The number of American cities with programs to promote energy efficiency and sustainable building materials has jumped 50 percent from 2007, said the American Institute of Architects Wednesday.

The growth, from 92 cities in 2007 to 138 cities today, reflects the boost in federal spending on energy efficiency in order to cut energy consumption while creating jobs. About 40 percent of the emissions in the country come from buildings, the AIA said in new report.

Western states have the most municipal green building programs – 56 cities in six states. California alone has 47 and leads the nation. The AIA only surveyed cities with more than 50,000 residents.

The central region has 21 cities with such programs and lags behind all other regions in the country, the AIA said. The central region includes states such as Texas, Illinois, Oklahoma and Mississippi.

The AIA's new report, "Green Building Policy in a Changing Economic Environment," outlines the policies and case studies about green building programs in major cities such as Los Angeles, Boston, Nashville and Grand Rapids, Mich.

"Green building" is a broad term and refers to a wide variety of ways to reduce fuel, water and electricity use and cut emissions.

Such efforts could include using more energy-efficient light bulbs and air conditioners, capturing methane gas at landfills, conducting energy audits and choosing materials made from low-carbon sources to insulate or build homes and commercial and government buildings.

The economic slump has spurred the federal government to invest in energy efficiency technologies and projects in an effort to cut emissions and create jobs.

The American Recovery and Reinvestment Act set aside $3.2 billion for giving energy efficiency and conservation block grants to local communities. California, for one, has gotten $49.6 million from this program.

This heightened focus on green building designs and materials have spawned startups developing software, materials and equipment, and services to target this broad market (see Green Pitches: How to Make Money in Green Building Biz, Inside the Green Brick House and Webcor and iCrete Team on Green Building).

Existing, major players in these business sectors, such as Dow Chemical, IBM and General Electric, also have jumped in (see GE Unveils Net Zero Energy Home Strategy and Dow to Roofers: Our Solar Shingles are Coming and IBM Expands Efficiency Offerings).

The AIA assembled a list of recommendations to cities in its report. The suggestions included hiring a sustainability director, removing building and zoning rules that hamper mixed-use real estate developments and the use of gray water systems and, of course, making good use of local architects. 

Photo by design by Weber Thompson in Seattle, a winner of the 2009 Top 10 Green Projects chosen by the AIA.