Energy Saving Tips

  • What Size Heat Pump Do I Need?

    There are many different types of heat pumps and efficiencies, but there is another important factor if you’re considering a new unit—purchasing a properly-sized unit. Because your heating and cooling system is one of the more costly purchases for your home, it is important to understand how to know your unit is the correct one.

    When dealers talk about the size of a heating and cooling unit, the measurement is in tons, where 12,000 BTU/h equals one ton of heating and cooling. There are a few ways a dealer can determine the size unit needed for your home: replacing the old unit with the same size, using a “rule of thumb” or perform­ing a load calculation, which is the best method.

    In many cases, when it’s time to replace a unit, dealers will typically put in a system that is the same size as the previous system. But if you have made any kind of energy effi­ciency improvements to your home, the unit may not be the right size for the current household and could be oversized. When it comes to your home’s heating and cooling system, bigger isn’t always better. Not only would you pay more at the point of sale for the unit, but down the road, you may be paying higher power bills since your system will not be as efficient as it should be. Another method to sizing a unit is to use a “rule of thumb” where the unit is determined mostly by the square footage of a home. This is something that has been done for many years and often leads to the installation of an oversized unit, since using this option does not take into account any aspects of the home, such as insulation levels or types of windows and doors, which should also be considered when determining the size of the unit needed.

    The most accurate way to deter­mine the size needed for a home is to do a load calculation. Air Conditioning Contractors of America (ACCA), the governing body for air conditioning contractors, devel­oped a manual for contractors to fol­low in order to determine the size of a unit— the Manual J. The Manual J load calculation takes several items into ac­count to determine the size of the unit, including the dwelling’s square footage, volume of the home, size and type of windows, doors, walls and floor, the direction the house faces, type and amount of insulation, number of people living within the home, air infiltration, appliances and more to accurately determine the amount of BTU/h needed to properly and efficiently heat and cool the home. Once the BTU/h is determined, ACCA developed additional guidelines for selecting equipment and designing the duct work. There are several programs contractors can use that follow these ACCA-approved principles.

    When you receive quotes from contractors, remember to ask how they determine the proper size of the unit. They should do a load calculation, verify the duct is designed correctly and pick the appropriate equipment.

    Remember, a properly-sized unit will mean that you are getting the most value from the power you and your family consume.

  • Taking the Window Pain out of Energy Bills

    Windows can add a pleasing appeal to a home—they let in natural light, offer a view to the outdoors and add to a home’s overall appearance, but they can also be the culprits of costly air leaks. During the winter, many homeowners explain how they feel noticeably cold air near their windows. There can be several reasons for this. First, windows offer the smallest amount of protection from the weather conditions outside. If you think about it, your home’s walls are, on average, eight inches to one foot thick, and consist of wood, insulation and sheetrock, offering you several layers of protection from the elements. A window, on the other hand, does not offer much depth, or significant temperature resistant surface between you and Mother Nature.

    Additionally, many people may feel cool air concentrated around windows due to drafts caused by gaps. These gaps can be large enough for you to see or so small, you don’t realize they exist. So what can you do to take the “pain” out of windows that allow outside air infiltration? One option is simply caulking around the window frame. Caulking windowsill gaps is a fast and inexpensive way to keep cold air out during the winter.

    Another option to block the cold is to install insulated, or black out, curtains. These curtains aid by adding an extra layer of material against cold air, which can reduce heat loss through the window by as much as 25 percent. Throughout the winter, insulated curtains should be open during sunny days to allow the sun’s radiant heat to help warm the house and closed on cloudy days and at night to help keep the heat inside.

    Many people often ask if replacing their windows is a good investment since they can be costly to upgrade. On average, it can take three to seven years or longer to receive a payback.

    But if you do decide to replace your home’s windows, there are some features you should look for. Double panes (or two sheets of glass) offer a thicker barrier for your home from the outside temperatures than do single panes. Double-paned windows contain a type of gas in between the panes as well as a coating on the glass. The gas between the panes is heavier than air and reduces the movement of air. Low emissive coatings on the glass (Low-e) are used to block the heat from the sun and are another beneficial feature to request. The frame of the window also plays a role and should be constructed of either vinyl or fiberglass, both of which offer a higher value of energy efficiency than wood-framed windows, which can decay over time, allowing air leaks.

    Also, look for Energy Star-rated energy efficient windows. These windows are double-paned and include two numbers showing the efficiency of that particular window: the U-factor and the Solar Heat Gain coefficient. The U-factor measures how easily heat can flow through the window and should be .35 or less, the lower the number, the more energy efficient is the window. The Solar Heat Gain Coefficient, which should be .30 or below, depicts the window’s ability to absorb heat from the sun, and is more important during Alabama’s long summer months.

  • Choosing a Heat Pump System

    When choosing a heat pump system, there are two considerations you should keep in mind– the efficiency of the unit and type of unit. The efficiency of the unit is stated with the Seasonal Energy Efficiency Ratio (SEER) – the higher the SEER number, the greater the efficiency and therefore greater energy savings. Ac­cording to the Department of Energy, a 14 SEER heat pump is the standard and it is also the most commonly used because it is the least expensive.

    To help you reach an optimal level of efficiency as well as comfort, let’s talk about the heat pump and the options you have in choosing one to serve your cooling and heating needs. The most common unit is the air-source heat pump, which pulls the heat out of indoor air and releases it outside to keep your home cool and dry and does the reverse in winter. A heat pump acts as a dehumidifier and can trim the amount of electricity you use for heating by 30-40 percent when switching from an electric furnace.

