Start with an energy audit

The first step to taking a whole-house energy efficiency approach is to find out which parts of your house or apartment use the most energy. A home energy audit will identify those areas, and through your own efforts, your local utility, or the assistance of a qualified professional, you can take cost-effective measures to reduce your energy costs and hence, your CO2 footprint.

"Retrofitting a home for energy efficiency will save you money, lots of money. However, it will require some effort on your part. You should start with an energy audit. First, do a simple visual inspection to locate the most obvious leaks – gaps between doors and frames, or large openings in the building envelope that let cold air in when the wind’s blowing and hot air out when the furnace is running. These can be sealed immediately and will often yield enormous benefits. Then, on a windy day, perform a search and destroy mission for smaller, less obvious leaks. Use incense, a smoke stick or simply your hand to detect drafts . . . . If this is more work than you’d like to undertake, or if you are feeling uncertain, you can always hire a qualified professional energy auditor to perform the inspection for you. You’ll find them in the business pages under 'Energy Conservation and Management Services' or 'Home Inspection.'"

References:

• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, p. 2 (June, 2005).
• The Mother Earth News Guide to Homes, Simple Energy Saving Strategies, p. 27, Summer, 2007.

Maintain and upgrade your heating and cooling equipment

More energy dollars go towards your heating and cooling system than any other system in your home. "Typically, 56% of your utility bill goes for heating and cooling. What’s more, heating and cooling systems in the United States together emit over a half billion tons of carbon dioxide into the atmosphere each year, adding to global warming. They also generate about 24% of the nation’s sulfur dioxide and 12% of the nitrogen oxides, the chief ingredients in acid rain."

"One of the most important things you can do to save energy is to regularly tune up your furnace. Up to 50% of the energy you use in your home goes to heating it. And a heating system can waste up to 50% of the energy it uses if it’s not operating efficiently. This can represent as much as 3,750 pounds of CO2 wastefully going into the air each year."

There are a number of things you can do to improve the efficiency and life of your heating system:

• Seal leaky ducts. Many duct systems are poorly insulated or not insulated properly. "Leaky ducts are notorious for decreasing the efficiency of warm-air furnaces and typically decrease their efficiencies by 20-30 percent." "Ducts that leak heated air into unheated spaces [such as attics or vented crawl spaces] can add hundreds of dollars a year to your heating and cooling bills. . . In addition, unconditioned air can be drawn into return ducts through unsealed joints. In the summer, hot attic air can be drawn in, increasing the load on the air conditioner. In the winter, your furnace will have to work longer to keep your house comfortable. Either way, your energy losses cost you money."
• Clean or replace air filters regularly. Dusty air filters block air from flowing freely through the filter, making fans have to work harder, in turn driving up energy consumption and raising bills.
• Clean warm-air registers and baseboard heaters, and make sure they are not blocked by furniture, carpeting or drapes.
• Insulate supply and return pipes. If you use a boiler to heat your home, be sure hot water and steam pipes that pass through unheated areas are wrapped with proper insulation.
• Install radiator reflectors. For boiler-heated homes, installing radiator reflectors avoids heat transfer from the radiator to the adjacent exterior wall, instead sending more of the heat into the room.

Other heating and cooling tips include:

• Adjust your thermostat appropriately. Set it as low as is comfortable in the winter (so-called "sweater" temperature when home, and "blanket" temperature at night or when away) and as high as is comfortable in the summer;
• Turn off exhaust fans. Turn off kitchen, bath and other exhaust fans sooner after you finish cooking or bathing;
• Passive heating and cooling. Keep draperies and shades on your south-facing windows open during the day (to take advantage of passive solar heating) and closed at night (to avoid heat loss) during the heating season, and keeping window coverings closed during the day to prevent solar gain during the cooling season.
• Get your appliances inspected. Have your heating and cooling system inspected by a technician on a regular basis to ensure it is operating at maximum efficiency.

In the case of room air conditioners, it is important to install a properly sized unit for the area being cooled. An air conditioner that is too big will actually perform less efficiently because room units are most effective when they run for relatively long periods of time instead of continually switching off and on. Longer run times allow air conditioners to maintain a more constant room temperature and remove excess humidity.

If your in the market for a new air conditioner, be sure to shop for an energy-efficient model. New, more energy-efficient air conditioners can save you up to 50% on your utility bill for cooling. Look for the ENERGY STAR and EnergyGuide labels.

