HVAC systems account for approximately one-third to one-half of the total energy consumption in residential buildings. For homeowners, air conditioning is a huge portion of this energy use. In fact, more than 80 percent of homes in the United States have air conditioning, and some 16 percent of residential electricity use is from air conditioning for both room and central units.
With people spending an average of 50 percent of their time in their homes, energy consumption in residential buildings is greater than in commercial buildings. This means the use of high-performing and energy efficient HVAC systems can result in significant energy and cost savings, as well as shield people against rising energy prices.
In the past, ventilation in residential buildings was not a major concern because of the belief that enough outdoor air could be obtained by air leaking through the walls of the home and simply opening windows.
As homes and duct systems were built tighter as an energy saving measure, homeowners became less likely to open windows because of energy costs, security issues, noise and outdoor pollutants. Additionally, a rise in trapped contaminants inside homes and overall indoor air quality issues accompanied these concerns.
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has provided a few helpful tips to help you better conserve energy and make the most of your air conditioning systems.
Set thermostats to 76 degrees Fahrenheit or above when the house is occupied during the day and a few degrees higher at night. In hot and humid climates, the nighttime setting should be adjusted to keep humidity at a comfortable level. Programmable thermostats can do this automatically and easily. Many are inexpensive, reliable and easy to install with minimal tools needed.
Optimize air circulation
Installing ceiling fans, especially in hot and humid climates, allows occupants to set the thermostat higher by taking advantage of air circulation, thus reducing the time the air conditioner is on.
Opt for energy-efficent equipment
Whenever possible, always select energy-efficient equipment when buying heating and cooling equipment. Your HVAC professional should be able to give you energy fact sheets for different types, models and designs to help compare energy usage.
Regularly schedule maintainance
Finally, regular maintenance, twice a year, from an HVAC professional can keep your air conditioner running efficiently.
Building a new home
While the above tips will help existing residential spaces, the real key to minimizing indoor air pollutants and maximizing energy efficiency is through the design of HVAC and other systems that work together to effectively ventilate the home. Guidance from ASHRAE for home ventilation will generally result in improved indoor air quality and decreased health problems compared to those that do not get ASHRAE guidance. ASHRAE Standard 62.2, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings is the only nationally recognized indoor air quality standard developed solely for residences and is intended for use in building codes.
ASHRAE is focused now more than ever on better serving the residential marketplace through research to improve indoor air quality. With more than 56,000 members worldwide, ASHRAE is working to continuously create and advance toward a future where the built environment is healthier, more comfortable and more energy efficient, which will, in turn, produce a more sustainable world for future generations.
Bjarne W. Olesen Ph.D., President, ASHRAE, [email protected]