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Richard Moe, President of the
National Trust for Historic Preservation, describes embodied energy
as follows:
"Buildings are vast repositories of
energy. It takes energy to manufacture or extract building
materials, more energy to transport them to a construction site,
still more energy to assemble them into a building. All of that
energy is embodied in the finished structure - and if the structure
is demolished and landfilled, the energy locked up in it is totally
wasted. What's more, the process of demolition itself uses more
energy - and, of course, the construction of a new building in its
place uses more yet."
The Historic 1918
Kasson School is comprised of approximately 30,000 square feet. The
school has approximately 48 Billion BTUs of energy embodied within
its construction materials. That is the equivalent of 384,000
gallons of gasoline. If you tear the building down, all of
that embodied energy is wasted. Demolishing the school would
create approximately 2,400 tons of waste headed to a landfill.
After the building is gone, constructing a new building it its place
requires more energy usage and it also uses more natural resources
and releases new pollutants and greenhouse gases into our
environment. It is estimated that constructing a new
30,000-square-foot building to replace the school releases about the
same amount of carbon into the atmosphere as driving a car 1.7
million miles.
Richard sums up
embodied energy as:
"You
might think that all the energy used in demolishing an older
building and replacing it is offset by the increased energy
efficiency of the new building - but that's simply not true. Recent
research indicates that even if 40% of the materials are recycled,
it takes approximately 65 years for a green, energy-efficient new
office building to recover the energy lost in demolishing an
existing building. And let's face it: Most new buildings aren't
designed to last anywhere near 65 years."
"A
report from the Brookings Institution projects that by 2030 we will
have demolished and replaced nearly 1/3 of all existing buildings,
largely because the vast majority of them weren't designed and built
to last any longer. How much energy will it take to demolish and
replace those buildings? Enough to power the entire state of
California for 10 years."
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