By Katherine Salant
Saturday, February 9, 2008
I have devoted many columns to sustainability issues in terms of a single house. But every so often I like to pull back for the truly wide shot. From a global perspective, what is the state of our planet, and how might this affect our housing choices?
There is no better place to get a sense of this than the book "Plan B 3.0: Mobilizing to Save Civilization" by environmentalist Lester R. Brown. His ability to make a complicated subject accessible to the general reader is remarkable, and he presents surprisingly recent material, frequently citing reports and statistics from just a few months ago.
Of the topics Brown covers, renewable energy is the most directly related to home building. The application of the rest of the book to home building requires some reading between the lines, but not much.
As Brown cites one stark statistic or report after another, it's clear that we cannot expect business as usual in any endeavor. The pressure exerted on the Earth's natural systems by 6.6 billion people and their basic need to eat, as well as by the nearly universal desire for a modern lifestyle, will eventually affect the supply and price of almost every material.
Even the simple desire for paper will have a profound effect on home building. To cite one of Brown's many statistics, if the consumption per person in China reaches the same level that it is in the United States -- a not-unlikely possibility by 2030, he argues -- the people of China will need twice as much paper as the entire world now produces.
And China is only one country. The people of India and many other developing countries will also want paper. We in America can go paperless with a vengeance and become ardent recyclers, but the demand for wood pulp will still force change in many directions, including the way we build our houses.
Brown discusses in some detail the many ways that human activities, on a scale unimaginable 50 years ago, are wreaking havoc with all our natural systems: our forests and croplands, our rivers and lakes, our oceans and air.
He follows this with a presentation of achievable solutions. He is generally optimistic about the future, if we act now.
A very bright spot is the potential for renewable energy to control global warming. This chapter should be required reading for every homeowner and builder, because climate change and buildings are closely connected.
In the United States, about 43 percent of carbon dioxide emissions, the principal component of greenhouse gases, are building-related. Half our buildings are houses. Some of these emissions are produced on-site by gas-burning furnaces and water heaters, but most are produced off-site at power plants that run on coal or natural gas.
Huge efforts have been made to reduce home-energy use and consequently greenhouse gas emissions. There are, however, more than 80 million houses in the United States.
Brown discusses a number of alternate approaches that involve going to the source and changing the way local utilities generate electricity. By using existing technologies, we can power our entire national electric grid with clean energy tapped from the sun, the Earth and moving water.
Some types of clean energy have been used by individual homeowners for some time. For example, American homeowners have been tapping solar heat for domestic hot water for decades, though not in great numbers. Recently, some have been adapting their solar collectors to heat their houses, too.
When the heat of the sun is highly concentrated, it can be used to power turbines that produce electricity. The huge equipment outlays could be undertaken only by a public utility and such a project would be feasible only in an area with little cloud cover and plenty of sun. The Southwest has the right climate, and Brown cites studies showing that this region has the potential to provide seven times the current U.S. generating capacity from all sources.
When the Earth's heat is concentrated in certain geological formations, it can also be tapped to run turbines that produce electricity. The western United States, it turns out, is one of the world's "hot spots" in this regard. Utilities in several western states have about 60 projects in development or under construction.
Homeowners almost anywhere in the country could tap geothermal energy for home heat, but this option is uncommon because of its high cost relative to conventional heating systems.
High cost has likewise affected household adoption of photovoltaic systems, which convert solar energy directly into electricity. Because of the cost, photovoltaic systems are feasible only in places where the state government or local utility subsidizes them.
Moving water, commonly known as hydropower, is another clean energy source. Most hydropower is generated by turbines incorporated into huge dams in river valleys, but "hydro" can be small-scale as well. Individual homeowners who live by small streams can install a "mini-hydro" turbine that doesn't require a dam.
More exotic types of hydropower capture the energy in tidal waters and waves. A wave project has been proposed in California, and tidal projects are being planned on both coasts.
The wind coming off the Great Plains or off either coast could supply enough electricity to power the entire country. Wind turbines already dot the countryside here, as well as in Europe and Asia, and world demand for turbines is huge. To meet it, Brown suggests mass-producing them by adapting idled auto assembly plants.
Brown stretches the definition of "renewable resource " to include the endless stream of waste that we produce because it, too, can be used to generate electricity. There are 89 U.S. plants burning garbage to provide electricity to 6 million customers. Corporations and local utilities are also generating electricity with methane captured from rotting material in landfills.
In sum, there is a renewable energy solution for every utility and every homeowner. The entire country could be drawing clean electric power by 2020 if we make it a priority now, Brown says.
"Plan B, 3.0: Mobilization to Save Civilization," by Lester R. Brown, is published by W.W. Norton and Co. The book and updates can also be downloaded from the Web site of Brown's Earth Policy Institute,http://www.earthpolicy.org.
Katherine Salant can be contacted via her Web site,http://www.katherinesalant.com.
¿ 2008 Katherine Salant