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Sustainability and Embodied Energy
Sustainability means different things to different people, and because of this is it very difficult to define. Environment Magazine author Alex Farrell observes that there are two popular definitions. One is that the natural resources of the earth are limited, and we must strive to live within the limits the environment imposes on us and preserve these resources for future generations. The second view of sustainability states that we must work to balance social, economic, and ecological goals so as to meet the human needs of health, education, political freedom, and material needs. Mr. Farrell examines both points of view and then defines sustainability as "improving the quality of human life while living within the carrying capacity of supporting ecosystems."
How does the concept of sustainability relate to the building industry? The Energy Star Home Builders Guild observes: “A typical residence in the United States produces more air pollution than a car.” Energy consumption management and pollution control are key factors in achieving the goal of sustainable development on our planet.
The Environmental Protection Agency has an Energy Star Homes Ally Program that works with building professionals and homeowners to achieve their goal of preventing pollution by encouraging energy-efficient construction. The Energy Star Homes Ally Builders Guide lists the benefits of building a home that meets the Energy Star standards.
Energy Star Homes use at least 30% less energy than a home meeting the National Model Energy Code.
In these ways homeowners can contribute to the goal of "improving the quality of human life while living within the carrying capacity of supporting ecosystems."
The concept of conserving energy can be taken one step further by taking a “long term” approach to analyzing total energy consumption. This concept is called embodied energy. In her article titled “Reducing the Embodied Energy of Buildings”, Tracy Mumma defines embodied energy as, “An assessment that includes the energy required to extract raw materials from nature, plus the energy used in primary and secondary manufacturing activities to provide a finished product. There is embodied energy in any processed product, from a drinking cup to a car. In embodied energy terms, buildings represent a huge, relatively long-duration energy investment.”
Although the article does recognize the fact that measuring the amount of embodied energy which goes into a product is not an exact science, Mumma does offer a few guidelines for those looking to use products that have a lower embodied energy. First she offers a few “rules of thumb” to use when making purchasing decisions:
Embodied energy of manufactured products can be lowered at any stage of production.
She stresses using common sense above all else when she writes: “After all the rules of thumb have been applied, the best hope of reducing embodied energy in buildings comes down to the reasoned actions of responsible individuals. Designers, builders, homeowners, manufacturers and policy makers can act to reduce the level of embodied energy in building materials in a number of ways.”
Polyurethane Foam and Energy Efficiency
Using FOAM-TECH’s Superinsulation can provide you with an energy-efficient building which complies with the Energy Star standards, mentioned above. Some characteristics of foam insulation which meet the goals required for both the sustainability and embodied energy mandates are:
Farrell, Alex, “What does sustainability really mean?”, 1998. Environment Magazine, Heldref Publications, Washington D.C., November.
Mumma, Tracy, “Reducing the embodied energy of buildings”, 1995. Home Energy Magazine Online, Berkley, California, January/February.