth in the next 50 years; and rising temperatures will trigger massive extinctions of sensitive fynbos flowers. It may be too late to stop some of these catastrophic projections from becoming reality, but I would rather not have them on my conscience. I moved down the list to other heating options.

Ironically, burning anthracite coal at home can produce far less carbon dioxide than heating with electricity. It depends on how you burn it, however. Throw the nuggets into a hole-in-the-wall fireplace, and up to 90 percent of your heat and coal-budget goes up the chimney. This black option makes electricity look positively green. Modern, tapered fireplaces and convectors improve the heat output, but the cleanest, most efficient option is an airtight heating stove. These pricey heaters—nearly R8 000 for Franco Belge’s popular Belfort stove—combine high-tech inner construction with an old-fashioned, cast-iron exterior to convert 65 to 85 percent of coal energy into heat for the room. In contrast, three-quarters of the coal energy that goes into electricity is lost in generation and transmission.

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Our morning got off to a curious start, to my mind. When my 17-year-old finally awoke, my wife asked if she wanted to come along for a jog.

“No,” she replied, “I have an extra maths lesson in one hour.”

“That’s fine,” I said, to my wife. “You run, and I will walk her to maths.” (1.8 km away)

“Walk?,” exclaimed my wife, “She doesn’t have time for that; she has tons of homework.”

If the humour of this conversation does not immediately occur to you, perhaps you should exercise your mind. Our culture has compartmentalized each aspect of our lives so completely that exercise is a specialized activity done purely for its own sake and worth the time it requires. Traveling to school, work, shops, friends or errands is a separate activity, to be done as quickly as possible, by car. Using a slower mode of transport is a waste of time, even if it involves exercise. But my calculations show that traveling more slowly actually saves me time, in two ways.

I jog for exercise and pleasure and cycle to get around and also for pleasure. It horrifies me to see people who will ride a bicycle all the way to the Magaliesburg on a Saturday morning for fun, get home, shower and hop in the car to get to the post office. I’ve seen this happen.

My longest regular ride is to a weekly voice lesson. It’s a 7.5 km trip by car that takes 15 minutes, or a cycle of anywhere from 25 to 35 minutes. On the morning of my voice lesson, I skip my usual one-hour jog, saving the same time that it will take me to cycle in both directions. Jogging and then driving would together take an hour and a half. Cycling takes one hour. 60 + (15 x 2) – (30 x 2) = 30. I save a half hour.

That’s not all I save. I don’t keep track, but I figure that sometime this year I will have made my hundredth cycle to my lesson. 100 x (7.5 x 2) = 1,500. That’s 1,500 kms of driving I have saved—farther than Johannesburg to Cape Town—and 150 litres of petrol worth well over a thousand rand. The environment has been spared more than 350 kg of carbon dioxide.

Let’s exercise our maths some more. A health study following more than 5,000 people over 40 years concluded that exercise equivalent to walking for 30 minutes a day for five days a week adds 1.3 to 1.5 years to your life.  Do those regular walks for 30 years, and you will spend 234,000 minutes walking, (30 x 5 x 52 x 30 = 234,000) but will have added 735,840 minutes to your life. (1.4 x 60 x 24 x 365 = 735,840.) So the averages tell me that the 20 minute stroll to her maths lesson added perhaps an hour to my daughter’s life. 735,840 ÷ 234,000 x 20 = 62.89. And, she later reported, “It was a pleasant walk.”

1 + 1 = 2.

After two weeks of municipal strikes, the wheelie bins lining the roads are starting to bulge . . . and smell. There’s one plus to this, however. Since the surplus of refuse is literally lifting the lids of the bins, I’ve been able to get an easy look at what people are throwing away. To a large extent, they are throwing away greens. And there’s nothing green about that.

One of the most dangerous myths about the environment is that it is better to send something biodegradable to a landfill than something that will last a hundred years, like a plastic bottle. Quite frankly, that’s a load of garbage.