Even if you are not in the market for a new air conditioner, there are several things you can do to increase your energy efficiency, save money and reduce your CO2 footprint:

• Use a whole-house fan to help cool your home. Whole-house fans pull cool air through the house and exhaust warm air through the attic. They're most efficient when the outside air is cooler than the inside.
• Don’t set your thermostat any lower (colder) than normal when you first turn on your air conditioner. A lower setting will not cool your home any faster and, if left untended, wiill result in excessive cooling and unnecessary expense.
• Use interior fans with window AC units. Use of an interior fan in conjunction with a window air conditioner can be effective at spreading cooled air through your home without greatly increasing your power use.
• Don’t place lamps, TVs, or other appliances that give off heat near the thermostat. The thermostat is designed to sense heat, and will run longer than necessary in such instances.
• Plant trees or shrubs to shade air conditioning units from the sun but not to block the airflow. When possible, place your room air conditioner on the north side of the house. "A unit operating in the shade uses as much as 10% less electricity than the same one operating in the sun."

Programmable thermostats can also help you save money and energy. "You can save as much as 10% a year on your heating and cooling bills by simply turning your thermostat back 10% to 15% for 8 hours. You can do this automatically without sacrificing comfort by installing an automatic setback or programmable thermostat."

Smart landscaping is yet another way to keep your home cool in the summer, warm in the winter and reduce your energy bills. "Carefully positioned trees can save up to 25% of a typical household’s energy used for heating and cooling. . . . [J]ust three trees, properly placed around the house, can save an average household between $100 and $250 in heating and cooling energy costs annually." Planting trees also helps to further reduce your carbon dioxide footprint, as a single tree will absorb roughly one ton of carbon dioxide over its lifetime.

If you are upgrading your heating and cooling system, select energy-efficient products. Look for the ENERGY STAR and EnergyGuide labels.

When upgrading, consider newer technologies, including geothermal heat pumps. Heat pumps are the most efficient form of electric heating in moderate climates, providing three times more heating than the equivalent amount of energy they consume in electricity. Heat pumps collect heat from the air, water or ground outside your home and concentrate it for use inside.

"In winter, a heat pump removes heat from the outside air and transfers it inside the home. In summer the processed is reversed. Heat pumps are an economical and energy-efficient way to provide space heating and cooling. . . . According to the EPA, geothermal heat pumps can save the average homeowner 30-70 percent in heating costs and 20-50 percent in cooling costs. This could save some homeowners up to $400 per year or more."

Geothermal systems should likewise be considered when upgrading your heating and cooling system. Geothermal systems provide the greatest energy savings in climates that have extreme heating and cooling loads and generate high energy bills. Geothermal systems are more expensive to install than other central heating options, but over time will save you money and help to reduce your CO2 footprint.

Solar power is yet another option that is rapidly gaining momentum in the United States. Incorporating a passive solar system, where the sun helps heat the house in cold weather and is shaded from the house in warm weather, into new or existing home design, can greatly reduce your heating and cooling costs. Unlike solar panels, which can require a large initial investment of money and time, designing a passive solar system can be surprisingly simple and inexpensive.

"In contrast to passive solar systems, active solar systems use supplemental electrical equipment, such as pumps and fans, to move heat around your home. In an active system, solar collectors harvest the sun’s energy to heat either liquid or air that is then pumped or blow through pipes or ducts to your living space. . . . Active solar heating systems are good choices in climates that have long heating seasons with high proportions of sunny days and above average fuel prices."

Rapid advances in solar-powered systems are revolutionizing the technology and increasing the ability of homeowners to generate "home-grown" electric power. "Installing clean, reliable, inflation-proof solar power is easier than ever, thanks to the invention of thin-film photovoltaic (PV) laminates that can be bonded directly onto metal roofing panels. Unlike crystalline PV material, there’s no need for obtrusive racks and heavy, expensive glass. Instead, unbreakable thin-film PV is produced using amorphous silicon, encapsulated in Teflon and other polymers."

References:

• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, pp. 10-11 (June, 2005)
• David Gershon, Low Carbon Diet: A 30 Day Program to Lose 5000 Pounds, pp. 26; 33 (2006)
• Rocky Mountain Institute, Home Energy Briefs, #4 Space Heating (2004), found at: http://www.rmi.org/
• The Mother Earth News Guide to Homes, Go Solar, You Can Do It!, Summer, 2007, pp. 1; 34.

Make your hot water heater more efficient

After household heating and cooling, water heating is the largest energy user in your home, representing over 13% of your annual energy bill, and a significant contributor to household CO2 emissions. "If your water heater is more than 10 years old it is likely running at less than 50 percent efficiency—wasting energy and money—but most people don’t replace their water heater until it fails. Upgrading to a new, more efficient model will lower not only your monthly expenses, but also your contribution to air pollution and global warming." Even if you don’t plan on buying a new water heater in the near future, there are a number of measures you can take now to save money, and energy, with your existing system.

