Which of the following is a strategy to reduce a building's operational energy use?

• A. Improve insulation and airtightness, deploy high-efficiency HVAC and lighting, and optimize equipment and controls
• B. Increase glazing area without shading
• C. Use older, less efficient equipment
• D. Disable demand controls and monitoring

Answer: (A)

Reducing a building's operational energy use comes from lowering the energy needed to run it day to day. Improving insulation and airtightness cuts heat loss and unwanted air leakage, so the building doesn’t have to work as hard to heat in winter or cool in summer. Pairing this with high-efficiency HVAC and lighting reduces the amount of energy those systems consume when they’re running. And optimizing equipment and controls makes sure everything operates only when needed, at the right times, and at the right settings, avoiding waste from unnecessary operation or poor scheduling. This combination tackles both the demand side (how much energy the building needs to maintain comfort) and the efficiency of the equipment that delivers that energy.

Increasing glazing area without shading boosts solar heat gain, which can dramatically increase cooling loads and energy use. Using older, less efficient equipment naturally consumes more energy. Disabling demand controls and monitoring removes the ability to adjust operation based on occupancy, daylight, or other conditions, leading to wasted energy.