RCM Exchange

Control Systems

An energy management control system (EMCS) - a powerful tool to help save energy - will likely be installed in any new facility. An EMCS can be programmed to provide:

  • Historical monitoring functions, useful when diagnosing problems such as a demand spike on an electric bill
  • Trend logs of equipment performance
  • Trend logs of space temperature measurements
You could program the EMCS to give you temperature readings in a particular room every minute, but because an EMCS typically has a maximum number of trend points, it would save only a few days-worth of information. If you reprogrammed it to record the temperature every 10 minutes, you may be able to get a trend log for a whole month. You could also trend the “on” and “off” cycles of equipment.

Many EMCSs also have electric load-shedding capabilities, typically accomplished by:

  • Prioritizing loads. For example, an electric domestic hot water tank could be shed first when the predetermined maximum load is reached.
  • Duty cycling equipment. For example, turning HVAC equipment on for only a few minutes over a one-hour period. This “on” period is rotated from one piece of equipment to another.

If a facility has a high demand charge, different load-shedding strategies can provide substantial savings. Reducing the demand by 20 kW each month, at an average rate, would provide annual savings of about $1,450. If this could be done at 20 facilities, the annual savings from demand-shedding alone would be about $28,900.

Attend any training classes offered to the maintenance and operations staff. Consider videotaping the sessions to provide orientation and training for new staff.