The biggest savings can be achieved by simply using less hot water. Not only does it save you money while reducing your CO2 footprint, cutting down on water conserves our water supplies. "A family of four each showering five minutes a day can use about 700 gallons per week—a three-year drinking water supply for one person! Water-conserving showerheads and faucet aerators can cut hot water use in half. That family of four can save 14,000 gallons of water a year and the energy required to heat it."

If your water heater was installed before 2004, consider installing an insulating jacket on your existing water heater. Insulation jackets are inexpensive and easy to install, and are particularly effective if your water heater is located in an unheated space such as a basement. "The insulating jacket will reduce standby heat loss—heat lost through the walls of the tank—by 25–40%, saving 4–9% on your water heating bills." Many newer water heaters already come well insulated, making it unnecessary to install an insulating jacket in terms of any additional economic benefit. In fact, some manufacturers recommend against installing insulating jackets on their energy-efficient models. Always follow the manufacturer’s recommendations, and be careful not to restrict air inlets when insulating conventional gas or oil-fired water heaters.

Insulating your hot water pipes will also reduce heat loss and save you money. Not only does it reduce losses as hot water flows from your water heater to your faucet, insulating your hot water pipes also reduces standby losses when the tap is turned off and then back on in within an hour or so. "A great deal of energy and water is wasted waiting for the hot water to reach the tap. Even when pipes are insulated, the water in the pipes will eventually cool, but it stays warmer much longer than it would if the pipes weren’t insulated."

Turn down the thermostat on your hot water heater. A lot of energy, and money, is wasted simply by setting your thermostat too high on your water heater. "For most households, 120°F water is fine (about midway between the 'low' and 'medium' setting). Each 10°F reduction in water temperature will generally save 3–5% on your water heating costs. When you are going away on vacation, you can turn the thermostat down to the lowest possible setting, or turn the water heater off altogether for additional savings. With a gas water heater, make sure you know how to relight the pilot if you’re going to turn it off while away."

If you are in the market for a new hot water heater, there are several energy-efficient models that you can choose from to meet your needs and budget. They include:

• Storage water heaters – the most common type on the market. They maintain a large tank of water at a set temperature, and are best suited for larger households that use a lot of hot water. "Storage water heaters have become more efficient over the years, but some energy is still wasted when the hot water is not being used (known as standby energy loss)."
• Tankless water heaters – also known as on-demand or instantaneous heaters. They use energy only when hot water is needed, resulting in less standby energy loss than storage heaters. "They tend to have a higher up-front cost, but are less expensive to operate in the long term due to their higher efficiency." "Researchers have found savings can be as much as 34% compared with a standard electric storage tank water heater."
• Solar water heaters – they transfer heat from the sun into a conventional storage tank. "They have higher up-front costs than conventional water heaters but much lower operating costs, and can pay for themselves within 4 to 10 years under favorable conditions." Heating with the sun has the added advantage of helping to reduce your carbon dioxide footprint. "Solar water heaters avoid the harmful greenhouse gas emissions associated with electricity production. During a 20-year period, one solar water heater can avoid over 50 tons of carbon dioxide emissions."

Other tips for conserving energy include:

• Repairing leaky faucets promptly;
• Taking showers instead of baths - bathing uses the most hot water in the average household – a typical bath uses 15-25 gallons of hot water, while a 5-minute shower uses less than 10 gallons;
• Installing heat traps on the hot and cold pipes at the water heater to prevent heat loss – heat traps are essentially one-way valves that prevent unwanted hot water from flowing out of the tank and water that may be sitting in the pipes from flowing back into the water heater; and
• Draining some water (about a quart) from your water tank several times a year to remove sediment that can impede heat transfer and lower the efficiency of your heater.

References:

• Energy Information Administration, Residential Energy Consumption Survey, 2001, found at: http://www.eia.doe.gov/emeu/recs/
• Union of Concerned Scientists, Hot Water with Less Worry, (October, 2006), found at: http://www.ucsusa.org/publications/greentips/hot-water-with-less-worry.html
• American Council for an Energy Efficient Economy, Water Heating, found at: https://www.aceee.org/consumerguide/topwater.htm
• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, p. 17 (June, 2005)

Replace inefficient bulbs and fixtures with energy efficient lights

Lighting is the third largest energy user in your home, representing approximately 10% of your annual energy bill. "Making improvements to your lighting is one of the fastest ways to cut your energy bills. . . . Using new lighting technologies can reduce lighting energy use in your home by 50% to 75%. Advances in lighting controls offer further energy savings by reducing the amount of time lights are on but not being used."

"Lighting is responsible for using about a fourth of all electricity consumed in the United States, of which 20 percent goes to extra air conditioning to remove unwanted heat (from lighting). In fact, more than 90 percent of the energy consumed by a standard incandescent bulb is given off as heat, while only 10 percent is converted into light!"

