----- Page 12 RAIN August/September 1979 Not to upset the solar applecart, but by now it should be a familiar theme to RAIN readers that the right tools applied in the wrong context will do nothing to solve our problem~- and may even exacerbate them. The following article by Peter Calthorpe and Susan Benson, reprinted from Progressive Architecture, April 1979, couldn't have come too soon. Taking the cold facts on the costs ofurban sprawl (see RAIN, May 1976) one step further, they argue convincingly that without reworking the gluttonous energetics of typical development patterns, self-styled "solar suburbs" could condemn us to repeat the mistakes of the past under the guise of saving a little energy. There are many other factors to consider in reshaping our settlements for sustainability. Lots ofpith hereread it thoroughly. (Thanks to Dave Deppen ) - SA By Peter Calthorpe and Susan Benson The sohr shadow: A discussion of issues eclipsed Every good presentation on solar energy seems to start with some slides of a New Mexico cliff dwelling, such as Mesa Verde. The normal discussion centers on the orientation, shading, solar gain, and sometimes defense aspects of the dwelling. What is not mentioned is the coherence of the community, the density, the shared spaces, and the integration of all daily activities. Only after years of U.S. domination does one find the pueblos beginning to spread over larger areas, losing their center and common ground. The lessons to be learned from the pueblo are more than solar thermodynamics. However, solar energy isbecoming a panacea for our energy ills, the answer of soft technology. There is now a danger of this bright technology casting what is perhaps a long shadow over the broader issues of the patterns of growth and development and their effects on resources, the environment, and people's lives. The form and density of housing, the land use patterns, and the resulting transportation systems have a much greater potential for energy savings than any solar applications. If our community scale development is rational, residential solar applications need provide little more than marginal improvements. Development must be seen in a social) political and environmental context in which solar and other alternative technologies are toolsJor new settlement patterns rather than compensationsJor theJaults oj the old . .. A building is tied to energy use not only by its structural and mechanical design, but by its connections to employment areas, community services, and by its implicit infrastructure: the amount of pipes, roads, and utility wires it demands. Since the Second World War the predominant symbols of our progress have been the growth of suburbia, freeways, and highrise office buildings. These developments create an infrastructure and a development pattern which must be rethought at the same time that alternate energy solutions are developed . If they arc not, there \s a danger that solar and othcr alternate energy sourceS may become a mechanism to perpetuate these inefficient pattcrns rather than a means to a more environmentally sound culture. The present emphasis of solar development assumes the continuing expansion of suburbia. The passive home designs, the active syste.!11s modeled at the universities, and a good part of the federal research and demonstration programs are focused on the single-family dwelling. Beyond It has been estimated that if all the single-family homes built between now and 1990 employ passive solar heating and cooling systems, as much oil will be saved as is expected to be recovered from the Alaskan North Slope. However, if the increased number of automobile trips resulting from this sprawling growth between now and 1990 were figured into a net energy analysis, thc savings from passive solar would be greatly outweighed. Fuel for transit is not the only resource demanded in large quantity by single-family suburban development. Land is another. Most common zoning restrictions and development patterns require the single-family dwelling to "float" on its site surrounded by minimum setbacks from the street and neighboring lots. Beyond land and transit, the potential energy savings from solar heating and cooling of buildings is greatly overestimated because of the inherent inefficiency of our most common housing forms. Without solar and with a more severe climate, Sweden employs approximately 50 percent less per capita energy use for residential heating than that used in the U.S. Building scale, shared walls and floors, infrastructure, district heating, and better insulation could greatly reduce the energy demands of new housing. The cost of sprawl A thorough invcstigation of the resource and environmental cost of new developments was made in 1975 by the Real Estate Research Corporation. The study, "The Costs of Sprawl," assesses six model community types most likely to occur on undeveloped land adjacent to existing metropolitan arcas. In the last decade, 70 percent of the growth in this country occurred in such areas. Each community type used in the study contains the same amount of land- 6,000 acres-has 10,000 dwclling units, and a population of 33,000. The communities arc made up of single-family detached homes, clustered single-family homes, townhouses, two-story walk-up apartments, six-story apartments, and a combination of the above. The resulting land use diagrams of the housing types showed a 200 peret:nt difference in the amount of land consumed between the higher- and lower-density housing projects. The comparison yields an identical contrast with respect to capital costs of construction, which reflect resources consumed in budding and to some degree the amount of pollution produced in the process (Fig. 1). The energy consumption of each housing scheme is determined primarily by the amount of automobile use within the development area, combined with the residential heating and cooling consumption . Even though the study doesn't include the dfccts of the development's location with respect to job or town centers, the resulting energy consumption differellCl: between the high50.000 All.OOO 30.000 20.000 10.000 COST (OOI.lARS 197.\ FIG. 1 OEVELC
RkJQdWJsaXNoZXIy NTc4NTAz