The last thing you want to happen in a landfill is biodegradation. Deep in a landfill, in the absence of oxygen, bacteria break down plant material into methane. This gas is 21 times more potent as a greenhouse gas than carbon dioxide. If garden waste is composted or left to decompose in the garden, it will give off carbon dioxide, but only as much as it absorbed when it was growing. So sending plants to the landfill is 21 times worse for the atmosphere than composting them.

Grass clippings are the worst, since they decompose much faster than, say, twigs. It is impossible to precisely calculate these things, because of the many variables in landfills, but a reasonable estimate based on a thorough scientific report, is that 1 kg of garden waste in a landfill will give off 77 grams of methane. This means that a full, standard black refuse bag (750mm x 950mm) containing  14 kg of grass clippings will give off as much greenhouse gasses as burning 9.5 litres of petrol by driving nearly 100 kilometres. Recycling the equivalent quantity of plastic—the same bag filled with 3 kgs of empty PET plastic bottles—would save less than a sixth as much greenhouse gases as composting that bag full of grass.

Our lawn space is considerably smaller than many suburban gardens. But my gardener says that in the summer, he mows about two bags worth of clippings twice a week. So in some months, our grass clippings would be causing as much damage to the atmosphere as the electricity consumed by our house, if we were throwing these clippings out with the garbage.

But we don’t. I don’t have much energy for composting, so just a fraction of the clippings go into a somewhat neglected compost pile, which nonetheless manages to produce some good compost in time. The rest is stored in reusable large woven polypropylene bags until we have a carload. Then I haul them a couple of kilometres to the nearest Pikitup garden refuse transfer site, so the municipality can compost for me. It’s a small inconvenience to keep my grass truly green.

Polar Bears Don't Like AC

The December issue of Red: the Green Magazine is out in the Cape, and it features an article I wrote about alternatives to air conditioning, especially evaporative cooling.  Here’s what it has to say:

Craig Bransgrove has been installing air conditioning in Cape Town homes and offices for the last six years. So it may seem surprising that when he recently installed a cooling system for his own home, he did not choose traditional air conditioning at all. Bransgrove’s Blouberg home uses an evaporative cooling system that takes advantage of the same effect that makes a wet swimming costume feel so chilly on a windy day. “I looked at all the options,” says Bransgrove. “It’s a lot healthier and it’s cost effective.”

Evaporative cooling is gaining popularity as environmentally conscious South Africans increasingly look for ways to keep cool without resorting to air conditioning. In the driest parts of the country, the systems are actually more common than refrigeration air conditioning in residential installments. “I don’t think there’s a household in Upington that doesn’t have evap cooling in it,” says Philip Coreejes, owner of Hi Power Electric.

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Since the issue of Maverick containing my Solar Photovoltaics vs. Diesel Generators article is off the newsstands, I can now publish the article in full on Greenerhouse. Enjoy:

Bringing Back the Light:

Diesel vs. Photovoltaic

It began with an email. My brother-in-law asked me, the family’s resident green guru, to weigh up the relative merits of diesel generators vs. solar power.

Load shedding is clearly driving him to distraction. Computers are crashing in his home office, and he has scrambled to reschedule meetings of 30 and 40 people to stay out of the dark. He wants to know that the power will be there where he needs it, when he needs it. “I’m looking for a complete solution, and I don’t want hassles,” he told me, admitting that he was close to choosing the diesel route.

But he also knows that his green credentials need some buffing since he traded in his Honda Jazz for a Land Rover Discovery last year. Is solar electricity an affordable alternative?

Until the beginning of this year, the answer to his question would have been simple: In South Africa, solar cells may be virtuous, but they don’t pay for themselves. (Solar hot-water panels do pay for themselves, but you can’t run your PC on hot water.) Even the national sales manager for Sanyo photovoltaic panels in South Africa, Win Kurzyca, says, “it doesn’t pay me to put 10 of these on my roof—even at staff price—instead of paying 32 cents a kilowatt hour for electricity.”

But suddenly everything has changed. In fact, the question has changed. My swaer is not asking whether photovoltaic panels pay for themselves; he wants to know whether solar electricity is competitive with diesel-generated electricity.

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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.

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.

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.

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.