• "If every household replaced just three 60-watt incandescent bulbs with CF bulbs, the pollution savings would be like taking 3.5 million cars off the road!"


• "Consumers put off by the slightly higher initial cost of CFLs should note that they last up to thirteen times as long (10,000-12,000 hours) as standard incandescents (750-1,500 hours), and use about one-quarter of the electricity. Thus, one CFL can also eliminate the need to produce, install, remove, and dispose of over a dozen standard incandescent bulbs. To top it off, each CFL you install can save you over $50 in electricity costs over the lifetime of that bulb. For example, if you replaced five 75-watt bulbs in your house with CFLs, you could save over $250 over eight years!"


• "Using compact fluorescent light bulbs instead of incandescent bulbs in rooms where lights are on for at least 4 hours per day saves 100 pounds of CO2 annually per bulb."


• If you are shopping for new light fixtures, look for dedicated compact fluorescent fixtures with built-in ballasts that use pin-based replacement bulbs. Replacement bulbs are cheaper and smaller because the ballast is a separate part of the fixture, and they last even longer – up to 40,000 hours. "If all the households in the United States replaced five 100-watt fixtures with 23-watt CFL fixtures, the electricity saved would power more than three cities the size of New York City, day in and day out."


• Modern compact fluorescent bulbs do contain small amounts (about 4 milligrams) of mercury, raising environmental concerns if not properly disposed. Yet using a CFL actually creates a net reduction in the amount of mercury released over its lifetime. This is because the largest source of mercury in the air is coal-burning power plants. Since use of an efficient CFL bulb instead of an incandescent bulb requires less energy from coal-fired power plants, it reduces the amount of mercury released directly into the atmosphere by coal-burning power plants - by up to 36 percent. If the CFL is recycled at the end of its life, the amount of mercury released is reduced even further - by 76 percent

Light-emitting diode (LED) technology has even more potential for energy savings and longevity. LEDs are already standard usage in products such as headlamps, cell phones, bicycle lights, and Christmas lights. "Modern LEDs have the potential to last ten times longer than CFLs, depending on the type of application, the type of LED, and the product in which they’re used – some LED table lamps use only 5 watts."

Halogen lamps, while less efficient that LEDs or CFLs, are still up to 50% more efficient than a standard incandescent lamp. Halogen bulbs cost more than standard incandescents but last twice as long, making them a cost-effective investment over time.

Additional tips for energy-efficient lighting include turning off lights in any room you’re not using, installing timers, photo cells or occupancy sensors to reduce the amount of time your lights are on, using task lighting instead of lighting an entire room, and taking advantage of natural daylight to further reduce your energy use and therefore your carbon dioxide footprint.

Another important point is before installing a CFL in a dimmer-controlled fixture, be sure it is designed for that purpose. Additionally, turning a CFL on and off frequently can shorten its life. "To take full advantage of the energy savings and long life of ENERGY STAR qualified CFLs, it is best to use them in light fixtures you use the most and are on for at least 15 minutes at a time. Good locations include outdoor light fixtures, indoor fixtures in the living room, family room, kitchen, bedroom, recreation room, etc. This is not to say you should leave your lights on all day if you use ENERGY STAR qualified CFLs. It is still a good habit to turn the lights off when you leave the room for an extended period of time."

References:

• Residential Energy Consumption Survey, 2001, found at: http://www.eia.doe.gov/emeu/recs/
• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, p. 20 (June, 2005).
• Rocky Mountain Institute, Home Energy Briefs, #2 Lighting, (2004), found at http://www.rmi.org/
• Environmental Defense, How to Pick a Better Bulb, found at: http://www.fightglobalwarming.com/page.cfm?tagID=608
• Energy Star, CFL FAQs, found at: http://www.energystar.gov/index.cfm?c=cfls.pr_cfls

Seal air leaks

"Heat naturally flows from warmer spaces to cooler ones until the temperatures both in and between the two spaces are equal. Inside the home, warm air rises and leaks out the attic and roof while drawing cold air in through the basement. Your home’s shell (walls, windows, doors, foundation, roof, attic, etc.) determines its rate of heat loss, and leaky shells can be responsible for 25-40 percent of the load on your heating system. You can prevent this heat loss by implementing passive heating measures such as improving insulation, sealing air leaks, and replacing or reglazing your windows to minimize heat transfer."

"Air leaks around doors, windows, and electrical outlets; through the fireplace; in basements (between the foundation and the frame); and especially in attics lose as much heat, in the typical home, as leaving an average-size window open all winter long. The extra heating fuel required to compensate for these energy leaks represents up to 800 pounds of CO2 emissions annually."

Making sure your home is properly insulated is one of the easiest and most cost-effective ways to reduce energy waste, save money and reduce your carbon dioxide footprint. "You can increase the comfort of your home while reducing your heating and cooling needs by up to 30% by investing just a few hundred dollars in proper insulation and sealing air leaks."

