See Greenbiz.com column...
From the executive summary of the report:
Green teams are self‐organized, grassroots and cross‐functional groups of employees who voluntarilycome together to educate, inspire and empower employees around sustainability. They identify andimplement specific solutions to help their organization operate in a more environmentally sustainable fashion. Most green teams initially focus on greening operations at the office, addressing such issues as recycling in the office, composting food waste, reducing the use of disposable take‐out containers and eliminating plastic water bottles.
This focus on operations is evolving and some green teams are beginning to focus their efforts on integrating sustainability into employees’ personal lives, while others are aligning their efforts to support broader corporate sustainability objectives. The business value of integrating sustainability into these three levels includes: cost savings by integrating energy efficiency into the workplace and products and services; attracting and retaining the best and brightest talent who want to work for companies with an authentic green commitment; and increased market share and revenues resulting from a stronger brand and new, innovative green products and services.
For more details.. http://www.greenbiz.com/research/report/2009/12/03/green-teams-engaging-employees-sustainability.