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.

I keep track of my fuel economy with every fill-up. It’s a little obsessive, I know, but I’ve learned quite a lot from seeing the differences in economy between cars, drivers, seasons, tyres, etc. There is good research to show that when people are aware of consumption, they tend to reduce it. It’s also good to know whether the fuel economy gauge in your car is accurate. In my experience, the gauges always make your fuel consumption look better than it really is.

I’ve made the process very simple for myself by creating an Excel spreadsheet that instantly calculates kilometres per litre and litres per 100 kilometres, with a running average for the last ten fill-ups. Now I’m making it simple for you, too, with a downloadable blank spreadsheet that has all of the formulas to make those calculations. All you have to do is reset your trip odometer at each fill-up, record the number of kilometres on the till slip—which already has the litres printed on it—and enter those two numbers on the spreadsheet.

To have your own copy of the spreadsheet, click on this link:

FuelEconomy

You should then be offered the option of opening it directly in Excel or saving it. Either option works, but if you choose to open it directly and then wish to save it—using Save As—you must be very careful to save it in the folder where you keep spreadsheets. It will not automatically opt for the My Documents folder.

After using it, if you’re not pleased with the fuel economy you see, try my 10 Unconventional Tips for Saving Petrol.

Note: FuelEconomy.xls was scanned with a fully updated version of Norton AntiVirus 2009 immediately before it was uploaded to GreenerHouse. No viruses or other security risks were found. That said, GreenerHouse promises not to take credit for your improved fuel economy if you promise not to make GreenerHouse responsible for any troubles with your computer or your spouse arising from the use of this file.

For years, I have tracked my household electricity consumption, sometimes on a daily basis. Knowing my daily kilowatt hours has taught me much about the impact heaters, oven, clothes drier, and especially my solar hot water system, and how it is affected by usage, weather and seasons. It has helped me set targets for conserving electricity and to monitor my progress. And it has helped me to catch problems quickly. If I see a sudden leap in my kilowatt hours, I know I will find that the pool pump has been left on override, or the geyser is drawing electricity when it shouldn’t.

There are fancy devices out there—not available in South Africa—to bring all of this information into your home. One day I would like to own one. But I do this all with my ordinary municipal meter and a simple, but effective Excel spreadsheet. I have now created a downloadable blank version to make tracking your electricity consumption incredibly easy, even if you know nothing about Microsoft Excel. All you do is fill in the date and your current meter reading. (The final digit on the meter is normally a decimal, which I ignore or round off.) The spreadsheet will calculate the average daily consumption since you last took your reading. To try it out, click here:

ElectricityMeterReadingsBlank

Your computer should ask whether you wish to open it directly in Excel or save it. Either option works, but if you choose to open it directly and later save it—using Save As—be very careful to save it in the folder where you keep spreadsheets. It will not automatically opt for the My Documents folder.

I hope it helps you save electricity, or at least gives you some ammunition when fighting the municipality over outlandish readings.

Note: ElectricityMeterReadingsBlank.xls was scanned with a fully updated version of Norton AntiVirus 2009 immediately before it was uploaded to GreenerHouse. No viruses or other security risks were found. Still, GreenerHouse can take no responsibility for any consequences arising from its use.

Swimming season’s here; start shoveling coal

I didn’t mean to wait until spring had fully sprung before restarting my pool pump, but I forgot to turn it on in August. Even though September is well under way, the water is still not green after leaving the pool pump off for 110 days. Compared to running the 0.75 kilowatt pump for 3 hours a day—as I previously did in the winters—I have saved myself nearly 250 kilowatt hours and spared the atmosphere a similar number of kilograms of carbon dioxide. Financially, I saved about R140 off my municipal bill. Compared to the conventional wisdom of running the pump 12 hours a day, I saved about R550 and kept a few bags of coal out of the pool. My only expense was R20 worth of algaecide.

I don’t like the idea of using algaecide, or any other pool chemical, for that matter. I know far too little about what happens to these chemicals when I backwash the pool. But the likelihood that the algaecide is still very toxic after more than 3 months in the pool seems rather slim.

So can I declare the experiment a success? Not quite. I should have anticipated that the pool pump was not happy to start after being left idle for so long. I had to physically get it turning with my hands—while the electricity was off—before it would move on its own. In the process I may have strained the capacitor. A new capacitor costs less than a hundred rand, but I hardly want to put my pump through such agony at the end of each winter. Next winter, I will set the timer to run the pump for a half hour each day. (Not during Eskom’s peak morning and evening hours.) I’m sure that a couple of hours exercise once a week would also keep the pump lively, if I trusted myself to remember.

Will this work on your pool? I certainly wouldn’t try it without a pool cover. And my pool cover is particularly suited to protecting the water from sunlight. After years of frustration with the limited durability of ordinary bubble pool covers, I bought a heavy duty bubble cover of the kind used on indoor public pools. It doesn’t let through light, so it adds no heat to the pool. That doesn’t matter to me since I have solar panels to warm the pool. And after more than 4 years, it’s still strong.

I would be very interested to hear from others about their experiments with near-zero pumping.

The July issue of Real Simple magazine is now off the newsstand. So in case you missed it, I am reprinting my article about green renovations. The editors asked that the information be presented  as a series of questions for the various contractors that might work on a home renovation. I couldn’t really do justice to any of the subjects covered in that format and the space allowed, so I will try to expand upon some of them in future posts.

Crumbling house prices and economic jitters have convinced many homeowners that it’s safer to adapt what they have to what they need, rather than jump into a shaky housing market. But can a renovation help your house adapt to the planet as well?

