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Archive for August, 2009

Last week, for the first time in my life, I sat on my front porch and watched the sun set over the trees at the far edge of the open lot just to the west of my house. The day before, and all the days before that, the sun set nearly an hour earlier, over the high sturdy bulk of Brunswick’s old high school.

Crunch, crunch, crunch went the mechanical dinosaurs, chomping to bits course after course of bricks, slices of glass, and cubes of granite. Built in 1937, the school was occupied for about 60 years before the town’s high-schoolers were relocated to the outskirts of town.

From the decaying rubble pile of this old building across the street, will grow, for better or worse, a new elementary school, slated to open in 2011.

On the better side, the new building will be very energy efficient. Heating and cooling will be provided by a geo-thermal system which generates energy by exploiting the differences in temperature above-ground and underground.

The roof of the new building is to be light in color. By reflecting radiation from the sun, rather than absorbing it, light roofs can significantly cut cooling costs, extend the life-span of the roof, and reduce the heat that builds up in developed areas–all of which will lower carbon emissions and help combat global warming.

Perhaps best of all, the building is centrally located in town, alleviating the need for long bus trips and commutes.

Yet it is surprisingly difficult to conclude that this new energy efficient building will result in a net gain for the environment. It is clearly true that the building will use less energy per square foot than the older buildings Brunswick’s students currently attend.

It is less clear that the new building will use less energy per student. The new building is not simply a greener version of the older ones. It provides services the older buildings did not, such as more space per student, better ventilation, room for new programs, enhanced community space, more gym space and kitchen facilities.

One might fairly ask if all these services, which use energy and therefore gobble up some of the savings provided by a more efficient building, are correlated with better educational and health outcomes.

To further complicate matters, from an environmental perspective a simple comparison of energy use in newer and older buildings is not enough. To actually help reduce global carbon emissions, a new building must first save the equivalent of all the energy used in its creation as well as the energy used to demolish and dispose of the older building it replaces.

According to architects working on historic preservation, a new efficient office building must operate for 40 years before it has saved enough energy to offset the carbon emissions generated in its construction. If an old building must be be torn down first, then the new building must operate for 65 years just to break even.

This fact gives one pause when the U.S. Department of Energy reports that the median life-span of an office building is about 73 years.

Even when the energy used in demolition and construction are factored in, it can still be tricky to evaluate the overall environmental impact of new buildings. Consider this: the Chesapeake Bay Foundation Environmental Center, built in Annapolis in 2000, uses an impressive 70% less energy than a typical office building, but may still not have resulted in a net environmental gain.

The Foundation’s old offices were in the middle of town, while the new building was sited 10 miles out. An analysis by the Environmental Working News concluded that the new center, one of the most efficient buildings ever built, may have only succeeded in offsetting emissions from the increase in employee commuting.

Of course, if you’re going to put a new building 10 miles from a town center, it’s important to make it as efficient as possible. However, if we are to succeed in reducing our global warming emissions we have to do better than holding our own and we have to do better than implementing solutions with 60+ year energy paybacks. It is not enough to simply exchange an inefficient something for a more efficient something.

The new wildly popular Cash for Clunkers bill, recently re-infused by the legislature with another two billion in taxpayer money, comes to mind. Under the terms of this bill, folks can receive a rebate of $3,500 to $4,500 for trading in “clunkers” (defined as vehicles getting less than 18 miles per gallon) for more efficient vehicles (defined as vehicles getting as little as 19 to 22 miles per gallon).

Although marketed as a means to fight global warming, the bill may do just the opposite. Simplistically, it’s better to replace an 18 mile per gallon (mpg) car with a 19 mpg car. Yet, to reduce total carbon emissions the new car has to not only have better fuel economy than the old car, but it has to pay back the energy used in manufacturing itself as well as the energy needed to dispose of the old car. At 19 mpg, a new vehicle may never break even.

The Union of Concerned Scientists concludes that in order to generate a unambiguous benefit for the environment, Cash for Clunkers rebates should only apply to folks trading in a vehicle that is at least 8 years old and getting a new vehicle that is in the top quarter of efficiency rankings for its class. Without these measures, the bill may wind up increasing global warming emissions.

To determine if a sexy new program (or building or solar array or biofuel) truly reduces global warming emissions we need to do careful scientific analyses and we need to rely on those analyses to set policy. The results are not always obvious.

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Getting lost in the Maine woods is not difficult. Trails twist crazily through gullies and over hills while tangled underbrush makes walking off-trail tortuous. The high ridges from which you might orient yourself are typically wrapped in dense thickets of trees.

