Places to Look for Energy Losses in Commercial Buildings

Data from millions of businesses, institutions and manufacturers show that sustainability issues fall into four main categories: rising energy costs, growing disposal costs, limited water supply and health concerns over the quality of indoor air.

Energy is often the largest line item in an operations facility management bill. So, monitoring and reducing excess energy use throughout your facility can lead to savings. My company worked with one of our 3,000 supplier partners, Fluke Corporation, to identify these top places to look for energy losses in commercial buildings.

According to Fluke Corporation, a significant amount of energy loss is actually temperature-related. Hot or cold air leaks from a building are obvious examples. It took energy to condition that air, and when it dissipates due to a leak, you’ve wasted that energy. Many other systems and pieces of equipment also manifest their energy in terms of heat. Motors, pumps and electrical boxes will generate heat and lose energy efficiency as they begin to fail.

Thermal imagers create pictures by measuring infrared energy or heat and then assigns colors based on the temperature differences it measures. Thermal imaging experts suggest that maintenance teams inspect the following systems to identify energy losses:

–HVAC System: The heating, ventilation and air conditioning (HVAC) system is usually one of the biggest areas of energy consumption within a facility.

What to Scan

• Ductwork and Registers. Even the highest-rated HVAC system wastes energy without a well-sealed duct system. With infrared technology, one can see the thermal pattern of air in ducting and monitor registers to determine whether heating or cooling output is optimal.
• Fans and Blowers. In fans and blowers, mechanical imbalance will manifest itself in overheated bearings and other components. Thermal images of these systems can also identify shaft misalignment in couplings between the motor and fan.
• Electrical Connections. A loose or corroded connection increases resistance at the connection, resulting in overheating.

–Motors and Generators: Electrical motors also use a significant amount of energy in a facility. Overheating and malfunctioning motors and generators tend to indicate mechanical or electrical inefficiencies that can lead to more energy use and ultimate failure.

What to Scan

• Airflow. In fan-cooled motors, a restricted airflow will cause general overheating manifesting itself on the entire housing.
• Insulation Look for higher than normal housing temperatures in areas associated with windings.
• Electrical Connections.  As with electrical connections in HVAC systems, look for loose or corroded connections that increase resistance.

–Steam Heating Systems: Today, steam systems are more common in industrial settings than commercial settings, but some commercial buildings still use them for central heating.

Where to Look and What to Look For

• Radiator Coils. Check for leaks by conducting inspections similar to those of HVAC ducts.
• Steam Lines and Valves.  Look for telltale signs of leaks and blockages and for blow-by at valves that are supposed to be “closed.”
• Condensers. Look for leakage of outside air, which reduces the condenser’s vacuum, thereby decreasing its efficiency.

–Boilers: Boilers, of course, are the heart of steam and hot water heating systems.

What to Scan

• Boiler Casing Insulation.  Look for heat loss from damaged insulation.
• Fan Motors.  As with motors in other applications, check for impeded airflow, electrical unbalance, overheated bearings and failing insulation.
• Pumps.  Look for hot bearings, leaking seals and, as with fans, motor faults.
• Valves.  Thermography can identify blocked valves that are nominally open and leaking valves that are nominally closed.

–Electrical System: Many people don’t realize that electrical systems can actually waste money. As components degrade and resistance increases, incremental waste can occur.

What to Scan

• Distribution Panels. Check for unbalance in circuits and loose and corroded connections at breakers, contacts, fuse clips, busses, etc.
• Transformers. Monitor high- and low-voltage bushing connections, cooling tubes and cooling fans and pumps. Look for overheated connections, comparatively cool cooling tubes and hot or cool pumps. Be aware that if the temperature of one electrical leg on a transformer is significantly hotter than the others, that leg may be failing.
• Lighting Control Circuits. Check all wiring splices and connections at fuses, switches, and fixtures. Be aware also that thermography can also be used to monitor low-voltage control circuits.

With a small amount of training, most people can use thermal imagers to readily spot abnormal temperatures and follow the heat trail to energy waste. The technique works best when used by people who already possess a good working knowledge of the structures and systems being scanned and can better interpret the temperature variances they see on camera. Thermal imagers have come down so far in price that most facilities can recoup the cost of purchase in terms of energy savings within a relatively short period of time.