• This chart shows per capita carbon dioxide emissions across the country; greener areas have fewer emissions, dark red areas have the most.

    Credit: PRNewsFoto/Redfin

    This chart shows per capita carbon dioxide emissions across the country; greener areas have fewer emissions, dark red areas have the most.

San Francisco and Washington, D.C., top real estate broker Redfin’s ranking of the country's top 10 cities with the greenest homes. The newly released analysis looked at each city's overall carbon dioxide emissions and the number of homes currently for sale that have green features or eco-friendly ratings. 

Sustainable features included solar panels, low-flow faucets, dual-pane windows, Energy Star-labeled appliances, LEED certification, and new construction by green builders. Below, Redfin supplies information about each top-10 city’s green initiatives: 

San Francisco. In addition to having the lowest carbon dioxide emission rate per capita, San Francisco has a large number of homes for sale with eco-friendly features. One incentive for locals to go green may be Pacific Gas & Electric's rebates, which offer up to $4,000 for home energy upgrades including insulation and air duct sealing. 

Washington D.C. According to the U.S. Green Building Council, Washington D.C. has the most LEED-certified space, which likely contributes to the city's low carbon dioxide emission rates. In addition, the district offers a number of rebates and tax credits for residential energy efficiency, which may help explain the high number of homes for sale with eco-friendly features. 

Sacramento, Calif. Sacramento has the second-lowest carbon dioxide emissions in the country, and new developments have focused on energy-efficient homes, such as the Northwest Land Park, which will build 800 new homes that use net-zero electricity. 

Boston. Mayor Thomas Menino launched an initiative to be "Green by 2015," which includes powering homes using a combination of waste products and solar panels. The city also supports the Energy Positive "E+" Green Building Demonstration Program, which aims to bring green homes to Boston's neighborhoods. 

Portland, Ore. Portland General Electric offers residents the choice to pay a little more for renewable energy options, including wind-sourced power. In addition, Portland residents who want to make their home more green can attend Fix-It Fairs, which offer resources and information to help attendees reduce water and energy usage, among other green initiatives. 

Philadelphia. Even though Philadelphia's carbon dioxide emissions were higher than other cities, it ranked second for homes with eco-friendly features. In 2009 the city passed two laws that advance green building practices. The first requires that new city government buildings meet LEED-Silver Certification, and the second requires all new construction to have "cool roofs" that meet or exceed Energy Star standards. 

Phoenix. As part of the "Green Phoenix" initiative, the city offers a one-time grant to homeowners for making improvements that reduce energy consumption. The city has also received funding to retrofit low-income residential homes with cost-effective energy-saving measures. 

Los Angeles. Homeowners looking to reduce costs associated with air conditioning in L.A.'s warm climate can take advantage of the L.A. County's Energy Loans Program, which offers loans of up to $50,000 dollars with financing as low as 4.99 percent when homeowners undertake home energy improvements. In addition, Energy Upgrade California offers rebates of up to $4,000 to homeowners who make their home more energy efficient. 

Seattle. Seattle residents are known for being eco-conscious, as evidenced by the recent ban on plastic bags, so it's not surprising they'd want their homes to be green, too. Although the city is known for its rain, Seattle receives more sunlight than Germany, the world's leading solar market, and Washington State offers financial incentives for those who generate their own electricity using solar electric systems. 

Austin, Texas. Austin Energy is the nation's top seller of renewable energy, and the company offers homeowners low-interest loans of up to $20,000 dollars for energy efficient upgrades. In addition, the company offers rebates for numerous upgrades, including extra attic insulation, high-efficiency clothes washers, rainwater collection barrels, and low-flow toilets.