Throwing a few photovoltaic solar panels on the roof won’t make your home green. And environmentally sensitive architects have moved beyond the singular obsession with energy efficiency. The catchphrase of green building in the 21^st century is “embodied energy.” How much fossil fuel went into the bricks, cement, steel and glass that make up your house? What quantity of greenhouse gases is your home responsible for even before you switch on the first light? For some houses, the embodied energy of day one will exceed the sum of a few decades worth of electricity and gas bills.

Building in harmony with nature means working with the local climate, local suppliers, and even local soil. There is no one-size-fits-all solution. Instead of waiting for easy answers, start with the right questions. And if a contractor stares blankly at the ceiling in response to your queries, you may want to look for someone with greener credentials.

Architect:

How earthy can our house be? Green architects agree that adobe, cob and rammed earth are wall materials of first choice for low embodied energy. An architect who has worked with them will know whether they suit your project. The biggest concern: banks will not approve a bond for new structures supported by such raw materials. A home renovation, however, may be able to get financing.

Can we aggressively pursue passive solar? The right combination of windows, walls and floors can supply most of your heating needs in sunny South Africa. But a large roof overhang is vital to keep the high summer sun out. If your architect cannot calculate the ideal overhang based on your latitude, orientation, roof pitch and height, find another architect.

Can we build around a wood stove? If you have a local source of sustainable wood, such as suburban tree fellers, a closed-combustion wood stove is the greenest way to heat. But with all of your warmth concentrated in one spot, careful designing is needed to help the heat reach colder parts of the house. Keeping the stove central to an open plan but away from any double-volume ceilings is a good start.

How can our home use nature’s air conditioning? Your architect should know how to take advantage of prevailing winds. Low windows on the cooler, south side of the house can draw breezes to force out summer heat from high windows on the north side. Drain the pool of heat on your ceiling with small, high windows that you can leave open all night without worrying about cats or cat-burglars. Transom windows aid the flow between rooms. Trees or shutters can shield western surfaces from the afternoon sun. Don’t let some sweet-talking salesman convince you into electric air-conditioning until you’ve given nature a chance.

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It’s not coal in the pool today

Those who have read my previous post on pools know that I don’t fall for the usual advice that pool pumps should run 12 hours a day, year-round. Still, reducing my pumping schedule to just 3 hours a day in the winter just wansn’t radical enough for me. No one is swimming. The pool cover doesn’t budge. The water’s cold enough to give algae the shivers. I’m turning the pump off.

Yesterday, I backwashed, threw in 3 ½ cups of chlorine and a litre of Pace algaecide into my 30,000 litre pool and ran the pump overnight. Today, I turned it off. I intend to start it again sometime in August. I will report back on the results then.

Before                                         After

I have always considered our refrigeration set-up to be rather modest. No bar fridge. No chest freezer. No massive side-by-side fridge-freezer. (That’s the least efficient configuration; freezer on top is the most efficient.) We manage to keep five people fed with a single, rather small, 300 litre LG refrigerator-freezer that receives an A rating for energy efficiency from the European Union.

So I was a little bit disappointed when I used my Watts Up meter to measure the actual consumption of this appliance recently and found that it was chewing through 2.5 kilowatt hours a day, about 10 percent of my household consumption. When I researched the issue on the internet, I saw numerous references to dirty coils lowering efficiency, so I pulled the fridge out of its slot in the kitchen. I feel a little embarrassed to publish the photograph above, because it is a stiff indictment of our housekeeping, but you have to see it to realize that when I say years of dust had clogged the vents, I really mean it.

After a quick vacuuming, I was eager to test whether the improved air-flow to the coils would lower my electricity consumption. I measured at night so that the comparisons would not be thrown off by family members opening the doors during the day. Consumption fell by more than 17 percent after the fridge was freed of its dust blanket. Since the condenser works much harder during the day than at night, the true improvement may be much larger. I have now set an annual memo on my Outlook calendar to remind me to keep the vents clean and my refrigerator green.

Watts up? Pro meter

I have a new toy. It’s called a Watts up?, and it will measure the watts used by anything with a plug, up to about 2200 watts. It will calculate watt hours, as well, which is essential for appliances that cycle on and off. Watt hours are what you and I and the environment pay for. Quite simply, a 1 watt device running for an hour has used 1 watt hour. The electricity meters on houses measure kilowatt hour, or 1,000 watt hours, and that’s what we pay for in our electricity bills. For each kilowatt hour we use, Eskom sends about 1 kg of carbon dioxide into the atmosphere.

I’ve been playing with my toy for about a week, and I now have a good idea of how much electricity is used by what.

Here, in no particular order, are some of my findings.

•Washing Machine: 214 watt hours for full load. My mother-in-law always believed that clothes fare better in a cold wash, so we have always set our washing machine on cold. (Who am I to argue with my mother-in-law?) The washing machine is rated at 2360 watts, so it might burn out my Watts Up meter if I tested a hot load, but my calculations are that if we washed in warm or hot water, that number would rise by 10 times.

•Philips 29-inch CRT Television. 73 watts on, zero on stand-by. You won’t find a big flat-screen LCD or plasma TV that uses anywhere near that little.

•DSTV Personal Video Recorder PVR: 29 watts. This is worse than it looks. Forget the fact that the PVR tells you it’s “going to sleep,” or “coming out of sleep.” It uses 29 watts all day every day, three-quarters of a kilowatt hour per day, 270 kWh per year. What irritates me is that the designers could have engineered a PVR that powers down the hard drive when it’s not needed, as my laptop does every time I stop using it for several minutes.

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