### Image Credits:

1. Alex Wilson

1.
Sep 2, 2009 3:28 PM ET

Special Neighborhoods
by John Brooks

We recently built in a Historic Neighborhood.
They encourage people to work at home....
Two Blocks from the light rail station ...walking distance to the park, downtown, restaraunts and a produce market.

Very pleased that we did not have to tear down an existing home.... ours is a very small lot that was part of a larger estate that "vanished" over fifty years ago.

2.
Sep 3, 2009 3:35 PM ET

You May Have Missed Something:
by Steve A.

With all due respect, I see a possible flaw in your calculations.

You should calculate the total from source energy intensity, not site energy intensity. The efficiency losses of electrical generation production and distribution is on par to being 50% - which is not being calculated in this equation.

There is energy consumed with drilling, refining and transporting oil, but I don't believe it nears the 50% range. Most of oil based energy is lost at the point of use (in the form of waste heat) during combustion. This is why your energy use calcs are so high for autos and so low for buildings.

I have a feeling if he were to calculate his numbers from *source* Btu intensity, it would put the burden largely on the building.

I manage a very efficient office facility, with a site intensity of 42 kBtu/ft2/year. Not bad. But If you do the same numbers from *source* intensity (according to the EPA energystar building calc), that jumps by nearly a factor of 3, to 123 kBtu/ft2/year.

If the average office building consumes 93 kBtu/sf/yr, their source energy needs are on the range of 280 kBtu/sf/year - which is much higher than automobile needs.

3.
Sep 7, 2009 12:15 PM ET

good eye on the source energy
by Brennan Less

Steve, you make a very good point. Here's how I interpret your point: Alex calculates transportation energy as 56.5% (121kBtu/(121kBtu + 93kBtu)) of total building energy intensity, and your source-adjusted figures put transportation energy as 30.2% (121kBtu/(121kBtu + 280kBtu)) of total building energy intensity. There is a difference of 26.3% between these two figures--not insignificant. But let's not lose sight of the real issue here. If any other building element were responsible for 30.2% of total energy intensity, then engineers would target it directly for aggressive load reductions (for example, lighting in commercial buildings). I think Alex is simply pointing out that targeting transportation energy reduction in green design may be more effective than targeting building elements with respectively lower percentages of total energy intensity. I think there is potentially a very interesting economic/green house gas argument to be made here. Enjoy your holiday.

4.
Mar 3, 2010 7:56 AM ET

hayaloglunakliyat
by hayaloglunakliyat

The program’s next challenge is to help push national leaders around the world to consider transportation when putting together Nationally Appropriate Mitigation Actions (NAMAs), the low-carbon, sustainable development plans written by developing nations to receive funding under the United Nations Framework Convention on Climate Change (UNFCCC).