    Another type of unit that can heat and cool your home is the dual fuel heat pump, similar to air source heat pumps, but this one uses a gas furnace as backup heat rather than electric strips. These units switch from the heat pump to the gas furnace only when the temperatures dip below freezing when the heat pump would be less efficient. A dual fuel heat pump is typically more expensive than regular heat pumps but is worth the cost due to reduced energy use in the winter months.

    The mini-split, a compact and efficient way to control the temperature of your home, is a system that consists of an outdoor unit connected to one or more indoor units. This system gives you the ability to zone and control the temperature of each individual indoor unit allowing the members of your home to have control of their space and level of comfort. Some other unique benefits of this system include reaching high levels of efficiency, a possible SEER as high as 18–19. SEER shows the efficiency of a unit during a particular season (cooling), so the higher the rating, the more efficient the unit will work (the standard rating for a heat pump is 14). It can also operate effectively during low temperatures; therefore, it can be used year-round efficiently in varying climates where other systems might not function as effectively. Having a mini-split system allows the option of having no ductwork, thereby reducing the inefficiencies common with ductwork.

    The geothermal heat pump uses heat from the ground or a water source rather than outside air to move heat in and out of the house and can achieve a higher efficiency than air source heat pumps. It is considered to be the most efficient type of heat pump available, and also the most expensive. These units use the constant temperature of the earth as its exchange medium instead of the outside air, and they have a life span of more than 20 years if properly maintained. Although the installation cost may be higher compared to other systems, it will produce lower utility bills and annual maintenance costs. The installation of one of these systems can also provide the homeowner with a 30 percent tax credit. And you will experience a savings of 30–70 percent compared to other systems.

    Learn more about our heat pump rebate program, or call (800) 545-5735, ext. 2118.

  • Air Sealing Your Home

    When you turn on your air conditioner or heat unit, you often make sure all windows or doors are also closed so your en­ergy dollars don’t go flying out the door. This same principle is also true when it comes to cracks and holes throughout the house. These air leaks cause your cooling/heating unit to run longer and harder and in some cases, there may be enough cracks around the house that if you added them all together, it would be about the size of an open window.

    Air sealing your home, both inside and out, is one of the most cost-effective ways to improve energy ef­ficiency and comfort. Ac­cording to a report by the Oak Ridge National Labo­ratory and Pacific North­west National Laboratory, homeowners can save 10-20 percent on their heating and cooling costs just by closing up those air leaks. Buy a tube of caulk and a can of sprayfoam and seal anywhere you see a crack or hole. When you seal your home, it stops air from moving freely between the out­side and inside of your house. So how do you determine where to seal around your home?

    A good strategy is to simply walk around the outside of your home and caulk or foam any openings you see, especially around pipes or wire penetrations. Additional air leaks and drafts are easier to find because you can feel for them – such as those around windows and doors.

    Inside your home, the main area for air leaks is where your wall meets the floor or ceiling. Typically there is molding in place and you can caulk around the molding. Other com­mon places include air penetration points in the ceiling, such as near ceiling fans and lights and the attic access. Sealing these leaks with caulk, spray foam or weather stripping can have an impact on improving your comfort and aide in reducing your utility bills.

    Leaks also allow moisture to come into your home. Your cooling unit regulates both tem­perature and humidity, but when moisture is added to your home, it can become very humid and uncomfortable, especially during the hot Alabama summers, causing your unit to run even more.

    A tube of caulk and a can of spray foam are fairly inexpensive, and sealing your house is an easy way to lower your energy bills while gaining comfort.

  • Do It Yourself Attic Insulation

    Have you looked in your attic lately? Insulation in your attic is an essential component to help keep your home warm in the winter and cool in the summer. While the cooler temperatures are making your attic more comfortable, it’s the perfect time of year to re-apply attic insulation before the hot summer heat arrives.

    There are numerous types of insulation to choose from, and each has a different method of installation. The example below uses cellulose–an easy “do it yourself” process.

    Supplies:
    Cellulose Insulation

    Tools:
    Insulation Blower
    Machine
    Gloves
    Goggles
    Breathing Masks

    Directions: Purchase the cellulose insulation at your local hardware store where you should also be able to rent an insulation blower. The amount you need will depend on the square footage of your home and the thickness of the existing insulation. Make sure the thickness of your insulation (including any existing insulation) is between 12 and 15 inches, which should give you an R-value of 38. You will need at least one person to assist you in applying the insulation.

    Installing Cellulose Attic Insulation:

    1. Place the insulation and the blower machine outdoors. DO NOT operate the machine indoors.

    2. Take the blower’s tube up into the attic with you (through a window or door in the house). Make sure you are outfitted with gloves, goggles and a breathing mask.

    3. Have the person (also outfitted with gloves, goggles and a breathing mask) stationed near the blower machine begin to feed it with the loose, cellulose insulation, one bale at a time. When ready, this person will also control the flow of the insulation by using an on/off switch or a lever that allows insulation to pass through.

    4. In the attic, sweep the blower’s tube in the locations where you desire the insulation. When finished, have the person stationed with the blower turn off the machine.

    On average, an 1,800 square foot house will take approximately four hours to complete at a cost of $500. Prices and times may vary due to retailers, square footage and depth of existing insulation. On a house with little or no pre-existing insulation, adding more—and doing it yourself—can help make your home more comfortable and provide some cost savings to your power bill.