UN say cities are green, need to be greener (pdf). Cities provide higher standards of living, and more economic opportunity with less energy, materials, and land use. They house 50% of the world’s people, but account for 60-75% of the world’s emissions, not because they’re inefficient, but because city dwellers are disproportionately rich. Interesting data points: Tokyo and Paris dwellers emit half as much carbon as New Yorkers or Londoners. São Paulo is as rich as Mexico City but with 1/3 the emissions. Delhi is 1/3 as rich as São Paulo, but with the same emissions.
Tag: energy
When do fuel costs actually matter?
Kim Stanley Robinson gave a fun talk at Google a couple of years ago in which he brought up the possibility of large, slow, wind powered live-aboard bulk freighters, among other ideas. I was reminded of it by this post from Alex Steffen. Especially for commodities like coal, grains and ore — non-perishable goods that get carried in bulk carriers — what matters is the net flux of materials and the predictability of supply. More (or larger) slow ships can deliver the same flux as fewer high speed ones. International contracts for these goods can span decades. If fuel prices became a significant portion of their overall cost, it would be worthwhile to make this kind of ships-for-fuel substitution. However, it turns out that fuel is a vanishingly small proportion of the overall cost of most internationally traded goods.
Our neighbors in Pasadena moved back to Thailand, and packed their entire household into a single half-sized shipping container. The cost to get it from their home in SoCal to their home outside Bangkok was $2000. Their combined airfare was probably a larger fraction of the cost of moving across the Pacific. You can get a full-sized shipping container moved from point A to point B, anywhere within the global shipping network, for several thousand dollars. If your cargo is worth significantly more than that, then you don’t have to worry about Peak Oil destroying your business. For a typical container carrying $500,000 worth of goods, the shipping costs (not all of which are related to fuel!) represent about 1% of the final costs of the goods. If fuel prices were to go up by a factor of ten, the shipping costs would still only represent 10% of the overall cost. This would have an effect on business, to be sure, but it would not cause global trade to collapse.
The Box That Changed the World
The cost of moving a shipping container between most any two points on Earth is about $5000, and only part of that cost is fuel. So if your container of goods is worth much more than that, then their price and the viability of your business is not going to be particularly sensitive to the cost of liquid fuels. You can pack half a million dollars worth of manufactured goods into one of these boxes. Increase the price of oil by a factor of ten and the cost of those goods goes up by 10%. Annoying? Sure. World changing? Hardly.
Green Manhattan
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.
Into Eternity by Michael Madsen
I am now in this place where you should never come. We call it Onkalo. Onkalo means hiding place. In my time it is still unfinished, though work began in the 20th century when I was just a child. Work will be completed in the 22nd century, long after my death. Onkalo must last 100,000 years. Nothing built by man has lasted even a tenth of that time span. But we consider ourselves a very potent civilization.
If we succeed, Onkalo will most likely be the longest lasting remains of our civilization. If you, some time far into the future find this, what will it tell you about us?
It isn’t often that you find people seriously thinking about deep time in a concrete way. Usually it’s abstract, just a thought experiment, not an engineering problem or a gut wrenching moral quandry. But this is apparently not the case for the Scandinavians who have taken on the task of storing their spent nuclear fuel. Finland has decided to go forward with permanent storage, in a typically responsible, deliberate, earnest Nordic way.
Construction of a Canadian PassivHaus
A great slideshow with captions showing the construction of a PassivHaus in Ottawa. Relatively high density, and relatively high end. I’d love to build something along these lines… and live in it.
Energy Efficiency and Economics at Walnut Mews
Our condo HOA had a meeting last fall, and somebody brought up selling the flat plate collectors on the roof that are part of our defunct solar thermal hot water system. The 750 gallon cylindrical storage tank rusted out in 2003 after 20 years of service. The outbuilding that houses it was basically built over the tank, so swapping it out for a new one would have meant either chopping the thing up in place with a cutting torch and building a new one on site, or removing the roof, which nobody was keen on. Some plumbing got re-routed and the tank sits there still, derelict. It was also mentioned that the main boiler for our hydronic district heating might be nearing the end of its days. I volunteered to look into whether it would make economic sense to repair the solar thermal system, and what the options were for the boiler.
Given that flat plate solar thermal collectors generate an average of about 1kBTU worth of heat per day per square foot (according to the US EIA), and given that we have about 250 square feet of collecting area (nine 28 square foot panels), the current system ought to collect something like 250kBTU/day. Our current boiler consumes 520kBTU/hr worth of gas, meaning that the solar thermal system could at best displace a half hour’s worth of operation each day. Gas costs about $8/million BTUs, so the boiler costs about $4/hr to run. If we assume optimistically that system losses are negligible, and that the boiler runs at least half an hour a day 250 days a year (it was only hooked up to the baseboard heating, not the domestic hot water) then the solar thermal system is capable of displacing something like $500 worth of gas each year. This is a best case scenario though, since the hydronic system needs water that’s hotter than the flat plate collectors can make it (so the boiler will have to do some work to boost the temperature) and because the system losses are almost certainly non-negligible.
Still, $500/year might be a significant savings. To know whether it’s really worthwhile, we need to know how much it will cost up front to get this savings, and how long we ought to expect to be able to collect it (i.e. what’s the system’s expected lifetime). I got wildly varying estimates of the cost to get the system up and running again. At the low end it was $5000, to leave the rusty tank where it is and put a collapsible storage bladder in the crawlspace. At the high end it was $20,000 to remove the old tank and build a new spray-foam insulated stainless steel one in its place. I used this calculator to sanity check my energy numbers above (which don’t seem crazy), as well as the estimates. It suggests that all in, the total system cost including installation would be something like $28,000. I suspect that a plastic bladder in the crawlspace wouldn’t be as efficient or as durable as the new stainless tank. For the sake of argument, let’s say the cheap option will only last 5 years, and the expensive one will last 30 years. The original tank lasted about 20 years. Here’s what it looks like today:
Continue reading Energy Efficiency and Economics at Walnut Mews
The (HVAC) Elephant in the Room
A look at the difficulties of getting good HVAC design in high performance homes. Most HVAC professionals are not familiar with the design requirements of very energy efficient homes with tight envelopes. Most rules of thumb and the very basic modeling that is done in support of sizing the systems implicitly assume a “code” home… which is the least efficient house you can build without getting sued. Oversized systems cause different problems than undersized ones, but they’re still significant problems. As high performance homes become more common, more people are running into these issues. Better contractor, builder, and homeowner education is needed.
Retrofits pick up the pace
A look at the current state of Property Assessed Clean Energy (PACE) financing across the US. Legislation enabling this financing mechanism has been passed in half the country, and implemented at the city or county level in Berkeley and Boulder among others, but because the Federal Housing Finance Administration (Fannie and Freddie’s boss) chose to treat this particular property assessment as a lien, all the programs have been frozen since last July. Lawsuits and legislative fixes abound, but in the meantime, people are struggling to find other financing mechanisms for these financially (as well as ecologically) worthwhile investments. More background available at Pace Now.
Undercover anti-protest cop in UK goes native?
The Guardian is reporting that an undercover police officer who infiltrated the group of protesters that conspired to shut down the Ratcliffe on Soar coal fired power plant may have “gone native” after seven years with the group, taking part in, providing logistical support for, partially financing, and eventually playing a central role in planning their actions. The prospect of the officer aiding the legal defense of protesters who remain to be tried, or at the least, having the role he played in the organization exposed, has apparently led to the collapse of the case. The only really surprising part about all this is his apparent remorse.