GREENer HOUSE

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.

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.

Call me petty, but when I received a gorgeous shirt as a gift recently, I was a little disappointed because two Jeep tags were sewn onto the front of the shirt. (Green tags nogal!)

Chrysler consistently ranks at or near the bottom of fleet fuel economy rankings in the United States, and Jeeps are the thirstist vehicles in the Chrysler stable. Some Jeeps are rated at more than 21 liters per 100 kilometres. (4.7 kms/l or 11 miles/gallon.) They definitely have not earned their green tags.

I’d rather not walk around in a shirt that adds any cachet to the Jeep brand, but I didn’t want to waste a beautiful shirt. So I solved this problem with the help of a stitch-ripper, a handy tool that should be a part of any sewing kit. Without the green tags, my shirt is so much greener.

The picture that I meant to take of Mandla

These are sad times in South Africa. And though I mostly feel quite distant from the terrible violence against our African neighbours, I have been touched by the tragedy in one, odd way.

For the past two years, a man name Mandla has rung my bell every Monday morning to see if I have any recyclables for him. I first saw him digging through garbage in my neighbourhood during one of my jogs. He was collecting white office paper, so I told him to stop by my house, since I always separate the good white stuff, which fetches a higher price. Ever since, he has made a weekly stop here. And as prices have risen for other commodities, I have given him cartloads of plastic bottles and cans in addition to paper.

I had just decided that it was time to write about Mandla on GreenerHouse. I liked the topic, because I believe that developing this kind of relationship creates meaning out of recycling, spares the collector the indignity and effort of digging through rubbish, and could save homeowners trips to the recycling depot. I had even decided that I would call the post “Meet Mandla.” I was going to take his picture and place it on the website.

It was going to be a good week for Mandla, because I had worked on the cleanup crew for my daughter’s matric dance and had rescued bins full of PET plastic bottles, aluminium cans and steel (tin) cans. I had them waiting at the gate for him. When Mandla didn’t show up last Monday, I didn’t think much of it. But now he hasn’t rung my bell for two weeks, so I know that last week was not a good week for Mandla. We had never discussed his origin; we mostly talked about the prices of various recyclable commodities. But it now seems clear that he was a Zimbabwean. In my experience, most of the hawkers who collect recyclables on foot are from other African nations.

I hope that Mandla is safe, wherever he is, and that someone is giving him lots of white paper to sell.

The latest issue of Maverick magazine, which is arriving on newsstands this week, includes an article I wrote comparing diesel generators with solar photovoltaic panels. The point is that solar cells are normally considered pricey, with little hope of paying for themselves in the near term and maybe not even in the long run. Load shedding changed all that, however, because many South Africans are now shelling out tens and even hundreds of thousands of dollars for diesel generators to make themselves Eskom-proof. In my article I compare what happens if that money is instead put into generating solar electricity on the roof. I use actual quotes for systems for one house and then run the numbers to see how the two options compare over time.

When this issue of Maverick comes off the newsstand, I will post the article in-full on GreenerHouse. In the meantime, I will share a few insights from my reporting here in the next few days.

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.