Monday, November 24, 2008

Making suburbia sustainable.

The Oil Drum
A Resilient Suburbia? 3
Weighing the Potential for Self-Sufficiency
Posted by jeffvail on November 24, 2008 - 12:07pm

A backyard garden in Oregon

Over the past two weeks, I have examined the challenges facing suburbia in a post-peak world. I’ve argued (in Part 1) that financial reality will prevent us from building an alternative to suburbia, and (in Part 2) that the superficial transportation issues facing suburbia are better viewed as a much broader economic threat posed by peak oil that equally threatens urban and suburban living. In this post, I’ll look at some of the unique advantages of our present suburban arrangement—is it possible that suburbia not only won’t be abandoned post-peak, but that peak oil will act as a catalyst for the adaptation of suburbia into a flourishing, vibrant built environment? I think it’s possible, but that it will be challenging. In this post I’ll explore this possibility—both the potential, and the challenges—of creating A Resilient Suburbia...

Food

...suburbia can realistically provide around 50% of its food, can act as a localized buffer against disruptions, and can provide a high percentage of vitamins, minerals, flavor, and culturally-important foods.

Critically, while attaining self-sufficiency on suburban lots may not be easy, it is certainly more practical to obtain a significant degree of food self-sufficiency in suburbia than it is in urban settings. This isn’t to say that urban areas shouldn’t explore gardening possibilities—it is simply to point out that suburbia’s food-production potential is an asset when compared to urban settlement. Whether or not its food-production advantage outweighs its transportation disadvantage is not clear—but more on this later.

Water

In the next century, water will be one of the most critical, and scarce, resources for many parts of the world. Even in those areas where there water supplies are plentiful, there is a significant energy requirement to build, maintain, and operate the infrastructure required to gather, store, transport, and purify water. How realistic is it for suburbia to provide its own water, both for domestic use and for suburban gardening?

Many people will initially object to the potential for suburban water self-sufficiency on the grounds that rainfall is erratic, and that some areas of the country are quite arid. While it isn’t the Atacama Desert, skeptics should read Brad Lancaster’s excellent guest-post on rainwater harvesting in Tucson, Arizona (average 12” of rainfall per year). For several years now, Lancaster has been using simple rainwater harvesting techniques at his modest suburban Tucson residence to harvest sufficient rainwater for both domestic needs and to sustain an impressively productive garden. The average suburban home has a roof area of roughly 2000 square feet (garage roofs and overhangs count here, but not on home square footage). In Tucson, with 12” of rain per year, that catches as much as 14,000 gallons per year (or 40 gallons per day)—more than enough for frugal domestic usage by one family, though certainly not enough for several hot baths, a backyard pool, and multiple loads of laundry daily. In wetter climes—say, Ohio with 37.77 inches per year on average--the potential is even more clear...

Energy

...Based on a very informal survey of conservation-aware households, a WAG is that 20 KW-Hours per day, per household is realistic (probably conservative) for suburban electricity usage with some focus on conservation. Using the rough metric of 1300 KWh per year from 1 KW installed capacity, our hypothetical suburban household would require 5.6 KW of solar capacity. In other words, there’s plenty of roof space in suburbia to meet suburbia’s electricity demand. Two important caveats: 1) such a system won’t provide power when suburbanites currently use it (a net-metering system paired with other forms of generation would be necessary), and 2) while some households use electricity for home heating, water heating, and cooking, in many areas and homes it simply isn’t realistic to heat a home with 5.6 KW of installed solar power only...


Not with forced air, certainly. But heated floor tiles use way less energy and get the house just as warm. Since heat rises, you may not even need to install any tiles on the second floor.

...Additionally, it isn't realistic at present to think that we'll be able to put enough solar panels on our roofs to charge the batteries on the twin electric-Escalades sitting in our garage for the daily commute to work. I increasingly believe that suburbia can be resilient and sustainable, but not as a mere "Star-Trek" version of the present. Rather, by minimizing our travel requirements at the outset, and then transitioning to high-efficiency vehicles, ridesharing, bicycles, and especially electrified rail for remaining journeys, suburbia can adjust to a radically lower transportation energy-budget.

So once again, we see a sustainable future doesn't generally involve private automobiles. GM will have to find something else to do with their time.

Conclusion

Suburbia has a significant potential to provide its own food, water, and energy. It won’t be as simple as snapping our fingers. And it likely won’t be possible for suburbia to consistently produce 100% of its needs. But I think one thing is quite clear: the potential increase in suburbia’s self-sufficiency is significantly greater than the potential for urban areas to increase their self-sufficiency in food, water, and energy. We can argue the degree to which this is the case, but I’ll be interested to see if anyone seriously disputes the issue generally. If we accept that suburbia has greater potential for self-sufficiency, and if we accept that suburbia requires more energy for transportation and transportation infrastructure in its current manifestation, then the big question is this: does suburbia’s advantage in potential self-sufficiency outweigh its disadvantage in transportation? It's quite easy to toss out an unsupported opinion on the answer--I won't attempt to do so, and I'll caution that anyone who does, without empirically and irrefutably answering the potential for suburban self-sufficiency, is just guessing. The answer partially turns on the degree to which suburbia can convert itself away from a commuter model and toward a knowledge-based, distributed production model. It also, as I’ll discuss next week, turns on the value of distributed ownership and self-sufficiency as a force in determining the political structure and evolution of civilizations.


Those are some big "ifs," and so far, and it can't all be "knowledge based." A lot of it is going to have to be cottage industry and household economy. But you see, it is doable.

No comments: