GREENer HOUSE

Chris Yelland and the team at EE Publishers are the gurus of all things to do with electric power. So all South Africans would do well to pay attention to their analysis in this morning’s EE News: Brace yourself – the electricity price trajectory for years to come…
The article makes the point that when the National Energy Regulator of South Africa nixed Eskom’s proposed annual rate increases of up to 35 percent . . .

Many consumers breathed a sigh of relief, but a fact that received little attention at the time was the indication by NERSA that the 25% p.a. increases allowed for 2010, 2011 and 2012 would now likely continue after 2012.

The article later adds:

Irrespective of which scenario is considered, the projected electricity prices in the draft IRP 2010 show annual increases well above inflation up to 2021, and it would appear that the golden era of Eskom price increases at or below inflation will only arrive thereafter.

And concludes:

. . . take heart! Electricity prices should level off in about ten years time. Highlight 2021 in your diary as the dawn of a new era of Eskom price increases in line with inflation. Maybe…

I ran some of these numbers through a spreadsheet to see what they might mean to my electricity bill. For Eskom to reach the prices it originally envisioned before NERSA put a lid on annual increases, 25 percent price hikes will have to continue to at least 2014. Assuming that City Power of Johannesburg passes these increases on to residential users, this means that the 68 cents per kilowatt hour we pay today could leap to R1.66 in the next 3 years.

I don’t raise this issue to increase anyone’s blood pressure. What interests me is that this information completely changes any cost-benefit analysis of investments in energy efficiency at home. Back at my spreadsheets I find that  a solar hot water system that would pay for itself in 5 years at 68 cents a kilowatt hours, recoups the outlay in just 2 years at R1.66 a kilowatt hour. An efficient, variable-speed pool pump that makes sense as an investment over 7 years, suddenly makes much more sense by turning profitable in just 3 years.  LED lights that were expected to cover their costs in 6 years achieve that mark in 2 1/2 years.

I don’t think that every effort to make a greener house has to pay for itself. A little bit of financial analysis does help point out the changes that can make the greatest impact for the least expense, however. Eskom may not be doing our budgets any favours, but it sure is turning the cost-benefit analysis for eco-friendly investments green.

95 right? More likely wrong.

The conversation after Sunday lunch somehow migrated to the topic of octane in petrol. A woman was complaining that her husband makes her buy premium 95 petrol even though it costs more. The husband, who drives a Prius, was defending the extra expense on the grounds that the extra octane makes the engine run more efficiently, reducing carbon dioxide emissions.

I had never heard this before, and any idea that might reduce C0₂ emissions catches my ear. Was I unwittingly damaging the atmosphere by my frugal habit of buying the cheaper petrol? I had to look into this.

One of the best sources of information available was an Engen FAQ on octane, which confirmed, as I had suspected, that we cheapskates are right. “The great majority of vehicles inland . . .  are satisfied by 93 octane,” the website explains. “The use of octane grades higher than your vehicle actually requires will cost you more, cost the country more and have a negative environmental impact.”

The FAQ explains that this is because:

“There will be no additional benefit to driveability or performance of your vehicle if you use a higher grade than it requires. Petrol with a higher octane requires more severe refining and greater energy use in the production process. If not offset by greater fuel efficiency of the vehicle using the fuel, this extra energy use is wasted energy. This wastage results in higher emissions of greenhouse gas (carbon dioxide), which harm our environment.”

What the Engen website did not explain is the relationship between octane and altitude. Octane is purely a measure of how petrol reacts to pressure. Higher octane fuels will not ignite prematurely under higher pressure, which could cause engine knocking. But the Highveld altitude has a low ambient air pressure, which reduces the pressure inside most engines and thus reduces the need for octane. I spoke to John Fitton, an independent petroleum industry consultant, who said that most engines requiring 95 octane at the coast—as is recommended in the manual for my Honda Jazz—only need 91 octane in the Highveld.

South African regulations allow for three grades: 91, 93 and 95. At low altitude, 95 is the only grade available. Highveld petrol stations offer 93 and 95, but 91 isn’t sold at all in South Africa. Fitton told me that this is only because the petrol retailers are trying to satsify ill-informed customers. “Consumers think octane is power,” he said.

Fitton pointed out that the lower octane requirements at higher altitude do not apply to turbocharged engines and a minority of newer engines with gasoline direct injection. (These engines are sold under a variety of brand names such as Mercedes-Benz’s Charged Gasoline Injection, VW’s FSI and Ford’s EcoBoost.) Owners of these cars should obey the instructions in the car manual whether they are in Lesotho or Lambert’s Bay. For the rest, Fitton said, “There’s no advantage to using the higher octane; you’re just going to spend more money and emit more C0₂.”

The new view from my lounge

Regular GreenerHouse readers know that I believe a closed-combustion wood stove is one of the greenest ways to heat your home. (And that burning wood in an open fireplace is perhaps the worst.) Early this year, I finally decided to put my funds where my flue is. I kept quiet about this at first, because I thought I should experience a winter’s worth of cold weather before reporting on the results.

First, the numbers: I already had a fireplace with an inefficient Jetmaster in it, so rather than a stove that juts out into the room, I opted for a fireplace insert. The Danish-built Scan 3-5 insert I purchased from Cosy Heating cost a steep R27,000. There are less costly stoves and inserts out there, but these high-tech wood-burners are never cheap. Running costs are a different story. A cubic meter of wood cost me R600 and lasted the winter, though we did escape Gauteng for three of the coldest weeks. Since buying that first load of wood, however, I have suddenly become aware of all the free firewood suburban homeowners leave on the roadside. My kids tease me about this freeloading, but I’m only saving my neighbours the cost of hauling the wood to the dump. Long before the next heating season begins, I have at least a year’s worth of wood that didn’t cost a cent. Since we used our Rinnai LPG heater much less, mostly in the morning, our gas consumption fell from about 2½ 48kg bottles for a winter to less than one bottle, saving me about R2300. A rough calculation, ignoring the cost of capital, suggests that it will take me about 16 years to recoup the R27,000 outlay. If I had been relying primarily on the gas-guzzling Jetmaster to warm my lounge, I would be confident of a relatively quick payback.

