Energy conservation is a priority for everyone, and in today’s economy, it’s more important than ever to manage your energy expenditures.

Below are some operational tips to help you save energy in existing buildings.

GENERAL

• Verify that the design conforms to or surpasses the latest energy standards and codes.
• Keep operation-and-maintenance documentation and practices up-to-date. Ensure that operations and maintenance staff are well-trained and proactive in their duties.
• Establish energy-consumption and demand goals, track and discuss them with operations staff at regular intervals.
• Work as a team to optimize the design, construction, and operations phases of your building.

BUILDING ENVELOPE

• Use vestibules and revolving doors at building entrances. The use of these doors can reduce infiltration by 75 percent compared with standard single and double-leaf doors.
• Specify Low E, double- or triple-pane argon-filled glass with a factory-applied coating (low shading coefficient).
• Use interior blinds and/or shades to reduce cooling loads during peak hours.

BUILDING CONTROLS

• Design controls for straightforward operation and maintenance. Easy to use controls will be used more fully.
• Keep the control system operating as designed by correcting problems that require manual overrides and other performance-limiting fixes.
• Upgrade controls or the control system when feasible. The replacement of pneumatic systems with direct digital control is particularly effective.
• Utilize a maintenance program that includes periodic checks for broken, stuck, or loose dampers, linkages, control valves, and other control devices.

AIR SYSTEMS

• Convert constant-volume fan systems to variable-air-volume (VAV) systems to eliminate excessive air volume and energy use at part-load conditions.
• Replace mechanical air-volume-control VAV systems with variable-frequency-drive (VFD) air-volume controls.
• Avoid the use of preheat and reheat coils, as well as lockout operation of such coils, when possible.
• For VFDs and soft-start fans, use synchronous belt drives for higher efficiencies. Synchronous belts can save as much as 5%.
• Periodically re-evaluate loads to ensure that the HVAC system and components are properly sized and operationally balanced.
• Maintain good control of outside air to eliminate excessive outside-air flow at extreme temperature conditions while maintaining adequate air quality at all times of occupancy. Use enthalpy control for air economizers.

EXHAUST SYSTEMS

• Shut off exhaust fans during all unoccupied cycles except economy purge cycles.
• Check exhaust systems to ensure that they are exhausting only the amount of air required. If possible, reduce exhaust-air quantities from toilet rooms, laboratories, etc. to minimum acceptable levels.
• Control room and process exhaust fans to operate only when a room is occupied or equipment is running.
• Install energy-recovery devices to reclaim energy from building and process exhaust-air systems.
• Maintain operational strategies to keep laboratory fume-hood doors closed and exhaust fans off when they are not in use.

STEAM AND HYDRONIC SYSTEMS

• Reset chilled-water and heating-water temperature in accordance with actual loads.
• Optimize cooling-tower operation and use cooling-tower water for a water-side economizer (free cooling), instead of operating the chiller, when possible.
• Find and stop steam leaks; institute a trap, vent, and strainer-maintenance program; and insulate steam, hot-water, and condensate lines.
• Replace old chillers and boilers with new, energy-efficient equipment.
• Convert from constant-flow to variable-flow hydronic systems with VFDs to reduce hot and chilled-water flows at part-load conditions.
• Whenever possible shut down the boiler plant and/or replace with smaller boilers and water heaters during low load periods such as summer.
• Ensure that all condensate is returned to the boiler plant.
• Consider replacing PRVs with back-pressure steam turbines for pump and fan drives or electric generators. A back-pressure turbine can operate as a PRV valve to meet low-pressure-steam needs.
• Use low-flush (1.6-gpm) toilets, occupancy sensors at flushometers, etc.

MISCELLANEOUS

• Periodically retest, balance, and adjust air and hydronic systems.
• Re-commission building systems after retrofits and renovations.
• Improve access to filters, coils, and other system components to make maintenance easier and more frequent.
• Optimize multiple-chiller operation to stage chillers for maximum efficiency and the lowest electrical demand.
• Reduce heating and raise cooling set-points in unoccupied areas.
• Notice when personal heaters and fans are being used. Find out why and then solve problems with the building HVAC system.

ALTERNATIVE ENERGY

• Consider installing solar collectors to heat domestic and process water.
• Consider installing photovoltaic roof-top panels and curtain wall panels.
• Consider infrared heating in place of forced-air heaters for areas subject to much outside-air infiltration.

COMBUSTION EQUIPMENT

• Periodically check and adjust fuel-air ratios on combustion equipment.
• Consider installing automatic air-gas combustion controls.
• Replace indirect-fired makeup-air units with direct-fired equipment when feasible.
• Preheat combustion air with waste heat.

INDUSTRIAL PLANTS

• Update plant heating and air-conditioning systems as comfort and process requirements change.
• Consider changing process schedules to shift load periods and peak electric-demand.
• Shut off machinery when not in use, such as during lunchtime.
• Keep covers on tanks and vats closed to reduce evaporation losses.
• Use cold-water detergent in washers whenever possible.
• Combine operations when possible to reduce the number of washers.
• Install destratification equipment in high-bay plants to reduce heat loads during the winter by heating at the floor level.
• Use spot heating or cooling for people when they are located far apart.
• Determine whether pressure blowers could replace some compressed-air usage. Do not use compressed air at higher pressures than required.
• Design for reduced exhaust air with the use of local, rather than general, exhaust systems, such as ventilated welding guns, hoods for portable grinding equipment, and local traveling hoods for molten-metal pouring.
• Consider recycling industrial-waste streams.
• Consider heat recovery from industrial exhaust air.
• Determine the feasibility of utilizing waste heat in production operations before exhausting it.
• Use proper-sized high-efficiency motors operated by VFDs when capacity requirements fluctuate.
• Apply power-factor correction when possible.
• Stage the startup of loads to keep demand down, and install demand-limiting equipment.
• Connect lighting with comfort-conditioning systems to the building automation system to minimize energy use in unoccupied areas.

LIGHTING AND POWER

• Design and retrofit high-efficiency lighting systems.
• Reduce excessive illumination.
• Lower hanging height of light fixtures to increase light levels and to allow retrofit to lower lumen/lower wattage light sources.
• Consider utilization of a group relamping program.
• Install daylight harvesting controls and dimming ballasts.
• Utilize multiple switching for selective lighting levels in offices, conference rooms, etc. Utilize dimmers to have the light level match the task.
• Reduce lighting in areas that do not require high levels of it, such as stockrooms and corridors.
• When redecorating, use light colors on ceilings and walls to increase reflectivity and achieve good illumination levels with less lighting.
• Use timers or photocells to control outdoor lighting.
• Install motion sensors to implement bi-level lighting or turn lighting off when specific areas are unused.
• Reduce parking-lot lighting to the minimum levels required for safety.
• Replace low-efficiency fixtures (HID and HPS) with high-efficiency fixtures (T8 and T5 fluorescent).
• Install motion sensors and dimmable fluorescent fixtures in warehouses for maximum energy savings.