An energy auditor, much like a CxA, reviews the building operation with the goal of improving it. However, he or she focuses primarily on the building’s energy use. The energy auditor compares utility data to a database of similar buildings and climates to determine the potential savings. He or she reviews system operation to restore equipment to its original design conditions and make improvements to the sequence of operations. The energy auditor also will make recommendations for energy-conservation capital improvements and provide economic feasibility analysis to determine return on investment for the owner. Unlike commissioning agents, many energy auditors do not carry any specific accreditations. However, many energy auditors are also Certified Energy Managers, which is a designation administered by the Association of Energy Engineers, or AEE. AEE has also recently developed the Certified Energy Auditor designation. To find an energy auditor, check with your local utility company or www.energystar.gov.
Some may argue hiring an energy auditor is better than hiring a commissioning agent because they seem to do what a CxA does, as well as provide a detailed analysis of your energy use and solutions to reduce it. However, a CxA will ensure your building’s systems are operating correctly whether related to energy, comfort, IEQ or safety. If your primary goal is to ensure the building is operating properly and make some energy improvements along the way, hire a CxA. If your goal is to simply save energy but not directly focus on other aspects of your building’s operation, hire an energy auditor.
Don’t forget your favorite HVAC service contractor. Although he or she may not perform full commissioning or auditing services, your service contractor already knows your HVAC systems and can find ways to make operational and controls improvements.
Replace Your Thermostat
The most common HVAC recommendation a CxA or energy auditor will make is to replace your thermostat. Nearly every house and building should have a programmable thermostat. If you already have one, is it actually programmed? Many existing buildings run heating and cooling 24/7 despite only being occupied 12 hours per day, five days per week. Using a pre-programmed schedule to turn systems off or set them back when a facility is unoccupied can save approximately 25 percent of energy costs for a very low investment.
The most common HVAC recommendation a CxA or energy auditor will make is to replace your thermostat. Nearly every house and building should have a programmable thermostat. If you already have one, is it actually programmed?
Some tweaking will be necessary on each installation to find the ideal number of degrees to set the system back and the optimal time to start the system the next day. However, because of the low installed cost, an energy savings payback period of less than six months is common.
Adaptive Intelligent Recovery
You should also consider using a thermostat that has Adaptive Intelligent Recovery, also known as Smart Recovery or Adaptive Optimal Start. This concept takes the programmable thermostat one step further by using recent history to determine the best time to start a system each morning to achieve the desired setpoint at the desired time. The most common HVAC recommendation a CxA or energy auditor will make is to replace your thermostat. Nearly every house and building should have a programmable thermostat. If you already have one, is it actually programmed?
Instead of programming a system to enable at 6 a.m. to have the space comfortable by 8 a.m., you can program the thermostat for 8 a.m. and it will know what it needs to do to ensure the space is optimally heated or cooled by 8 a.m. Each minute the thermostat is able to delay startup will save energy beyond what a standard programmable thermostat could save. The incremental cost for an Adaptive Intelligent Recovery thermostat versus a standard programmable thermostat is very low; an energy savings payback period of less than one month is common.
Be careful not to implement too large of a temperature setback. In some cases, allowing the thermostat to be set back too far may use more energy to recover from setback than if you didn’t do anything at all. Make sure you have at least six hours of unoccupied time and try to set back about 5 degrees. I like to use 65 F for heating and 80 F for cooling.
If you are using the thermostat with intelligent recovery, do not schedule the start time too early. Set it for the actual time people will start arriving at the building and be patient; it can take seven days or more for the thermostat to start building a history to make accurate predictions about the required start time each day.