But my reasons for switching to wood were more psychological than financial, and I’m happy to report that the emotional payback was instantaneous. The romance, beauty and warmth of the fire drew my family out of their rooms to congregate in the lounge. The children repeatedly asked to eat supper in front of the fire. I usually found the 15 minute task of preparing and lighting the fire to be an earthy pleasure that carried me back to my childhood. Knowing that all of these benefits were fossil-fuel free heightened my enjoyment immensely. Since the burning wood is close to carbon neutral, my reduction in LPG consumption cut my household annual carbon dioxide emissions by approximately 300 kilograms. If I had been heating with electricity the figure would be even higher.

At times I was tempted to kick myself for not installing a wood stove years ago, but one blistery burn on my hand reminded me that little children and wood burning devices require careful thought on safety issues. My burn was a result of hastily ignoring the cardinal rule to have both hands gloved when restocking the stove. A small child could be burned just by touching the glass, which reaches hundreds of degrees. Still if I had to start from scratch, I would have a wood stove and a Rinnai gas heater, using the wood stove sporadically and only when I felt comfortable about safety while our children were young and relying on it more heavily as they became old enough to understand the risks.

Even as the heat of summer approaches, I take comfort every time I walk past my woodpile, knowing that I have evenings in front of the fire to look forward to when winter returns.

Since this blog is dedicated to finding everyday solutions for environmentally-concerned South Africans, I don’t usually stray into political issues. But my comments on the new carbon tax on automobiles, which appear in the latest issue of The Star Motoring, are relevant to the decisions car buyers make. Starting in September, the government will be adding a tax to any car that emits more that 120 grams of carbon dioxide per kilometre.

At 75 rand per gram above 120 g/km, the tax can add up. So check the website of the National Association of Automobile Manufacturers of South Africa for the carbon emission of the vehicles on your list before you head to the showroom. Despite the howls of protestation from the auto industry, I found a surprising number of cars that will attract no tax. Here’s the list:

Audi A4 2.0 TDi 100kW, Citroen C1 1.0i and C3 1.6 HDi, Daihatsu Charade 1.0, Fiat 500 1.2, Ford Fiesta 1.6 DV6, Honda CR-Z  Hybrid, (as well as the anticipated hybrid Jazz), Peugeot 107 and 207 1.6 HDi, Smart fortwo, Toyota Prius (the cleanest of the lot) and the VW Golf 6 1.6 TDi, Polo 1.6 TDi, and CrossPolo 1.6 TDi. BMW’s 320d Dsl comes so close to the mark that the tax will have no noticeable impact on the sticker price.

And in case you missed the latest Star Motoring, here are my thoughts on the tax:

The “debate” over the carbon tax on new cars is hardly a debate at all. The Retail Motor Industry’s opposition to a tax based on vehicle carbon dioxide emissions receives plenty of publicity, and the government fails to rise to the defense of the new tax, due to be implemented in September.

But there are plenty of good arguments for taxing CO₂ in the car showroom that are not being heard. The decision made at the point of sale is a fateful one, and not just for the new owner of the car. Should the buyer naively choose a thirsty vehicle without calculating the lifetime fuel costs in advance—a common occurrence—the environment will lose regardless of what happens after he drives away from the dealer.

We do not live in Japan. Cars do not head for the scrapheap after 100,000 kms. They are passed down the economic ladder to poorer and poorer drivers until they literally fall apart. So if the new owner of this vehicle suddenly turns green or tires of paying dearly at the pump, he will sell it on to someone else to do the polluting for him.

Similarly, if he decides to drive less to compensate for his fuelish vehicle—the alternative suggested by the motor industry—the car will last longer. He may be delaying its ultimate output of CO₂, but if the car will last 300,000 kms and emits 200 grams of CO₂ per kilometre, it will eventually send 60 tons of carbon dioxide into the atmosphere.

If, however, the new tax prods him to save R5250 by purchasing a vehicle that emits 130 grams/km instead, the planet will be spared 21 tons of CO₂ in that single decision.

The auto retailers do have some reasonable proposals to protect the environment. They are correct that a carbon tax on fuel gives drivers of both new and used vehicles a flexible incentive to save by driving less. They argue convincingly for stricter fuel guidelines that will give South Africans access to the cleanest new engines and improve the emissions of existing cars as well.

But global warming will not be stopped by drivers cutting back on kilometres. It will not go away because our fuel is cleaner. Nor will it be fixed by a carbon tax on inefficient new cars. It will take all of these approaches in combination and many more.

Many eminent scientists believe that to keep the earth from warming into the danger zone of higher than 2 degrees above pre-industrial levels, greenhouse gases will have to cut by 80 or even 90 percent in the developed world. We don’t need to choose the single best solution among many; we need to adopt all reasonable solutions.

The carbon tax on new vehicles is not perfect. It addresses only one facet of the problem, and the tax is calculated into the sticker prices instead of staring consumers in the face. But we consider it entirely acceptable to fund the government with imperfect taxes on such virtues as saving (interest tax), earning wages (income tax) spending (VAT) and running a successful business (corporate profits tax). Compared to these, a tax on the polluting capacity of new vehicles smells like a rose.

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.