Alternative energy sources
Powering and heating your home with clean energy sources sounds like a no-brainer when it comes to going green, but deciding which kind of fuel is right for you isn't as simple. Solar power? Wind power? Hydropower? Geothermal power?--active or passive? It's overwhelming--and it's enough to stop you before you even get started.
Green energy alternatives
We've taken the guesswork out: the following pages offer comprehensive breakdowns of the different types of energy and notes on what you should consider before investing in one, so it's easy to figure out which best fits your needs and lifestyle. Change the energy source in your home, or--if you're buying or building--learn what to look for during the planning and construction process. Not in a position to green your whole house? You can start with smaller changes, like powering just one room.
Alternative energy in the home
But the first thing you should do before switching to green power sources is simple: cut back on the electricity you use now by increasing your energy efficiency. In addition to trimming your electric bills and carbon output, needing less energy will make providing your own that much easier. Since most of us are already connected to the traditional power grid, the logical (and easiest) first step is to make the energy we're using go as far as possible. That way, when you start incorporating the use of more alternative energy into your home, you'll need less of it.
Top Green Alternative Energy Tips
- 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? Check this chart of Green Power Networks to see your local providers.
- 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 can be stored for later or used immediately to provide heat or electricity-or to supplement a traditional heating or electrical system. You can use a grid tie to go off-grid entirely, or you can stay on the regular power grid even if you have solar panels, so that the grid acts as your backup and provides power at night or on cloudy days. The good news is prices have fallen a lot over the past few years and solar power is now very affordable in many regions, often cutting your monthly power bill. 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.
- 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. Ground source heat pumps are a way to reduce electricity use for heating and cooling, so that it's easier to go 100% renewable. These heat pumps use as little as a quarter to a half as much electricity as traditional systems, and generally last between 25 and 50 years; you can expect the system to pay for itself in energy savings in less than 10 years.
- Replace fossil fuels with biomass/biofuels
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. 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
If you're looking for a bigger clean energy project and 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 selecting a well insulated and energy-efficient home that makes good use of passive solar, because that means you need less electricity to be clean, for example. It also means you need fewer solar panels and that your bills will be smaller. 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.
Interesting Facts & Numbers about Alternative Energy
- 600 percent: The highest average efficiency of a ground source heat pump in the winter, compared to 250 percent for air-source pumps.
- 12: Percentage of the average household electricity bill that goes toward lighting alone.
- 7: Lowest wind speed (in miles per hour) from which it's efficient to harness wind power.
- 280,475: Number of photovoltaic cells shipped domestically in 2007.
- Solar power: use has increased by 53x in the last 9 years.
- Wind power: use has increased by 6.6x in the last 9 years
- 21 percent: Energy Information Administration's estimate of how much world electricity was generated by renewable energy. They project that it will rise to 25 percent by 2040.
Alternative Energy Tech: Net Metering, Biofuels & More
Renewable energy sources are often a great alternative to traditional power, but cloudy days, droughts, and still air can all get in the way of even the best-laid plans for solar, water, or wind power. If you're worried about relying entirely on the power you can capture from Mother Nature, there's another option: hook your system into the established energy grid (with the permission of your town's electricity provider) and use it as a backup. Often, they'll put you on a net-metering plan, which means the company keeps track of the energy you make and subtracts it from what they provide, so you only pay the difference. In months where you make more than you use, they'll send you a check for the balance.