Low hanging fruit

I read this article on BBC and reiterated to myself. Existing buildings represent the biggest opportunity to save energy. Saving energy in buildings can be one of the easiest ways we can save the environment. However, what keeps this goal distant is realization of tangible financial benefits to building owners and users/occupants!!! LEED rating does help by providing the necessary publicity/marketing pitch. What other drivers can we think or enact? Federal , state, municipal mandate?!!

Check the article I am referring to, http://news.bbc.co.uk/2/hi/science/nature/7288320.stm