Clicking on the interactive map is interesting. One thing leaps out immediately: Low population density correlates to higher energy usage. I can understand why for a couple of reasons:<p>- Apartment/condominiums should be more energy efficient for heating and cooling than single family homes.<p>- A lower density likely means driving farther to work, hence greater auto transportation footprint and less likelihood to use public transportation.<p>The breakdown charts confirm this: San Francisco neighborhoods of single-family homes in the Marina show housing at 15.36, transportation at 20.34<p>While neighborhoods of apartments South of Mission show housing at 2.39 and transportation at 2.89<p>Those two factors alone illustrate a 7x consumption by single-family structures (plus their cars) over apartments.<p>I suspect there is also a strong correlation with household wealth, implying larger homes to heat/cool and more automobiles. So it would be interesting to see that illustrated as well.