A great series on the recycling industry in China from the writer of Shanghai Scrap. We need to build a closed-loop material economy, and there are pieces of it around today. This is one of them. Mountains of fist-sized shards of shredded cars, sorted manually by women who are earning more than your average Chinese college grad. Amazing photos.
A good piece from The New Yorker on what makes dense urban areas intrinsically better for the environment than suburbia or back-to-the-land fantasies. More people closer together need less transportation to go about their daily lives. High density buildings need less energy to stay comfortable inside because they have less surface area for the enclosed useful space. More resources can be effectively shared when lots of people are close together. The author, David Owen, has a whole book on the topic, entitled Green Metropolis: Why Living Smaller, Living Closer, and Driving Less Are the Keys to Sustainability. Cities have their problems, but often they aren’t the result of density directly. Poor air quality in cities, for instance, is almost entirely the fault of motor vehicles.
I’ve been looking, apparently in vain, for a good book (that’s not in German!) detailing Passive House building and modeling techniques. The best I’ve been able to do so far is Toward a Zero Energy Home, and it must have been pretty good, since I read it cover-to-cover in less than 24 hours. It’s not particularly dense or detailed, but it was a nice quick overview of low energy building systems, with lots of pretty pictures, and a dozen case studies from all over North America, including a couple right here in Boulder.
The goal that the authors have chosen to highlight — “Net Zero” — means that the buildings in question produce as much energy as they consume on an annually averaged basis. This necessarily means that they all have some on-site production, wind, PV, solar-thermal hot water, etc. However, to keep such projects reasonably cost effective, it’s necessary to focus first on energy efficiency measures. Most important among these is a very tight building envelope, much more insulation than code requires, and appropriate glazing for passive solar gain. Then the internal power loads need to be minimized, by using energy efficient appliances and LED or CFL lighting. Only after doing all that is it financially worthwhile to start adding on-site renewable generation, capable of meeting the overall annual energy demands of the dwelling. Financially worthwhile, that is, if you have already decided that you want to create a Net Zero building.
A short video from German home fabricator Hanse House. They do both stock and custom homes, but both are fabricated off-site. The video shows their production facility, and some of the techniques for putting together a building in pieces. It’s pretty awesome. Half robotic assembly line, and half humans, building to what’s essentially a CAD specification, with pipes and wires already laid in place within the structural elements before it gets loaded on the truck that takes it off to the building — or rather assembly — site, where the foundation awaits:
And here’s a time-lapse of one of their Passive Houses being assembled on-site:
I wonder if they do multi-family buildings too. What it would take to get a facility like this operating in Boulder County? Other than a rebound in the housing industry of course.
Life cycle analysis of incandescent, CFL, and LED light bulbs – It’s important to make sure when you’re using a new technology that supposedly saves energy, that you haven’t just shifted the energy consumption from the operational to the manufacturing portion of the product’s life cycle. This study compares three different lighting technologies: incandescent, compact fluorescent, and LED bulbs, and asks what the total energy input is to get ~400 lumens of light for 25,000 hours. Both CFLs and LEDs save about 80% of the energy over incandescent bulbs. For all bulb types, the embodied energy of manufacturing is only about 2% of the total energy consumed over the bulb’s life. CFLs and LEDs were roughly equivalent energetically at the time of this study, but the LEDs produced less in the way of toxic byproducts. The general expectation is that the efficiency of LED lighting will continue to improve, while CFLs are a pretty mature technology. The two best LED bulbs on the market today, with warm yellow light, compatible with dimmer switches, and giving about 800 lumens of light output (equivalent to a 60W incandescent bulb), seem to be this 13W one from Lighting Science ($30) and the 12W Philips A19 EnduraLED ($40). The prices seem high, but as with gas furnaces and boilers, electric motors and pumps, the cost of the electricity or fuel you run through the device ends up dwarfing the capital cost over its lifetime, so paying top dollar for efficiency is worthwhile.
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Continue reading Links for the week of December 9th, 2010
I’m not sure what to make of our willingness to participate in the terraforming of the Earth. To explore it, I’ll consider an alternative history in which Antarctica was marginally habitable, and colonized a million years ago by woolly hominids who developed a Yeti civilization. Our whaling vessels meet up with them in the 1820s, but it’s so cold down there that nobody feels the need to molest them except for few hardy anthropologists, the occasional overzealous missionary expedition, and the usual cohort of scientists who will study the ends of the Earth, no matter how inhospitable. Inevitably, the Yeti spend some late nights with the scientists in their hot tubs watching the aurorae.
They get to talking about the magnetosphere, some atmospheric physics, and the geology of their ice-clad homeland. One day they decide their lives would be better if they could inhabit the entire continent, instead of just clinging to the coastal fringe, and so with the help of some misguided sympathizers, they develop a vast clandestine industrial complex pumping long-lived fluorinated super greenhouse gasses like CF4, C2F6, and SF6 into the atmosphere to warm things up. These compounds are vastly more powerful warming agents than CO2 and methane. They are also long lived atmospheric species, sticking around for up to 50,000 years. If a serious industrial complex were set up to produce and release them en masse, they would close a good chunk of the atmosphere’s thermal infrared window and radically alter the climate for tens of thousands of years. This atmospheric engineering could be done over the course of an election cycle, especially if the Yeti bastards had help from the cold-hearted Canucks and Russkies.
Would the G-20, the OECD or the UN Security Council stand by while a rogue Yeti nation threatened the billions of people who live in coastal cities, or depend on glacial water supplies, all in the name of Manifest Destiny? Of course not. We’d be more likely to bomb their furry white asses back into the Ice Age.