Sustainable development practices started as a push, with building owners and occupants pushing the industry to create superior product. Slowly, governmental entities have begun to pull developers in the same direction by offering incentives, such as increased floor area ratios or maximum density. It is inevitable that these entities will ultimately move toward mandates, without incentives, but we haven't reached that point. Attached is a germane article showing recent activities at the federal level.
http://switchboard.nrdc.org/blogs/wfok/tenant_star_market-driven_ener.html
This article is presented for informational purposes only and is not intended to constitute legal advice.