Start by switching to green power

The easiest way to switch to green energy is to call your current provider and see if they offer an alternative. An increasing number of companies do, harnessing renewable sources like wind and solar power to offer electric service in their markets. This costs more for the consumer, since you’ll pay a premium to offset the money involved in tapping the alternative source, but the price varies: in Sacramento, you’ll pay 5 cents per kilowatt hour or $30 a month for solar, and in Oregon you’ll shell out only .8 cents per kilowatt hour for wind, geothermal, or hydropower. Curious about the options in your state?

Plug in to solar power

There are two kinds of solar power you can use in your home: active and passive. Active solar power is captured through solar cells (also known as photovoltaics), and then stored to later provide heat or electricity-or to supplement a traditional heating or electrical system. But before you buy a solar system for your house, keep a few points in mind: many towns have restrictions on the size and type of collectors they’ll allow; the annual number of sunny days in your climate will affect how much power you can collect (the Southwest usually has the best luck with solar collection); and the system’s cost efficiency varies based on its size, your location, and the amount of power you plan to get from it.

Get passive solar to work for you

The second kind of solar power, passive solar, doesn’t involve the (expensive) photovoltaic cells and mechanical systems of active solar, but still takes advantage of the sun to heat your home in one of three ways: direct gain, which collects light through the windows; indirect gain, which stores thermal energy within the walls; and isolated gain, more commonly put to use in a solarium or sun room setup. By thinking about window placement, insulation, and even landscaping–trees can be the ultimate passive solar helpers, since they soak up solar in the hot summer, and let the sun through in the winter—it’s possible to help keep your home warm in the winter and cool in the summer.

Opt for solar hot water

You can also use solar power to heat the water for your showers, dishwasher, and laundry (though why aren’t you using cold water for that?) by installing a solar hot water system. If you live in a place where freezing temps aren’t a concern, look for a direct circulation system-this cycles water through the solar heater and into the home; otherwise, go for an indirect circulation system, which runs a freeze-proof fluid through the system to prevent icing. Both those active systems are generally more efficient than passive solar heaters, which don’t have the same pumps and controls but can be more dependable. No matter which system you choose, you’ll want to consider a (smaller) more traditional hot water heater for backup on days when the sun won’t come out or for showering during peak times.

Tap into the earth’s natural geo-energy

The terms “geothermal” and “ground source heat pump” are nearly interchangeable in casual conversation-but they shouldn’t be, since they’re not the same. Geothermal energy comes right from the ground-think hot springs, geysers, and volcanic areas—while ground source heat pumps use the relatively steady temperature of the Earth (as compared to the air) to heat and cool buildings. These heat pumps use as little as half as much electricity as traditional systems, and generally last between 25 and 50 years; while they are more expensive to install than other systems, you can expect the system to pay for itself in energy savings in less than 10 years.

Replace oil with biofuel

You can also heat your home using biofuels—nontoxic, biodegradable, and renewable power sources, like those made from animal and vegetable fats and oils or wood. If you’re using oil heat, have a technician take a look at your furnace and get the okay to switch to a blend of 20%-99% biodiesel; in most cases, you won’t need any additional parts or service to make the switch. Using a woodstove to heat your home is an age-old solution, but the more modern version is the pellet stove: The pellets of compressed sawdust take up less storage space than a wood pile, and burn with so few emissions that they aren’t required to get EPA certification. (One tip: if you’re going this route, find a local source for inexpensive pellets first.)

Harness the power of the wind

Wind energy is one of the cleanest forms of alternative energy available, and using it can cut your electricity bill by as much as 90 percent. Once you make sure your area is zoned to allow wind turbines, you’ll want to make sure you have enough space—the Department of Energy Efficiency and Renewable Energy suggests at least one acre of rural land—and a climate that affords a steady breeze. Run an energy audit on your home to determine what size turbine you’ll need; most houses require between 5 and 15 kilowatts to produce an average of 780 kilowatt hours every each month. And wind turbine systems aren’t cheap, so run the numbers to figure out if you’ll save enough to make the 20-year investment worth it.

Capture small-scale hydropower

Before you can use hydropower for residential energy, you’ll need one very important jumping-off point: running water on your property. If you are lucky enough to have a creek, stream, or river in your backyard, then a micro hydropower system may be a good alternative energy solution. By diverting a portion of the water through a wheel or turbine, you allow a shaft to spin; the spinning allows immediate results, like pumping water, or more indirect usage, like powering a generator. These calculations from the Department of Energy Efficiency and Renewable Energy can help you figure out if your water source will provide enough energy to significantly offset your electric bill.

Make a smart start

If you’re in the process of buying a home, it’s easier to make alternative energy work for you, by buying a property that comes with running water or room for wind turbines, for example. If you’re designing from the ground up, choose a roof that’s specially fitted for solar panels; place your house on the lot so it takes advantage of the sun; build with passive solar materials; and use daylighting technology by installing windows and doors in places that allow you to get the most out of natural light sources,and to go green.

Think smaller

If you can’t make the jump to powering your entire house with alternative energy, start by focusing on one room at a time. Or look even more closely at your life, and get small solar cells to charge your laptop, cell phone, iPod, and other small gadgets—every little bit helps!