• Making sure your home meets recommended levels of insulation for your region should start with checking areas where significant air leakage, and hence unnecessary cost, can occur. These include your attic, ceilings, exterior and basement walls, floors and crawl spaces.


• Insulation is measured in R-values, a measure of a material’s resistance to heat transfer by conduction (conduction refers to the transfer of heat through a solid object, from its warmer side to its cooler side). The higher the R-value, the better your floors, walls and roof will resist the transfer of heat.


• The U.S. Department of Energy (DOE) recommends ranges of R-values based on local heating and cooling costs and climate conditions in different areas of the nation. The DOE produces maps and charts detailing these recommendations, found at http://www1.eere.energy.gov/consumer/tips/insulation.html. The DOE also has a zip code insulation calculator for insulation recommendations tailored to your home, found at http://www.ornl.gov/~roofs/Zip/ZipHome.html.

Insulation can be made from a variety of materials. Four main types of insulation include:

• Rolls and batts — or blankets — flexible products made from mineral fibers, such as fiberglass and rock wool. They are available in widths suited to standard spacings of wall studs and attic or floor joists: 2x4 walls can hold R-13 or R-15 batts; 2x6 walls can have R-19 or R-21 products.
• Loose-fill insulation — usually made of fiberglass, rock wool, or cellulose — comes in shreds, granules, or nodules. These small particles are blown into spaces using special pneumatic equipment. The blown-in material conforms readily to building cavities and attics. Loose-fill insulation is well suited for places where it is difficult to install other types of insulation.
• Rigid foam insulation — typically more expensive than fiber insulation. Rigid foam insulation is very effective in buildings with space limitations and where higher R-values are needed. Foam insulation R-values range from R-4 to R-6.5 per inch of thickness, which is up to 2 times greater than most other insulating materials of the same thickness.
• Foam-in-place insulation — can be blown into walls to reduce air leakage.

Adding insulation to your attic is one of the easiest and most cost-effective ways to make your home more comfortable year-round. "To find out if you have enough attic insulation, measure the thickness of the insulation. If it is less than R-22 (7 inches of fiber glass or rock wool or 6 inches of cellulose), you could probably benefit by adding more. Most U.S. homes should have between R-22 and R-49 insulation in the attic."

New products on today’s market provide both insulation and structural support, and should be considered for new home construction or additions. "Structural insulated panels, known as SIPS, and masonry products like insulating concrete forms are among these."

An old building technique that is regaining popularity is straw bale construction. Straw bale homes are constructed by stacking rectangular bales of straw and covering them with a plaster shell. "Straw bale walls are at least twice efficient as those from conventional stick-frame construction and will save you money on heating and cooling bills."

According to the DOE, only 20% of homes built before 1980 are well insulated. Accordingly, adding insulation may be the best way to improve your home’s energy efficiency. It can create a more uniform temperature year round, muffle sound from outside, save on your energy bills and help to further reduce your CO2 footprint.

References:

• Rocky Mountain Institute, Home Energy Briefs, #4 Space Heating (2004), found at http://www.rmi.org/
• David Gershon, Low Carbon Diet: A 30 Day Program to Lose 5000 Pounds, p. 25 (2006)
• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, pp. 4-6 (June, 2005)
• Magwood, Chris; Mack, Peter; and Therrien, Tina, Expert Advice on Straw Bale Building, The Mother Earth News Guide to Homes, p. 44 (Summer, 2007)

Replace older appliances with energy-efficient models

Appliances such as your refrigerator, clothes washer and dryer, dishwasher and electronics (TV, computer, audio and video systems, etc.) account for about 20% of your household’s annual energy bill. "Together, these items account for nearly eight tons of heat-trapping emissions per household per year."

When shopping for a new appliance, look for the ENERGY STAR label. ENERGY STAR products usually exceed minimum federal standards by a substantial amount. The ENERGY STAR label should not be confused with the bright yellow and black EnergyGuide label – the federal government requires this label to be displayed on most new appliances, and the label provides information about the energy efficiency of a particular appliance. Although these labels will not tell you which appliance is the most efficient, they will tell you the annual energy consumption and operating cost for each appliance so you can compare them yourself. The American Council for an Energy-Efficient Economy lists the energy performance of top-rated energy-saving appliances on its web site: http://www.aceee.org/.

Replacing older appliances with new, energy-efficient models can provide substantial reductions in both your energy costs and your CO2 footprint. "Replacing a dishwasher manufactured before 1994 with an ENERGY STAR dishwasher can save you more than $25 a year in electric or natural gas costs." A dishwasher with an ENERGY STAR label uses up to 25% less energy than required by federal standards.

