Beginning at the far left, the first bar illustrates that buildings used 40 quadrillion BTU of delivered energy in 2010. If no improvements were made in physical energy use intensity (energy use per square foot), yet the number and size of buildings continued to increase, we’d expect buildings to use 58 quads in 2050. However, the Energy Information Administration (EIA) believes some reductions in energy intensity will continue to occur, reducing our projection of EIA’s 2035 forecast to 53 quads in 2050. From here, our analysis goes beyond what the EIA believes is possible (since its forecasts don’t explicitly include innovation or new policies). We quantify how additional cost-effective energy efficiency (based on findings by the National Academy of Sciences) and smart controls (based on work by the American Council for an Energy-Efficient Economy) could save more. These savings yield the 2050 Reinventing Fire energy use of 20 quads in 2050. From here, we go just one step further to estimate potential further savings from integrative design. The wide range of data and assumptions that go into this last step imply a range down to as low as 16 quads in 2050. All these figures assume 70% more floorspace in 2050 than in 2010.
A- U.S. Energy Information Administration. 2010. Annual Energy Outlook 2010. Washington DC: U.S. Energy Information Administration, May 11. link
B- National Academy of Sciences. 2010. Real Prospects for Energy Efficiency in the United States. Washington DC: The National Academies Press. link
C- Ehrhardt-Martinez, K., K. A. Donnelly, and S. Laitner. 2010. Advanced Metering Initiatives and Residential Feedback Programs: A Meta-Review for Household Electricity-Saving Opportunities. American Council for an Energy-Efficient Economy, June.