Energy Star Heating and Cooling

Heating and cooling accounts for almost half of the total energy used by a typical residential customer. Independent of specific purchasing decisions and the choices regarding the selection of heating and cooling equipment, there are a number of operating and maintenance activities consumers should do to maximize the efficiency of these devices These activities include:

• Changing Air Filters: Residential customers should check their filters every month (particularly in the winter and summer) and change it if it looks dirty (or at a minimum frequency of every 3 months). Failure to do so will likely result in the slowing down of air flow  which leads to wasted energy as the system will have to work harder to keep the home warm or cool and expensive corrective maintenance due to premature system failure.
• Annual Tune Ups: It is important to annually check thermostat settings, tighten electrical connections, lubricate of all moving parts, inspect the condensate drains, and check system controls. For cooling systems, tune-ups should include cleaning the evaporator and condenser air conditioning coils, checking the refrigerant level and cleaning and adjusting the blower components. For heating systems, the tune-ups should include checking all gas (or oil) connections, gas pressure, burner combustion, and heat exchanger.
• Installing a Programmable Thermostat: Presented below, a programmable thermostat captures the energy savings opportunities related to people being away from home for set durations of time throughout a typical week.
• Sealing Heating and Cooling Ducts: Recognizing that insufficiently sealed ducts that move air to-and-from a force air furnace, central air conditioner, or heat pump can significantly impact energy efficiency (by as much as 20 percent), the use of duct sealant (mastic) or metal-backed (foil) tape on seams and connections of ducts (followed by the wrapping of the ducts in insulation (particularly in the attic, crawlspace, and unheated basement or garage) can have a dramatic impact on the efficient operation of the overall heating and cooling system.

Energy Star Qualified Equipment

ENERGY STAR qualified heating and cooling systems, particularly if a consumer’s current systems are more than 10 years old and/or is not performing efficiently, may offer an opportunity to reduce one’s current energy bill while simultaneously participating in a variety of initiatives around reducing greenhouse gases. Though the ENERGY STAR qualified equipment is generally more costly up front (i.e. higher initial purchase price), the potential savings to be realized by the residential customer is significant enough to offset the increase within a reasonable period of time (typically 3 to 5 years). Further, these specific models are found to operate more effectively, increasing the overall comfort of the home (less noise and improved performance).

The following discussion explores the opportunities present among 11 categories of heating and cooling related equipment, and then highlights some key considerations in properly installing the equipment,

Categories of Heating and Cooling Equipment

Central Air Conditioners for Consumers: Recognizing that heating and cooling costs the average residential customer about $1,000 per year (50 percent of the average energy bill), replacing the current air conditioner (particularly if it is more than 12 years old) by an Energy Star qualified central air conditioner could:

• Reduce cooling costs by as much as 30 percent
• Promote cleaner air (reduce pollution)
• Enhance comfort

Though more expensive to purchase, the cost difference is recoverable over time due to the lower energy bills.

Room Air Conditioners: ENERGY STAR qualified room air conditioners use at least 10 percent less energy than conventional models and offer significant reductions in greenhouse gas emissions. In fact, if every room air conditioner sold in the U.S. was so qualified, over 1.3 billion pounds of GHG emissions would be prevented.

Boilers: ENERGY STAR qualified boilers have an annual fuel utilization efficiency (AFUE) rating of at least 85 percent, and use 6 percent less energy than a “conventional” boiler. Key features driving this increased efficiency include:

• Electric Ignition (i.e. avoids continuous burning of pilot light)
• Improved Combustion Technologies (i.e. more efficient extraction of heat from fuel)
• Sealed Combustion (i.e. uses outside air to fuel boiler)

Dehumidifiers: Potentially saving residential customers $20 per year, ENERGY STAR qualified dehumidifiers use 10 to 20 percent less energy than similarly sized “conventional” models to remove moisture.

Ceiling Fans: In selecting an ENERGY STAR qualified ceiling fan (which is typically 50 percent more energy efficient that a “conventional” unit), consumers should also consider ENERGY STAR qualified lighting (if appropriate). Typically, the average residential customer can anticipate saving $15 per year (per fan/light combination) on utility bills.

Ventilating Fans: Typically used with kitchen range hoods, or as bathroom, utility and inline fans, ENERGY STAR qualified ventilating fans use 70 percent less energy on average than “conventional” models and provide:

• More comfort
• Less noise
• High performance motors and improved blade design that last longer

Furnaces: ENERGY STAR qualified oil and gas furnaces typically have AFUE ratings between 85 and 90 percent, and operate 15 more efficiently that “conventional” models. As with most ENERGY STAR qualified products, though more expensive to purchase, the cost difference is offset in time by the lower energy bills.

Air-Source Heat Pumps: Using the difference between outdoor and indoor air temperatures to cool and heat homes, electric air-source heat pumps have a higher seasonal efficiency rating (SEER) and heating seasonal performance factor (HSPF) than the more “conventional” models, making them 8 to 20 percent more efficient than the more “conventional models on the market or currently installed in homes.

Geothermal Heat Pumps: Though similar to the air-source heat pumps, geothermal heat pumps use the ground instead of outside air to provide heating, air conditioning, and hot water; making them among the most energy efficient and comfortable heating and cooling technologies available on the market. With the recently established ENERGY STAR specification, qualified geothermal heat pumps are expected to achieve a 45 percent improvement in energy efficiency when compared with the “conventional” options.

Light Commercial Heating and Cooling: Space cooling, second to lighting in terms of energy use in commercial building, accounts for approximately 15 percent of energy consumption. In replacing “conventional” heating and cooling equipment with ENERGY STAR qualified light commercial HVAC equipment, users can anticipate a 7 to 10 percent reduction in energy consumptions. This equates to a $3 to $4 per square foot savings over the life of the equipment.

Programmable Thermostats: Residential customers can save $180 per year by properly setting their programmable thermostats and maintaining those settings. In order to optimize the use of these devices and realize these savings, one must establish a program that automatically reduces heating and cooling in one’s residence when appropriate; and the ENERGY STAR Programmable Thermostat Calculator to determine the proper set-back temperatures (within an existing framework) to maximize these savings.

NOTE: Only those products listed by an Energy Star partner are officially recognized as ENERGY STAR qualified.

Installation Tips

Failure to properly install new equipment can reduce the potential system efficiency benefits by as much as 30 percent and thereby significantly impacting the ability to recoup the up-front investment through lower energy bills and even shortening the life of the equipment. As a starting point, an installation contractor should be required to meet the standards specified by Energy Star and the Air Conditioning Contractors of America (ACCA), including:

• Properly Sizing the Equipment: In order to achieve the best performance and comfort of the equipment, it must be sized correctly. Obviously, a system that is too small for the home will be overstressed and inadequate; but a system that is too large will experience frequent “on/off” cycling which will place undo stress on the components and therefore, shorten the equipment’s life.
• Sealing the Ducts: Leaky ducts can be identified through use of a leakage rate test and then, sealed applying the above described process (use of mastic and/or foil along with insulation). Failure to do so can result in air leakage in the range of 20 percent (an obvious waste of heat or cooling).
• Properly Charging the Refrigerant (applies to Central Air Conditioners and Heat Pumps): This requires the test and confirmation that the system is properly charged (i.e. has the correct amount of refrigerant); and then either the addition or removal of refrigerant as necessary.
• Optimizing Air Flow: Higher or lower than normal air flow will result in higher utility bills, but can be easily adjusted by the contractor during installation (and subsequent system tune-ups).