"The EnergyGuide label on new refrigerators will tell you how much electricity in kilowatt-hours (kWh) a particular model uses in one year. The smaller the number, the less energy the refrigerator uses and the less it will cost you to operate. In addition to the EnergyGuide label, don’t forget to look for the ENERGY STAR label. A new refrigerator with an ENERGY STAR label uses at least 15% less energy than required by current federal standards and 40% less energy than the conventional models sold in 2001."

Other refrigerator tips include:

• Shopping for a refrigerator with automatic moisture control. Such models prevent moisture accumulation without the need for an "anti-sweat" heater, which will consume "5% to 10% more energy than models without this feature."
• Not setting your refrigerator or freezer too cold. "Recommended temperatures are 37º to 40ºF for the fresh food compartment of the refrigerator and 5ºF for the freezer section. If you have a separate freezer for long-term storage, it should be kept at 0ºF."
• Regularly defrosting manual-defrost refrigerators and freezers Frost buildup decreases the energy efficiency of the unit.
• Ensuring your refrigerator door seals are airtight.
• Covering liquids and wrapping foods to prevent the release of moisture which makes the compressor work harder.
• Vacuuming the refrigerator’s condenser coils once a year (unless you have a no-clean condenser model) to save on energy.

Substantial cost and energy savings can also be realized in the area of a home office and home electronics. An increasing number of people work from home on a regular or periodic basis. Working from home greatly reduces the CO2 footprint caused by driving or commuting to work. However, it could cause a substantial increase in your home energy bills unless you invest in or use energy-saving office equipment.

"ENERGY STAR office equipment is widely available: it provides users with dramatic savings, as much as 90% savings for some products. Overall, ENERGY STAR office products use about half the electricity of standard equipment. Along with saving energy directly, this equipment can reduce air-conditioning loads, noise from fans and transformers, and electromagnetic field emissions from monitors."

A substantial amount of energy, and hence cost, is wasted by leaving appliances on when not in use. "Common misconceptions sometimes account for the failure to turn off equipment. Many people believe that equipment lasts longer if it is never turned off. This incorrect perception carries over from the days of older mainframe computers. . . . There is a common misconception that screen savers reduce energy use by monitor; they do not. Automatic switching to sleep mode or manually turning monitors off is always the better energy-saving strategy."

Wasting power by leaving home electronics on when not using them is costly and needlessly increases your carbon dioxide footprint. In addition, many appliances continue to draw power even when they are switched off; so-called "phantom" loads, which can be found in items such as VCRs, TVs, stereos, computers, and kitchen appliances.

"In the average home, 75% of the electricity used to power home electronics is consumed while the products are turned off." "Add that all up, and it equals the annual output of 17 power plants, the government says." A good solution to this problem is plugging appliances into a power strip and using the switch on the power strip to cut all power to the appliance.

If you choose to leave home electronics on for periods of time, products that idle in a reduced power mode are preferable to those that do not, but even those products can waste significant amounts of energy. "Products that idle in what the industry calls low-power mode, or lopomo, consumed about 10 percent of total electricity in California homes, according to a 2002 study prepared for the California Energy Commission by the Lawrence Berkeley National Laboratory."

References:

• Energy Information Administration, Residential Energy Consumption Survey, 2001, found at: http://www.eia.doe.gov/emeu/recs/
• Environmental Defense, Fight Global Warming, Save Energy and Money at Home, found at: http://www.fightglobalwarming.com/page.cfm?tagID=267
• Larry Magid, The New York Times, Putting Energy Hogs in the Home on a Strict Low-Power Diet, June 14, 2007, found at: http://www.nytimes.com/2007/06/14/technology/14basics.html?ex=1339473600&en=09f3f4ee316d0508&ei=5090

Install energy-efficient windows

Almost half of all homes in the U.S. have inefficient, single-pane windows. Inefficient windows can account for up to 25% of your heating bill in the winter, and can make your air conditioner work up to three times harder in the summer. Although high performance windows may cost more initially, they save you money in the long run. In addition, they increase the value of your home.

If you are shopping for new windows, look for the National Fenestration Rating Council (NFRC) label. The NFRC provides information for windows and skylights similar to fuel economy ratings on new cars, allowing you to compare the energy ratings of various windows. An NFRC label means the window’s performance is certified.

Window rating systems help you evaluate three main factors that affect the energy efficiency of windows. "The first is heat flow through the glass and frame, which is generated by the temperature difference between the inside of your home and the outside environment. . . . Heat transferred through a window is expressed with U-values; the lower the U-value, the better. The resistance to heat flow is expressed as an R-value. . . In general, the higher the R-value, the better the insulation."