Thousands of feet up in California’s Sierra Nevada mountains, it’s a lot harder to lose your way. The landscape is so wide open and the scale so expansive, that you could walk for half a day and still be in sight of the pass you’d hiked over that morning.

Yet, during a backpacking trip in the high Sierra years ago, I found it oddly uncomfortable to venture off the trail. My friends, with a lifetime of experience hiking thereabouts, simply laughed. They pointed out that there were no trees to obscure our view. They showed me the many peaks we could climb to find out where we were.

I could see that they were right. I knew the trail we were leaving offered little in the way of security given how lightly travelled it was. I knew we had a good map and compass, and I knew we’d be on rock surfaces the entire time (thereby eliminating any worries about stomping on fragile alpine plants).

But stepping off the trail, irrational as it clearly was, felt like cutting my ties to the rest of civilization. The trail, the only sign that other humans had been here before, offered me a measure of comfort in that omnipotent wilderness. It granted me safe passage through a potentially hostile landscape.

Most of us would say we love being out in nature. But what we really mean is that we love nature unfanged and declawed. We like to get as close as possible while still feeling comfortable and without feeling threatened: wild, but not too wild.

Many issues in managing our natural places stem from this dichotomy: the wilder the wilds, the fewer people can enjoy them. But conversely, the fewer concessions made for people, the more the animals and plants are likely to thrive.

We struggle with questions such as what to do with potentially dangerous critters (such as bears), whether to put in more campsites and trails, how much to publicize natural areas, whether to limit access, and how much parking to provide.

I pondered these issues during a recent annual family reunion in Acadia National Park. Most of the time I love Acadia. It mixes wildness and comfort in a way that is unique unto itself. At a relatively small 40,000 acres, the park is densely laced with hiking trails and carriage roads.

The latter are 16-foot wide gently graded gravel trails built for horse-drawn carriages and now limited to walkers, bicyclists, and horses. Stream crossings and gorges are spanned by glorious stone bridges. These roads and bridges were funded (and largely designed) by John D. Rockefeller in the early 1900’s. Rockefeller’s express purpose in building them was to provide the public access to the grandeur of Mt. Desert Island without the disruption of car traffic.

The carriage roads were laid out with the twin goals of fitting seamlessly into the landscape and of affording the best views of ocean, lakes, waterfalls, and ridges. These goals were brilliantly met. Traveling through the park on a Rockefeller carriage road is like wandering through a painting — not because of the park’s spectacular natural beauty, but because this beauty has been captured and framed by the roads.

Acadia is the embodiment of nature defanged. Although it is one of the most visited national parks, it’s still remarkably easy to get away from the crowds. (There must be some formula relating distance from parking to number of people about).

On a gray day with a threat of rain, the carriage trail up Day’s Mountain, for example, is almost always deserted, even in mid-summer. Of the many times I’ve been at the summit, I’m usually the only soul up there. There is exhilarating natural beauty all about, side by side with comfort and civilization built into the very experience of arriving there, in the way the views are calculated to appear and disappear with curves of the road. The park is entertaining more than it is truly wild.

Sometimes, I’m conflicted about Acadia. Was it a good decision to have carved up the wilderness to build this giant playground? At the same time I love to see the ease with which this park allows a larger variety of people into the woods and up the ridges than can usually engage in such a setting. These experiences are typically reserved for those fit enough to hike for hours into the backcountry.

My kids and I recently found a small pond near our house, tucked away in part of a new development. The edges of the pond are landscaped with native plants: Joe-Pye weed, wild blueberry, Queen Anne’s lace, milkweed, willow. Although the buffer is only a few feet wide, in it is a thriving ecosystem teeming with frogs and insects.

At this pond, I can sit in civilization, on a lawn, in a chair, reading my book, while just a few feet away my kids disappear (literally) into the tall grass jungle to catch frogs and collect cicada skins. Surely the easy access to such natural richness is nurturing my children’s fascination with the wild just as Acadia’s wide open welcome nurtures everyone who visits.

I’d be hard pressed to advocate for carving up another pristine wilderness to make another Acadia; I admit I’m biased toward protecting what’s left as best we can. However, Acadia reminds me that there should be places where every type of person can step away from the traffic, catch a frog, walk along a ridge over the ocean, and see, as I did coming around a bend in Acadia with my daughters last month, a quiet lake with a turtle on every rock.

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