Creating an Energy-Efficient Home

Article highlights:

• Fluorescent and LED lighting options
  
• Cost-effective ways to cool and heat your home
  

• Lower energy bills by plugging air leaks
  

Whether you're building a new eco-friendly home or retrofitting your existing home to become more energy-efficient, going green shouldn't have to put you in the poor house. In fact, if done right, it should cost you less. According to research conducted by the Rocky Mountain Institute (RMI), the key component of keeping the costs of green home building and remodeling projects down is through integrated design.

Integrated design actively considers the interconnections between systems, occupants and the environment. It uses these connections to develop single solutions to multiple problems such as energy savings, indoor environmental quality and aesthetics. It also integrates green features from the beginning instead of adding these energy-efficient elements after the home has already been constructed.

'A high water-heating bill might not be solely due to the price of gas or electricity, or even how much energy you use,' says R.J. Crotser, an energy consultant with The Azlan Group. 'The problem might be traced back to leaky water pipes or poor insulation. Your home is impacted by the environment around it and all the factors inside it.'

By viewing your home as a series of interconnected systems, from heating and cooling to lighting, you'll learn to better pinpoint problem areas and find more efficient solutions for your energy woes.

Lighting

In the United States, lighting accounts for 5 to 10 percent of the total energy use in an average home and costs $50 to $150 a year in energy bills, according to the RMI. Advancements in technology have created more energy-efficient lighting options and play a major role in lowering overall electrical consumption in households across the country.

Compact fluorescent lamps and light bulbs (CFLs) are a type of fluorescent lighting, designed to replace an incandescent lamp and can fit in the existing light fixtures formerly used for incandescent bulbs. Compared to general service incandescent lamps that emit the same amount of visible light, CFLs use less power and have a longer rated life but generally have a higher purchase price. In the U.S., a CFL can save more than $30 in electricity costs over the lamp's lifetime compared to an incandescent lamp and save 2,000 times its own weight in greenhouse gases. Like all fluorescent lamps, CFLs contain mercury, which complicates the disposal of fluorescent lamps. Be weary of cheaper CFLs, because the quality of lighting may lack the same kind of illumination as an incandescent.

Light-emitting diode (LED) lighting is often considered the crème de la crème of fixtures, but expect to pay the price with the average cost at $135 per bulb. The upside is you may not have to change a light bulb for the next 20 years in your home. A LED is a semiconductor device that converts electricity into light. LED lighting has been around since the 1960s, but is just now beginning to appear in the residential market for space lighting. LEDs are better at placing light in a single direction than incandescent or fluorescent bulbs. Because of their directional output, they have unique design features that can be exploited by clever designs.

LED strip lights can be installed under counters, in hallways and in staircases, while concentrated arrays can be used for room lighting. Waterproof, outdoor fixtures are also available. Some manufacturers consider applications such as gardens, walkways and decorative fixtures outside garage doors to be the most cost-efficient.

LED lights are more rugged and damage-resistant than compact fluorescent and incandescent bulbs. While LEDs don't flicker, they are very heat sensitive. Excessive heat or inappropriate applications dramatically reduce both light output and lifetime.

Lighting controls

To help you control your light usage, dimmers, timers and sensors can help ensure that lights are turned on and off when needed and adjust to desired luminosity.

• Sensors turn lights on only when they are needed and are more precise than timers, as they respond to actual conditions within the home.
  

• Ultrasonic motion sensors turn lights on and off in response to movement.
  

• Infrared sensors turn lights on and off in response to body heat.
  

• Photo sensors turn lights on and off when ambient light falls below or rises above certain levels.
  

Space cooling

In a typical home, 56 percent of the total energy bill goes to heating and cooling indoor spaces, according to the U.S. Department of Energy. The average air conditioned home uses over 2,200 kilowatt-hours of energy and costs the average homeowner around $200 a year.

Room air conditioners are rated by their energy efficiency ratio (EER) and central air conditioners are rated by their seasonal energy efficiency ratio (SEER). When choosing a central AC unit, Michale Holcomb, President of Alliance for Environmental Sustainability, suggests that using a unit with a higher number EER or SEER will be more energy-efficient and cheaper to operate.

The federal minimum SEER rating for central air conditioning systems is 13. Holcomb says the added cost to purchase a higher-efficiency unit should be weighed against the number of cooling degree days in your location and the difference in cost.

'In our climate zone [in Grand Rapids, MI] the decision to purchase a higher SEER is less important than purchasing a unit that has been properly sized by the HVAC contractor. The smaller the unit the more efficiently it will run, even though it may run longer during the dog days of summer,' said Holcomb.

The average useful service life of a central air conditioning system is 14-years. There is no need to toss out an appliance if it hasn't used up its recommended lifespan and still operates just fine. Creating extra waste would defeat the purpose of going green.

Suggestions on how to maximize AC efficiency:

• Use mastics (sealants), sheet metal screws or metal and plastic bands to seal ducts. You can expect to save up to $300 on annual cooling.
  