Higher R-values are achieved with multiple panes of glass. Double-pane windows insulate almost twice as well as single-pane windows. In a double-pane window, the air space between the panes of glass provides insulation, reducing the amount of hot or cold air being conducted from one side of the window to the other.

The second major factor affecting a window’s energy efficiency is solar gain, also called the solar heat gain coefficient (SHGC). "Put simply, the SHGC measures how much of the sun’s energy (both visible and near-infrared light) striking the window transmits as heat into the room. . . . The SHGC also measures how much solar heat passes through the frame, not just the glass."

"The third factor that affects a window’s energy efficiency is air leakage. This is the air that flows through cracks between the sash and the frame, or at the point where the window connects to the wall. The lower the leakage value, the better."

Low-emissivity, or low-e, coatings have revolutionized window technology over the last three decades. "Thin, transparent coatings of silver or tin oxide permit visible light to pass through, but they effectively reflect infrared heat radiation back into the room." Low-e glass keep heat inside in winter and outside in summer. They also reflect damaging ultraviolet light, helping to protect interior furnishings from fading.

Some energy-efficient windows are filled with low-conductivity gas, such as argon, krypton, and yes, even CO2. These lower conductivity gases insulate better than regular air.

Tinted glass and tinted window films can further help to reduce solar gain by reflecting light back outside. Tinted glass has its limitations, however, as it tends to absorb some heat and reduces overall visibility, but may be an effective choice for certain applications or in certain areas.

Another factor to consider when purchasing windows is edge spacers. Edge spacers keep the window’s glass panes the correct distance apart. Traditionally, edge spacers were made of aluminum, a highly conductive material. In more recent years edge spacers made of foam, fiberglass and vinyl have been developed. These materials further reduce heat flow and prevent condensation.

If you are not ready to replace your existing windows, there are a number of inexpensive measures you can take to improve their performance:

• Weatherize windows in winter. Use a heavy-duty, clear plastic sheet, either on a frame, or taped to the inside of your window frames during cold weather months.
• Install tight-fitting insulating shades on drafty windows.
• Passive solar heating and cooling. Use shades and curtains to block heat loss through windows in cold weather and to block passive solar heat in the summer.
• Install exterior storm windows – they can reduce winter heat loss by up to 50%. Low-e storm windows can save even more energy.
• Install awnings on south- and west-facing windows to block heat from the sun in warmer months.

References:

• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, p. 18 (June, 2005).
• Pahl, Greg, High Performance Windows, The Mother Earth News Guide to Homes, p. 69 (Summer, 2007)
• American Council for an Energy Efficient Economy, Consumer Guide to Savings: New Windows, found at: http://www.aceee.org/consumerguide/windows.htm

Switch to "green" power

More and more states are adopting renewable portfolio standards (RPS), also known as renewable electricity standards (RES). These standards require utilities to provide increasing amounts of electricity to consumers from renewable energy resources, like wind, solar and biomass. Congress is now considering passage of a national RPS, and it is only a matter of time before our energy policy shifts from over-reliance on coal, and the harmful effects of CO2 and other toxic air emissions, to investments that increase energy efficiency in homes, businesses and industry, and that develop the full potential of renewable energy resources, which produce little or no emissions and which, unlike fossil fuels, are limitless in supply.

At the same time, there are a number of options for using renewable energy at home. Some options, like generating electricity from small-scale wind turbines or solar photovoltaic panels, require larger up-front investments, but can result in large energy savings over time. Others options are relatively inexpensive and can achieve more immediate savings.

Recent advances in residential wind turbines make them more affordable and easier to use than ever before. "The proliferation of net metering laws [laws that allow homeowners to sell extra energy generated by wind and solar systems back to the utility], in about 40 states, as well as a growing number of state residential wind incentive programs, has given a strong boost to the small-scale wind turbine industry. . . . Many in the small-scale wind turbine industry think residential wind power is about to enter suburbia with simpler, less expensive systems that perform more like household appliances than complicated renewable energy systems. And the potential is enormous; it’s estimated there are at least 15 million homes with the resources necessary to make a wind installation effective."

Whether it makes sense to install a wind turbine in your back yard depends on variables such as your lot size, zoning restrictions, wind speeds in your area, the cost and amount of electricity you use, whether your utility offers net metering, and the availability of state rebates and incentives.

Solar photovoltaic (PV) systems are another option for using renewable energy to support your household electricity needs. The initial investment, while likely to be less expensive than small-scale wind, is still considerable, and may not be cost-effective in all settings, at least not at this time. "The most important factors for making solar an attractive investment include high electric rates, net-metering policies, financial incentives and good sunlight." The good news is that recent advances in technology are making solar PV systems more affordable and easier to install, and these trends are likely to continue.

