K-12 schools

Heating, ventilation, and air conditioning (HVAC) systems, lighting, and plug loads (such as computers and kitchen equipment) are the major energy consumers in K-12 schools. The specific breakdown can vary based on climate and the age of the facility, but HVAC typically represents the largest portion of energy usage, followed by lighting, and then plug loads.

EBCx is a systematic process of optimizing an existing building's systems to ensure they operate as intended. This involves verifying that HVAC, lighting, and other energy-using systems are functioning efficiently, are properly calibrated, and that operational schedules align with building usage. EBCx often identifies low-cost or no-cost improvements that can immediately reduce energy consumption by optimizing existing equipment before making significant capital investments.

Upgrading from older, less efficient lighting (like T12 fluorescent lamps with magnetic ballasts) to more efficient technologies such as T8 or T5 lamps with electronic ballasts or LED fixtures can significantly reduce energy consumption. In addition, using occupancy sensors, photosensors, and dimming controls can further reduce lighting energy use by turning lights off or dimming them when areas are unoccupied or when sufficient daylight is available. Daylighting strategies, using features like light shelves, skylights, and tubular daylighting devices, can also reduce reliance on artificial lighting.

Reducing plug loads involves a combination of behavioral changes, policy implementation, and equipment upgrades. This includes ensuring equipment is turned off when not in use, utilizing vending machine controls to reduce energy during off-hours, using ENERGY STAR certified equipment where applicable, implementing a policy regarding personal powered devices, and conducting an energy awareness program to engage staff and students in energy conservation. Replacing older transformers with energy-efficient models and upgrading kitchen equipment can also have a big impact.

Improving air distribution systems includes optimizing ventilation rates, ensuring proper air flow by balancing the system, using demand-controlled ventilation (DCV) based on occupancy, and implementing variable-air-volume (VAV) systems, as opposed to constant volume systems. This often entails right-sizing fans and adding variable speed drives (VSDs) to pumps and fans. Improving air filtration with electronic air cleaners and recovering heat from exhaust air streams can also contribute to efficiency improvements. For older mixing ventilation systems, switching to dedicated outdoor air systems (DOAS) or displacement ventilation can save significant energy.

Significant savings can be achieved by replacing or right-sizing existing heating and cooling systems with more efficient models. This may involve replacing standard efficiency pumps with right-sized, efficient pumps and adding VSDs to pumps and chillers. Heat pumps can be used in most Canadian climate zones with temperatures as low as -10°C, while cold-climate heat pumps are effective down to -30°C. For heating, replacing older boilers with condensing or modulating boilers and addressing issues with flow-restricting valves. For cooling, water-side economizers should be implemented, where possible, to use free cooling via the cooling towers, instead of relying on the chillers.

M&V is a critical step in ensuring that energy efficiency upgrades are actually achieving the projected savings. It involves developing a plan, typically using the International Performance Measurement and Verification Protocol (IPMVP), to measure energy consumption before and after the implementation of energy conservation measures (ECMs). M&V can include detailed utility data analysis (whole building), or spot measurements to verify performance of individual components. M&V plans should define the measurement boundary and monitoring equipment used.

O&M programs ensure that energy systems remain efficient over time. This includes regular system checks, calibration of building automation system (BAS) sensors, fixing issues like missing pipe insulation, and preventative maintenance on HVAC equipment and other energy using components. It emphasizes a proactive approach to energy management, addressing system inefficiencies before they lead to energy waste. Continuous improvement in operations and maintenance is essential to maintain the gains achieved through energy retrofits.