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GSBN:embodied energy



In regard to embodied energy, here's an excerpt from a recent ASES (American Solar Energy Society) publication:
   Tackling Climate Change in the U.S.: 
   Potential Carbon Emissions Reductions 
   from Energy Efficiency and Renewable 
   Energy by 2030  

 This is available for download at www.ases.org

This comes at the embodied energy issue a bit differently, talking about it from the standpoint of how many years of operating energy the embodied energy of a typical house represents and the total GHG emissions over the life of a house. They say 8 to 10 times the annual operating energy. 

For many years I've watched and occasionally participated in a debate about the importance of reducing embodied energy of buildings. A lot of people who look at the relative size of operating versus embodied energy say that the magnitude of the operating energy makes the embodied energy insignificant. I've argued that embodied energy is far from insignificant - it's large and operating energy is typically astronomical - the hugeness of the one does not make the other smaller, it just makes it seem smaller. That is not to say that it might not be wise to focus on operating energy as the first priority, but I've never agreed with those have argued to just ignore it. For one thing, that assumes that we're always going to have the energy or be able to afford it so that we can drag resources all over the planet from wherever we find them to wherever we want to use them and process them to whatever degree meets our desires or particular standards.

David Eisenberg

  Building Envelope Embodied Energy

  The complexity of calculating embodied energy has given rise to a wide range of
  estimates. The Consortium for Research on Renewable Industrial Materials (CORRIM)
  was recently formed to examine the environmental and economic costs of building
  materialsâ??from tree planting to building demolition [14]. Results show that the
  buildingâ??s embodied energy equals about 8 to 10 times the annual energy used to heat
  and cool it and that the GHG emissions range from 21 to 47 metric tons over the
  life of a house. The best way to reduce this significant embodied energy in a building is
  to salvage and reuse materials from demolished buildings, even considering the extensive
  cleaning and repair often required of the salvage materials [15].

  The building design, size, regional material sources, and framing material selection all
  greatly affect the embodied energy and GHG emissions. The CORRIM compared two house
  designs (wood framed versus concrete or steel framed) and found that for the same
  amount of living space, a wood frame house contains about 15% less embodied energy
  and emits about 30% less GHGs than does either a concrete frame or a metal frame
  house [16]. Other studies in this area have reached similar conclusions [17]. Nonetheless,
  optimizing the appropriate mix of low-GHG building materials will require project-specific
  analysis. For example, wood can store carbon that would otherwise have been emitted to 
  the atmosphere. Concrete can reduce operating energy consumption by providing thermal 
  mass to buffer temperature swings. Metal frames may contain up to 90% recycled material.

14. Mumma, T., â??Reducing the Embodied Energy of Buildings,â?? Home Energy Magazine
Online, January/February 1995. Referenced May 2, 2006. Available at
<a  target="_blank" href="http://homeenergy.org/archive/hem.dis.anl.gov/eehem/95/950109.html";>http://homeenergy.org/archive/hem.dis.anl.gov/eehem/95/950109.html</a>

15. Lippke, op. cit., 2004. [Environmental Performance of Renewable Building Materials,&#xE2;?? Forest Products Journal 54(6), June 2004, p. 819. Referenced May 2, 2006. Available at
<a  target="_blank" href="http://www.corrim.org/reports/pdfs/FPJ_Sept2004.pdf";>http://www.corrim.org/reports/pdfs/FPJ_Sept2004.pdf</a>]

16. Energy and the Environment in Residential Construction, Sustainable Building Series
No. 1, Canadian Wood Council, 2004. Referenced May 2, 2006. Available at
<a  target="_blank" href="http://www.cwc.ca/pdfs/EnergyAndEnvironment.pdf";>http://www.cwc.ca/pdfs/EnergyAndEnvironment.pdf</a>

17. &#xE2;??Research News,&#xE2;?? Lawrence Berkeley National Laboratory, May 16, 2003. Referenced
May 2, 2006. Available at
<a  target="_blank" href="http://www.lbl.gov/Science-Articles/Archive/EETD-aerosol-injection.html";>http://www.lbl.gov/Science-Articles/Archive/EETD-aerosol-injection.html</a>

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