Passive solar design is another renewable energy strategy, the costs for which are largely in your control depending on your budget. "The best aspect of solar design is that if you’re building or remodeling a home, you can incorporate it at little or no extra expense. With oil and natural gas prices rising, and power blackouts becoming more common, it now makes more sense than ever to take advantage of natural heating and cooling rather than depending on fossil fuels."

"A new home provides the best opportunity for designing and orienting the home to take advantage of the sun’s rays. A well-oriented home admits low-angle winter sun to reduce heating bills and rejects overhead summer sun to reduce cooling bills."

Another use of solar power is for heating water. "If you heat water with electricity, have high electric rates, and have an unshaded, south-facing location (such as a roof) on your property, consider installing a solar water heater. . . . More than 1.5 million homes and businesses in the United States have invested in solar water heating systems, and surveys indicate over 94% of these customers consider the systems a good investment. Solar water heaters are also good for the environment. Solar water heaters avoid the harmful greenhouse gas emissions associated with electricity production. During a 20-year period, one solar water heater can avoid over 50 tons of carbon dioxide emissions."

Buying green power from your utility is yet another alternative for supporting renewable energy without having to invest in equipment or ongoing maintenance. Virtually all utilities offer this option, including Indianapolis Power and Light (IPL), Duke Energy, and rural electric cooperatives that serve other portions of Indiana. Presently green power is purchased at a premium, but the additional cost is relatively small. IPL purchases its green power from a Minnesota wind farm and Indiana landfill gas generation plants. "At this premium, a typical residential customer using 1000 kilowatt-hours in a month and enrolled at the 100% level would pay an additional $1.91 on their IPL electric bill."

If your utility doesn’t offer green power purchasing options, consider buying "carbon credits." A number of organizations sell carbon credits, sometimes called renewable energy certificates, or RECs. With these programs, you can calculate how much CO2 you are responsible for and purchase credits to offset that amount. You can access these programs online by doing a search for "carbon offsets" or "carbon credits."

Carbon offsets are a "handy mechanism that allows us to convert our units of personal carbon emissions into dollars for wind farms, reforestation projects and other conscience-cleansing pursuits. The theory is that such investments cancel out the environmental harm we do by burning gasoline and living in warm, gadget-laden homes."

Even if you have actively taken steps to reduce your carbon dioxide footprint, through offsets you can reduce your footprint further, all the way to zero. “When you buy offsets, you essentially pay someone to reduce or remove global warming pollution in your name. For example, when you buy 10 tons of carbon offsets, the seller guarantees that 10 fewer tons of global warming pollution go into the atmosphere. While the pollution you produce yourself is the same, you get the credit for that 10-ton reduction."

Most of the offset companies on the market use third-party certification to provide accountability, so that when you buy carbon credits, you can be assured that they are paying for the renewable resources they are claiming to support, and eliminating the promised amount of greenhouse gas. "The certifying agencies evaluate offset projects on factors such as 'additionality' (whether the greenhouse-gas reduction would happen anyway) and 'double counting' (more than one stakeholder takes credit for the same project). But they don’t weigh in on which type of offset is best."

"Ultimately, the key to reducing carbon dioxide is to shift from using fossil fuels to using renewable energy (wind, solar, small hydro, biomass). This form of energy reduces not only CO2 emissions but also pollutants in the air. It may not be practical to set up a renewable energy source in your own home but you can purchase 'green power' from local electrical utility companies. While this mode of energy is currently a little more expensive . . . you can easily make up for the costs with the energy efficiency cost savings from other actions . . . This action is one of the most effortless ways to reduce your CO2 emissions."
References:

• Greg Pahl, Mother Earth News, New and Imporved Wind Power, June/July, 2007, p. 36.
• Andy Black, The Mother Earth News Guide to Homes, You Can Afford Solar Power, Summer, 2007, p. 39.
• Clarke Snell, The Mother Earth News Guide to Homes, Go Solar and Save Big!, Summer, 2007, p. 62.
• U.S. Department of Energy, Energy Efficiency and Renewable Energy: Energy Saver$: Tips on Saving Energy & Money at Home, pp. 17; 32 (June, 2005)
• IPL, Green Power Option for Renewable Energy, found at: http://www.iplpower.com/ipl/index?page=IPLGeneral&Menu=01000000&DocID=0205016c986701096a4e9803007c1f
• The Mother Earth News Guide to Homes, Vote with Your Dollars: Opt for Green Energy, p. 12 (Summer, 2007)
• Kimberly Lisagor, Mother Jones, Paying for My Hot Air, May/June, 2007, pp. 74-75. Environmental Defense, Fight Global Warming: Neutralize Your Pollution, found at: http://www.fightglobalwarming.com/page.cfm?tagID=270
• David Gershon, Low Carbon Diet: A 30 Day Program to Lose 5000 Pounds, p. 29 (2006)