• Turn your AC unit off or turn thermostat up when you are not home. Adjusting the thermostat by 10 to 15 degrees during the day when you are not home can save 5 to 15 percent on your energy bills.
  

• Set your thermostat at 78 degrees or higher when the AC is in use. According to research from the U.S. Department of Energy, each degree below 78 increases your energy consumption by 8 percent.
  

• Install room AC units on the north-facing side of your home, away from direct sunlight and near-shaded areas.
  

• Clean filters or change disposable filters monthly.
  

• Hire a licensed heating and cooling professional to conduct yearly inspection and cleaning of your central AC units.
  

Fans

In moderate climate regions, the most cost-effective way to keep a home cool and create ventilation during warmer months is with portable fans, ceiling fans or whole-house fans. Energy Star fans typically use 20 to 50 percent less energy and save homeowners about $25 per year in energy costs, according to the RMI.

Many home builders say whole-house fans work best by providing the strongest air circulation and aid in cooling by pulling cool, fresh air in from lower-floor windows. This air is then typically vented through the roof. The average cost to install a whole-house fan is $500, and operating costs are low, from $0.01 to $0.05 per hour. But one of the drawbacks with these fans are they can be a source of heat loss in the colder months, causing back-drafting from combustion appliances in the home. To prevent heat loss, seal the fan and place an insulated cover over it during the winter.

Heating

There are a variety of technologies available today for heating your house:

• Furnaces and boilers: By far the most common way to heat a home.
  

• Wood and pellet-fuel heating: Provides a way to heat your home using biomass or waste sources.
  

• Electric-resistance heating: Among the most expensive ways to heat a home.
  

• Active solar heating: Uses the sun to heat either air or liquid and can serve as a supplemental heat source.
  

• Radiant heating: Can draw on a number of energy sources, including electricity, boilers, solar energy, and wood and pellet-fuel heating.
  

• Small space heaters: Less efficient than central heating systems, but can save energy when used appropriately.
  

Photovoltaic roof panels that harness solar energy create electricity for the home, heat water, and improve indoor lighting.

Active solar heating

Active solar heating systems are most cost-effective when they are used for most of the year, that is, in cold climates with good solar resources. They are most economical if they are displacing more expensive heating fuels, such as electricity, propane and oil heat. Some states offer sales tax exemptions, income tax credits or deductions, and property tax exemptions or deductions for solar energy systems.

The cost of an active solar heating system will vary. Commercial systems range from $30 to $80 per square foot of collector area, installed. Usually, the larger the system, the less it costs per unit of collector area. Commercially available collectors come with warranties of 10 years or more and should easily last decades longer. The economics of an active space heating system improve if it also heats domestic water, because an otherwise idle collector can heat water in the summer.

Heating your home with an active solar energy system can significantly reduce your fuel bills in the winter. A solar heating system will also reduce the amount of air pollution and greenhouse gases that result from burning fossil fuels such as oil, propane and natural gas for heating or generating electricity.

Plugging leaks

Sealing against air leaks is one of the most important things your builder can do to ensure overall comfort and lower energy bills in your new home. The exterior of your home is called the 'envelope' or 'shell.' It is common to find both older and newer homes with poorly performing 'envelopes' and poor insulation.

Most air-leakage problems are found in the areas listed below. Make sure your builder has identified these potential trouble spots in your home building plan and that steps will be taken to properly seal before adding insulation:

• Floors
  
• Utility and other vented areas
  
• Staircases on outside or garage walls
  
• Holes for wiring and plumbing
  
• Where walls meet floors and rooflines
  

• Chimneys and fireplaces
  
• Windows
  
• Attics and attic access
  
• Knee-walls and dormers
  
• Duct systems
  
• Bathtubs or showers on outside walls
  

Leaks in the duct system, even tiny ones, waste energy much like a leaky faucet wastes water. The more air lost through duct leakage, the more you're paying to heat and cool your home. Duct-system leakage can account for up to 30 percent or more of wasted energy, according to Energy Star officials. Furthermore, because air quality is another important consideration, proper duct sealing also keeps dust, mold and mildew in crawlspaces and attics from passing into your home and into your lungs. Your contractor should permanently seal your entire duct system with mastic or UL 181-rated tape.

Ducts are commonly concealed in walls, ceilings, attics, basements or crawl spaces, making it difficult to access and repair. The Environmental Protection Agency recommends using a professional contractor for duct improvements and sealing. It is also important to have your local heating and cooling contractor perform a combustion safety test after sealing air leaks to be sure all your gas or oil-burning appliances are working properly. Energy Star officials recommend that you do the test during your annual heating system check-up.

Buying a green home or retrofitting your exiting property to be more energy-efficient ought to be more than just a passing trend. In a world were energy is not infinite, finding ways to converse and reduce our carbon footprint will improve the quality of our lives today and the lives of a future generation.

Next article: Green Qualities to Look for in a Home >>

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