5 Things to do Today to Save Energy

Eliminating commercial building energy waste can enhance comfort levels, reduce equipment wear and tear, and lower monthly energy costs. However, not all energy conservation measures (ECM) are obvious or created equal. Ryan Lewton, Director of Energy Consulting & Certified Energy Manager at Key2Act, encourages facility managers to identify the underlying causes contributing to energy waste and incorporate lesser-known ECMs to prevent reoccurrence.

Energy Saver #1: Economizer Control

Economizers are crucial pieces of building HVAC equipment that, when properly installed and maintained, reduce the total amount of energy consumed by evaluating and using outdoor air to cool a commercial building. But these pieces of equipment routinely miss several opportunities to perform their role, especially during the Winter to Spring and Summer to Fall shoulder seasons. The result is lost dollars from unnecessary mechanical cooling costs.

There are many reasons why economizers can be inefficient but there are additional pieces of equipment within the system that should also be investigated along with the economizer to ensure proper overall function. Additional equipment to look at include:

·       Temperature and humidity sensors

·       Barometric relief dampers

·       Building static pressure transducer

·       Correctly sized building humidifiers

Energy Saver #2: Duct Pressure Optimization

Since 1999, ASHRAE has specified duct pressure static optimization (DPSO) as a key energy conservation measure. However, many facility programs do not reset the duct pressure setpoint. This failure leads to wasted fan energy. Common problems your building may incur include poor space temperature setpoint control, undersized variable air volume (VAV), and malfunctioning or uncalibrated VAV boxes.

To improve the duct pressure in your building, review and correct some of the main underlying causes including:

·       Clogged or incorrect duct sample points

·       Removing non-critical areas in the DPSO calculation

·       Using DPSO default or older code requirements

Energy Saver #3: Pump Pressure Optimization

Like Energy Saver #2, few facilities implement pump pressure optimizations, even though all facilities and equipment can support this ECM. Unfortunately, this oversight leads to energy waste as pump energy can, in some cases, equal the chillers’ energy consumption. Common problems include over-pressurizing the piping system, short-cycling equipment, and pump cavitation or damaged pump seals.

Typical root cause analysis reveals the opportunity for:

·       Developing a program to track pump pressure

·       Unclogging differential pressure transducers

·       Resetting routines to run at factory defaults

·       Hunting chilled water valves

·       Properly sampling points in the piping

Energy Saver #4: Occupied Standby

Many facilities fail to use the occupied standby mode on their building automation system (BAS). This function lets the system reset ventilation requirements and space temperatures in partially occupied buildings saving energy and increasing comfort for the remaining occupants. Since unoccupied spaces don’t need to meet minimum ventilation rates, there isn’t a need to keep the same requirements for all areas, like unused administrative offices, within a building that operates 24-hours a day. Common problems linked to a failure to use occupied standby can include occupant comfort issues, elongated recovery time or short-cycling equipment.

To find the causes and prevent future problems in identified spaces, facility managers can:

·       Add motion detectors to ensure equipment only runs when spaces are occupied.

·       Check the BAS settings and reset the settings to factory defaults.

·       Adjust for seasonal temperature and humidity variations to ensure occupants remain comfortable.

Energy Saver #5: Discharge Air Temperature Reset

Simultaneous heating and cooling, arid conditions during winter months, and unnecessary reheat operation are common issues resulting in wasted energy. In many cases, buildings do not use the discharge air temperature resets on their air-handling units.

While a root cause analysis often reveals a failure with the outdoor air temperature sensor, the facility manager should also institute a reset programming schedule or implement an incremental reset for space temperature fluctuations.

Use BOB to Identify Wasted Energy

Facility managers can leverage tools, like the BOB energy utility dashboards, to pinpoint savings opportunities and assess buildings for energy-hungry systems and equipment. Contact us to learn how you can monitor building health and energy use with BOB.

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