GREENer HOUSE

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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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.

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.

It’s the gift-giving season, and I see shoppers loading their trolleys with enormous boxes of biscuits. They will give most of these to people who work for them, I would guess. I’m sure the biscuits will be appreciated, but consider topping up that biscuit assortment with a gift that will keep giving for years to come. If someone you know has an electricity bill that eats a significant portion of their budget, consider giving them compact fluorescent globes.

My housekeeper returns to her newly electrified home in the North-West province during the holidays. About a year ago, when she was complaining about that her pre-paid meter there was running down too quickly every time she bought more electricity, I asked how many light fixtures she had in her home. The answer was seven, all of them using 60 watts or more. Since she didn’t have a refrigerator or geyser, these were probably the bulk of her electricity consumption. So last Christmas, I gave her 7 compact fluorescent globes that use just 11 watts each. She claims they made an instant improvement in her electricity expenditures.

Sadly, the very people who can benefit most from such an environmentally friendly technology are often the people whose budgets prevent them from paying more today to save energy in the future. That’s why compact fluorescent bulbs make a gift that is, well, brilliant.