The paper discusses the energy-saving potential of earth-sheltered buildings and the U.S. Department of Energy's research, development and demonstration activities and plans regarding their commercialization.
INTRODUCTION The subject of my presentation--earth-sheltered buildings--involves a happy intersection of a problem and a potential. The problem is well recognized--the scarcity of energy and its rising price. The problem requires that we undertake effective energy conservation programs. In the United States, fully 37 percent of the nation's energy is used in the residential and commercial building sector. This underscores the importance of U.S. building energy conservation programs. The potential is not so broadly recognized. It is the potential of earth-sheltered designs to reduce by up to 30 to 60 percent or more the energy required for the heating and cooling of buildings. The U.S. Department of Energy regards earth-sheltered buildings as the promising alternative it is considering in its innovative structures program. The Department has monitored earth-sheltered building trends, supported research, identified barriers to commercialization, disseminated information, and is applying earth-sheltered designs to one of its own new buildings.
HISTORY The term, earth-sheltered buildings, has not been captured by a formal definition. A good working definition applies the term to buildings with earth protection for 50 percent or more of the area of their roofs and exterior walls. Few of the buildings are entirely underground. but all use the earth to improve their energy performance. The current interest in earth-sheltered buildings is simply the latest chapter in man's continuing struggle to adapt to his environment. The first chapter was the caves inhabited at the dawn of human history. A more elegant version are the homes found in Ajanta, India, that date back to the 5th and 6th Centuries, A.D. A few centuries later, refugees from a crumbling Roman Empire, carved houses into soft, cone-shaped rocks in Cappadocia, Turkey. The Tunisian atrium houses through the century have provided protection from that area's extreme heat. The sod houses of the pioneers of the American prairie were another practical application of earth-sheltered design to cope with severe weather conditions where other building materials were not easily available. A rebirth of interest in earth-sheltered buildings has occurred in the United States during the past two decades. It has been nurtured by various themes. In the early phase, fear of atomic war led to habitable fallout shelters. In the later 1960's and 1970's, the environmental movement led architects to create earth-sheltered designs that were in harmony with the natural environment. The energy-saving benefits of earth-sheltered designs have fanned the rapidly spreading interest in the last half of the 1970's. As director of the Minnesota Energy Agency from 1975 to 1979 when I joined the U.S. Department of Energy, I participated in Minnesota's leadership in the support of earth-sheltered buildings. In the past few years, a state-sponsored guidebook, "Energy Sheltered Housing Design," (Underground Space Center, 1978) has become a best seller, selling more than 100,000 copies. A map of earthsheltered buildings is speckled with activity in all parts of the country with concentrations in Minnesota, Wisconsin and Oklahoma (Vadnais, 1980).