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    Solar cooking works, from sunny Brazil to Seattle

    Northeast Seattleites are cooking up momentum for a simple, cost-efficient technology that stops deforestation, greenhouse emissions, and lethal cookfire smoke. Why doesn't it get more respect elsewhere?

    The folding CooKit, developed in 1994.

    The folding CooKit, developed in 1994. Solar Cookers International

    Seattle workshop goers flash their new clamshell cookers.

    Seattle workshop goers flash their new clamshell cookers. Leo Brodie/NE Sustainable Seattle

    From the oven...

    From the oven... Eric Scigliano

    ...to the table.

    ...to the table. Eric Scigliano

    Ashton Vital explains alternative box-cooker designs.

    Ashton Vital explains alternative box-cooker designs. Eric Scigliano

    Northwest Public Radio’s enterprising Tom Banse was working on a collaborative project on wood smoke in this region when he came upon a much bigger story — a global one. The effects of wood stoves here are just a puff of, well, smoke compared to the ills suffered, and perpetrated, by up to 3 billion people around the world who depend on biomass — wood, charcoal, dung, and the like — to cook their food. Smoky, inefficient cookfires such as the classic “three rock” arrangement cause tens of millions of respiratory ailments and some 1.5 million deaths each year, more than malaria.

    The soot they produce is a potent greenhouse agent in itself, and if it falls on snow — say, Himalayan glaciers or arctic icepack — it reduces the snow’s albedo, making it absorb more heat and melt faster, a proverbial feedback loop. And gathering or buying firewood consumes an enormous share of many power people’s time and income. It’s a main cause of deforestation, degrading habitat, triggering erosion, and further contributing to global warming — another feedback loop.

    Banse found that a growing movement is attempting to remedy this situation by replacing those dirty cookfires with clean, efficient stoves that consume less fuel and produce much, much less smoke and illness. And that the Northwest is home to a “burgeoning cluster of lifesaving stove designers” — at least four of them, anyway.

    The clean-stove movement has indeed come into its own recently, with an outpouring of media and official attention. Last year, the United Nations Foundation, together with the U.S., German, and Norwegian governments and others, launched the most ambitious initiative yet, the Global Alliance for Clean Cookstoves; Secretary of State Hillary Clinton, who got attuned to the issue when she traveled as First Lady and saw poor people staggering under heaps of firewood, was a main instigator. It proposes not merely to send clean stoves around the world, but to insinuate them so thoroughly into local economies and customs that people from Kampala to Kathmandu will keep manufacturing and buying them on their own.

    But valuable and impressive as all this is, it’s not the full story, nor a perfect solution to the cookfire conundrum. A fire-free alternative, variously described as a “solar cooker” or “solar oven,” can not only reduce but eliminate toxic smoke, costly fuel, and their attendant ills. Solar cookers can be assembled from everyday, even scrap, materials for less than the target cost ($10) of clean-burning stoves.

    Clean stoves stand to dirty cookfires as Priuses and Fiestas do to smoky old gas guzzlers. But solar cookers are like bicycles — except they don’t entail anything like the exertion and loss of capacity and functionality that come with switching from a car to a bike.

    Solar cookers are an idea that’s been hiding in plain sight for a very long time — and Seattle is a hotbed for them too. In 2009 the Financial Times awarded its $75,000 FT Climate Challenge award for “the most innovative and scalable solution to the effects of climate change” to the Kyoto Box, a cheap cooker made out of an insulated cardboard box lined with tinfoil and black paint, with a clear acrylic cover to catch the heat (a beneficial application of the greenhouse effect). It was a ringing endorsement of the idea of solar cooking, and of the appeal of super-cheap, simple design; I felt the same way the first time I saw a similar box cooker in action, in Brazil a few months before the FT contest. But it also seems a gesture of astonishing naiveté by a sophisticated newspaper, a bit of clever brand appropriation, and an indication of the widespread ignorance of solar cooking.

    According to various promoters and practitioners of such cookery, the idea goes back to the 18th or 19th century. Box cookers like the Kyoto have been around for decades. “We laughed at that [prize choice],” says AmyJo Mattheis, executive director of the California-based nonprofit Solar Cookers International. “His cooker doesn’t even work!” Indeed, a promotional video of the original cardboard model suggests it wouldn’t: It had heat-absorbent black where it should have had reflective foil. A new model, apparently developed with that $75,000 prize, is made of sturdier polystyrene, with reflective lining.

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    Posted Fri, Dec 23, 1:26 p.m. Inappropriate

    America's Test Kitchen tested solar cookers and, in addition to other information, had this to say, "A solar cooker works like a one-way lobster trap. It lets UV light rays in and then converts them to longer infrared light rays that can't escape. Infrared radiation has the right energy to make the water, fat, and protein molecules in food vibrate vigorously and heat up.

    Practically, this means that successful cooking requires a clear sky, with the sun at least 45 degrees or more above the horizon for a significant amount of time (depending on what you're cooking, from two to eight hours)."


    Posted Fri, Dec 23, 1:44 p.m. Inappropriate

    These people have completely lost their minds.


    Posted Fri, Dec 23, 2:45 p.m. Inappropriate

    In a sunny place like Kenya it sounds like another good tool in the cooking toolbox. Smoking meat does help preserve it, which is one side effect of that style of cooking. But not having to gather wood for every meal is a huge time benefit.


    Posted Fri, Dec 30, 10:29 p.m. Inappropriate

    My solar cooker made from two large computer boxes, foil, a black sheet metal tray, and a glass lid works beautifully in Seattle 8 months of the year, when the sun is higher in the sky, cooking chicken, cake, or vegetables in about twice the time it takes in a conventional oven.

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