Using solar or wind power to create electricity for your own use is an exciting idea. But unless the cost of installing the system provides a reasonable return on investment (ROI), it doesn't make financial sense.
Quite often you will hear this is discussed in terms of the system "payback". The payback period of a renewable energy system is the amount of time it takes for you to recoup your initial expenditure through energy savings. The payback period is important, but it is only one factor to consider when determining if renewable energy is a sound long-term investment. But, since this is not an in-depth discussion on system ROI, we will use payback to illustrate the importance of energy efficiency in keeping the upfront cost of your renewable energy system affordable.
The basic rule is that for every $1 you spend making your structure more energy efficient, you will save $3 to $5 on the cost of your renewable energy system. Which of course also means that the payback period for your RE system will be quite a bit shorter. Your initial investment on energy saving measures will also be lower, and the payback period on those energy saving measures less , than for solar or wind systems. This makes it easy to see that spending money on energy efficiency measures should come first, reducing your electricity bill by generating your own power second.
Energy efficiency measures can be relatively expensive - replacing old windows or an inefficient heating system, more moderate - adding insulation or upgrading to Energy Star appliances, or inexpensive to free - lowering your thermostat setting, replacing incandescent light bulbs with compact fluorescents, or decreasing your hot water temperature setting. Whatever you choose to do, it will be worth the time, expense and effort, particularly if you decide to proceed with a solar PV or wind power system.
Making Your Home Energy Efficient
In the United States, about 10% of the electricity consumed is for lighting. Because lighting is relatively simple and inexpensive when compared to many other items in our life that consume electricity, it's a great place to start eliminating waste.
Compact fluorescent lamps (CFLs) use 65 to 75% less energy and last 8 to 15 times longer than a standard light bulb, while providing the same amount of light. Though more expensive than incandescent bulbs, by replacing a 100 watt incandescent with a 32 watt CFL you will save $30 or more in electricity costs over the lifetime of that bulb (about 10,000 hours). When you consider how many light bulbs you have in your home, this can add up to significant savings. According to a December 19, 2007, US News and World article “A household that invested $90 in changing 30 fixtures to CFLs would save $440 to $1,500 over the five-year life of the bulbs, depending on your cost of electricity. Look at your utility bill and imagine a 12% discount to estimate the savings.”
CFL technology has improved in the last few years, and you'll find there are now CFLs that will fit in most light fixtures; there are even dimmable CFLs!. Which makes replacing as many of your standard light bulbs with CFLs a smart thing to do.
Another benefit of changing to CFLs is a potential reduction in the power consumed for air conditioning. CFLs produce substantially less heat than incandescent bulbs, so in hot climates, this heat reduction can mean savings. Of course the overall cost savings will depend on the climate, and will be offset in part or completely by an increase in heating energy demand in the winter.
Tubular Skylights capture direct and ambient light from your rooftop and direct it down through a highly reflective tube, to be diffused at the ceiling level. Tubular skylights provide exceptional daylight illumination, even on cloudy days and in early morning or late afternoon when the sun is low in the sky. Frequently tubular skylights are used in hallways and closets to illuminate the space without having to flip a switch. In some installations this all natural lighting can provide as much illumination as a 100-Watt incandescent light bulb.
In most homes, refrigeration is the biggest consumer of electricity after electric heating or cooling systems. Even a refrigerator manufactured as recently as 1990 is likely an power hog. And just because your refrigerator has an Energy Star label doesn't mean it's efficient. It only means that its efficiency exceeds the federally mandated efficiency standard by at least 15%.
Investigate online at www.energystar.gov to learn how much power your refrigerator consumes. If it has a low Energy Star rating, consider replacing it with a newer model with a high rating. You can also research new refrigerators by brand, type and size and sort by energy efficiency, to save you time in the store. When in the store, consult the yellow EnergyGuide tags attached to all new refrigerators (and many other appliances). EnergyGuide tags offer information about annual energy consumption and provides a comparison with similar models. For maximum energy savings, select the model that's a leader in efficiency in its class.
Heating and Cooling
The biggest consumer of power in most homes are the furnace and air conditioner. Installing a programmable thermostat is simple and affordable, and you will quickly recoup your small investment by running your heating and cooling systems less.
Sealing air leaks and adding insulation is another way to reduce your home heating and cooling costs. Depending on where and how much work you do, you can save as much as 10%. Plenty of information about insulating is available online, or talk to your local home improvement store to get recommendations for your area.
Blinds and Drapes
Even with high efficiency windows., keeping blinds and drapes closed in south and west windows on hot, sunny days can decrease the heat load in your home, effectively reducing how much power is used for cooling.
In winter, a ceiling fan set on low can help circulate warm air trapped in high ceiling areas. In the summer, a ceiling fan will keep air moving, which not only feels cooler than stagnant air, but will also help mix trapped hot air with any that is cooled mechanically, balancing the temperature throughout your home.
Attic fans cool hot attics by drawing cooler outside air in through attic vents (soffit and gable) and pushing hot air to the outside. However, if your attic has blocked soffit vents and is not well-sealed from the rest of the house, attic fans will suck cool conditioned air up out of the house and into the attic. This will use more energy and make your air conditioner work harder, which will increase your summer utility bill. To prevent this be sure your attic space is adequately sealed and insulated.
Solar air heating systems, which are mounted on an exterior, southern-facing wall or on the roof, can reduce your annual heating costs by as much as 30%. Working in conjunction with your existing heating system, the solar air heating system simply reduces your heating demand whenever you have even partial sunlight. Solar air heating systems are much less expensive than conventional heating systems, and they typically pay for themselves in 6 years or less. They require very little maintenance and have a life expectancy of 20 to 30 years.
High Efficiency Furnaces, Air Conditioners and Heat Pumps
A more significant investment, but still well worth consideration, is replacing your existing heating and/or cooling system with higher efficiency equipment. In addition to standard furnaces and air conditioners with high Energy Star ratings, you may want to look into a traditional or geothermal heat pump. Even though the cost for this type of change is more than many other measures you can take, the payback period is often relatively short.
Hot Water Heating
Traditional hot water heating tanks are usually quite inefficient. Not only are the heating elements power greedy, they also may lose a lot of the heat they produce because they are poorly insulated. If you have an older tank, simply adding an insulating "blanket" may save you energy. But to realize a significant savings, you will want to consider upgrading to a newer, more efficient Energy Star model.
On Demand Hot Water Heaters
On demand hot water heaters are another great way to save money on water heating. Rather than maintaining a large tank of water for use a few times a day, on demand (also knows as instantaneous water heaters) only heat water as it is being used. This can save you 30 to 50% of the cost of heating your water. You can find instantaneous water heaters that use natural gas, propane and electricity from a variety of manufacturers.
Solar Hot Water
Great improvements have been made in solar water heating technology in recent years. Solar hot water is now efficient and effective even in northern climates, where historically it was rarely worth the investment. The right solar hot