Just in time for Earth Day, a new study reveals the metro areas whose homeowners make green living a priority.

According to real estate broker Redfin, San Francisco homeowners are some of the most energy-efficient consumers in the country, as evidenced by their electricity usage and carbon dioxide emissions. The real estate provider indicates that on a per capita basis, San Francisco homeowners produce the least amount of carbon dioxide, and the homes that are for sale boast a variety of eco-friendly features, such as home energy upgrades, solar panels and low-flow faucets.

Also chief among the cities where homeowners put a premium on environmental friendliness is Washington, D.C. Citing the U.S. Green Building Council, Redfin says that a sizeable percentage of the properties for sale in the Beltway area are LEED-certified, which is a green-building program that construction firms use. LEED stands for Leadership in Energy and Environmental Design.

Rounding out the cities with the greenest homes are Sacramento, Boston, Philadelphia, Phoenix, Los Angeles, Seattle, Austin and Portland, Oregon.

Basic ways to be more eco-conscious

There are a variety of ways in which homeowners - no matter where they live - can make their properties more energy-efficient. And it starts with a home inspection that can be performed on one's own or with the help of a licensed professional.

For example, though it may seem hard to believe, a lot of the energy that homeowners waste is when it escapes through the cracks and seams that surround windows and doors. This issue can be corrected, though, with weather-stripping and caulking. By feeling along the lining of windows and doors, this inspection process will help reveal areas where air is escaping, thus requiring some reinforcement.

Another source of energy use are the appliances that require water, such as faucets and toilets. It's estimated that approximately one-third of a home's water supply is devoted to the toilet for flushing and cleaning needs. By installing low-flow toilets, shower heads and sinks, a tremendous amount of water can be saved, as these devices don't require as much water to operate at their peak.

Now that the spring is here, homeowners may be preparing their yards so that conditions are just right for grass growth. Sprinkler systems can help expedite the process but that shouldn't come at the expense of wasting water. To ensure that excess water isn't used, inspect all of the hoses to make sure there aren't any leaks.

Energy-efficient strategies like these can help homeowners save hundreds of dollars in their annual electricity expenses and do a great deal of good for the environment at the same time.