President Obama ordered federal buildings to triple their original renewable energy goals equating to a 20% renewable energy mandate by 2020.
http://www.cnbc.com/id/101249061
Most of the language implies that the only way to accomplish this is to increase the agencies dependence on renewable energy which is more expensive. However, if the building can reduce it’s dependence on traditional carbon emitting energy sources to heat, cool and light their buildings then this would minimize the amount of renewable energy needed to satisfy the building requirements.
For example:
If a building uses a total of $1.34 per square foot on electricity to heat cool and light the building then they would have to purchase at least $.27 per foot from renewable sources. By reducing the building consumption by a typical 23% using RetroWAL, then only $.20 per square foot would need to be purchased or created onsite.
http://www.nationalgridus.com/non_html/shared_energyeff_office.pdf
Rather than spend building funds on solar panels or other renewable technologies, the best move it to improve building energy efficiency by a number of sources just after the building is benchmarked in order to achieve this 20% renewable energy goal most cost effectively.