Ernst & Young is accelerating its greening efforts as the firm builds its sustainability practice.

Leisha John, Americas director of environmental sustainability at E&Y, stopped by the offices yesterday with tax services partner Stephen Starbuck to talk about the firm’s efforts to go green. They noted that climate change and sustainability are increasingly important concerns for clients, as are energy costs. E&Y is helping them reduce the levels of carbon and making the firm itself greener.

E&Y has been actively working on reducing its own carbon footprint, and now has calculated a baseline from which to work. That includes everything from doing more double-sided copying at the Xerox machine to getting rid of Styrofoam coffee cups at its own offices.

The firm has also been helping clients qualify for government incentives and stimulus money, including a piece of the $2.3 billion in tax credits for clean energy technology projects that the Obama administration recently announced (see Obama Awards $2.3B in Tax Credits to Spur Jobs).

E&Y has been getting some of its own staff involved in green projects as well. The firm set up an “EcoCare” network of over 1,000 volunteers who have been involved in a variety of projects, including building a large recycling center at its Secaucus, N.J., offices, where employees also go for walks through the local marshland.

The firm teamed up with EarthWatch last year and sent a group of about a dozen employees to a Costa Rica coffee plantation to evaluate its environmental and economic sustainability, in part by measuring tree trunks. The firm plans to send another, larger group on a similar trip this year.

To be sure, renewable energy legislation currently seems to be stalled in the Senate and the recent climate change summit in Copenhagen disappointed many in the environmental movement with the lack of specific commitments by the nations that attended, including the United States. However, companies of all kinds still want to reduce their energy costs, and many now recognize that they need to be more effective stewards of the environment.

Accounting firms like E&Y can play a part in helping them to demonstrate their sustainability efforts, which are becoming a key requirement for business partners. In addition, those that operate in Europe can also play a role in the carbon emissions trading system there, and help audit carbon credits to reduce the potential for fraud.