10 Energy Efficiency Tips for Schools and Facility Managers

Academic settings pose a unique set of challenges to facility managers who operate, maintain and manage day-to-day performance of HVAC systems for these facilities. The surging cost of energy in recent years has fueled the growing interest facilities to be more energy efficient.

Schools can significantly reduce their overall cost of owning and operating an HVAC system by incorporating energy efficient equipment. In most cases, the more efficient equipment will be paid back through reduced operating costs in the first year.

Industrial Controls offers you 10 Tips for increasing Energy Efficiency while also keeping IEQ in mind:

1 – Regular Air Conditioning Maintenance

Regular maintenance of air conditioning systems maintains optimal cooling performance and saves energy. The most common causes of degraded performance are:

• Dirty filters and fans;
• Improper belt alignment and adjustment;
• Air leaks in equipment cabinets and ducts;
• Improper air damper operation;
• Dirty condenser and evaporator coils;
• Improper refrigerant charge. 

The replacement of aging systems with energy-efficient retrofits delivers short-term and long-term benefits. An efficient new air conditioning system can reduce your maintenance costs; make classrooms more comfortable, and lower long-term energy costs. You can create a positive domino effect by targeting your most inefficient systems first, and then using the energy savings to target additional capital improvements.

2 – Damper and Actuator Maintenance

One of the most common problems with HVAC systems is improperly operating, or leaking, outside air dampers, which can affect not only energy efficiency but also indoor air quality throughout your facilities. If stuck open, they overload the cooling coil with hot outside air; if stuck closed, they lose the opportunity for free cooling. Cleaning and lubricating moveable surfaces and checking actuator movement and setpoint should be done every three to six months. If this maintenance causes a five-ton compressor to operate only 20 hours less, energy savings can equate to $0.10 per kWh.

3 – Heat Exchange Coil Cleanliness

Dirty condenser and evaporator coils reduce cooling capacity and make the compressor work harder and longer. Cleaning the condenser coil is one of the most cost-effective maintenance steps that can be done on the HVAC systems. A dirty coil that raises condensing temperature from 95° to 105°F cuts cooling capacity 7% and increases power consumption 10%, with a net compressor efficiency reduction of 16%. In a 10-ton unit operating 1000 hours per year this wastes about $120 per year in electricity costs. You can clean the condenser coil in about an hour, resulting in a payback of 2 to 3 months.

A dirty evaporator coil reduces air flow and degrades heat-transfer efficiency. Although the evaporator coil should stay fairly clean with good air filtration, it should be inspected at least once a year and cleaned as required.

4 – Demand-controlled Ventilation

Demand-controlled ventilation improves the energy efficiency of the ventilation system by optimizing fresh air supply based on true need.

Demand-controlled ventilation manipulates an HVAC system to control the amount of outside air being supplied to a space based on occupancy, as measured by the amount of CO2 present in that space. Less energy is consumed because fans only run when outside air is needed.

Learn more about Demand-controlled Ventilation >

5 – Boiler Efficiency Systems

In most climates, the boiler is usually the largest single piece of energy-using equipment in a school building.  Most boilers have old mechanical linkage systems with one “foot-mounted” actuator to position both air and fuel at the same time.  A Linkageless fuel/air controller replaces this single actuator with separate direct-coupled actuators.

The increased accuracy and precision in firing rate control you gain from a Linkageless system can offer fuel savings of up to 10%.

6 – Effective Water Heating Strategy

Set the thermostat at the lowest acceptable temperature, because the hotter the water temperature the faster you lose energy through the pipes and storage tank.  You should also locate water heaters near the point of main use.

You may want to consider the possibility of adding a timer to shut off electric water heaters during periods when the building is unoccupied. These timers also control the hot water recirculation pump. Prices for recirculating system timers range from $40 to $50, and have a payback period of 2 to 5 years.

7 – Energy-Efficient Building Envelope

Increased insulation in the walls and ceiling helps to reduce heat loss and improve comfort. Light-colored exterior walls and white roofs help to reduce cooling loads. These factors also contribute to reducing the size and cost of the HVAC system needed as well as long-term operating and maintenance costs.

8 – Lighting and Electrical Systems

Use of controls in daylit spaces can automatically reduce or increase light levels as needed. Occupancy sensors automatically turn off lights in unoccupied spaces. These options increase construction costs slightly, but pay back that increase in less than one year through energy cost savings.

9 – Remote Energy Monitoring

Identify efficiency opportunities that may have otherwise been missed and verify performance on a regular basis and immediately correct inefficiencies present for an effective way of keeping a building’s long-term energy use on track.

10 – Recommissioning

Studies have shown that continuously monitoring a building’s energy systems can lead to reductions of 10 percent to 15 percent in annual energy bills.  For the typical 100,000 sq. ft. school building, that’s equal to about $14,000 in savings per year! Savings typically come from resetting existing controls to reduce HVAC waste while maintaining or even increasing comfort levels for occupants.

Conclusion

Almost all of the energy efficiency measures discussed here represent good investments. Most will not only save money but will enhance both the aesthetics and the learning environment of your educational facility.