Building and energy managers sometimes focus on energy-saving strategies to the point that occupants' comfort is sacrificed. But through careful planning and the right tools, building operators can achieve energy benchmarking goals and still keep customers, employees, and other occupants safe and comfortable.
Energy Savings and Occupant Comfort
To address the issue of energy savings versus comfort, we must first understand how the two variables are correlated. This has been established with the Acceptability Index Value (AIV) or the Energy Utilization Index (EUI) ratio, which measures energy usage per the square footage of a building. The EUI is used to "evaluate the effectiveness of energy use to achieve a specified percentage of occupant acceptability."
These metrics are broken down into specific variables and include:
- Electrical power
- Moisture control
- Ingress and egress control
With this data, energy usage can be adjusted to the correct parameters to meet quality comfort levels.
Building Automation Systems and Occupant Comfort
Energy Management Systems (EMS) allow building operators to view energy consumption and look for cost savings opportunities, however, they don’t consider how these strategies might affect building comfort. When coupled with Building Automation Systems (BAS), managers can fine-tune these strategies while maintaining healthy, comfortable environments that help the building’s occupants do their best work.
To do this requires installing controls on HVAC and lighting systems so they can be both manipulated remotely and return system information vital to energy savings and comfort. For example, a cycling fan on an RTU can be seen on a BAS if the temperature is not meeting the space setpoints. With this level of information, a building operator can repair the unit, saving energy when the unit is operating at its optimized state and providing better cooling at lower energy consumption.
Strategies for Comfort Focused Energy Efficiency in Buildings
Energy efficiency contributes to optimal occupant health and comfort with the right strategies and tools in place. With a whole-building approach, design can bring elements such as natural daylighting and LED lights that not only reduce energy costs but improve occupant comfort. You may also consider some of the following:
- Building Commissioning - Energy-efficient whole-building design is essential to reducing energy costs. But implementing energy-saving strategies as the design intended is building commissioning - testing building systems to verify they meet design conditions. Commissioning provides value by adjusting and fine-tuning HVAC and lighting systems to result in optimal energy savings and occupant comfort.
- High-Efficiency Lighting and Control Systems - LED lighting is becoming standard in commercial buildings and can drastically reduce energy costs. It also produces less heat than fluorescent light, keeping the temperature down in brightly lit spaces.
- Individual occupant controls - Two people can be sitting in the same room, and one of them is too hot, the other too cold. When it comes to optimal temperature controls within a few degrees, comfort levels can be subjective. Individual space controls can mitigate the issue. When spaces are unoccupied, sensors can set individual space temperatures up or down and turn off lighting to reduce costs.
Whole Building Efficiency and Well Being
A healthy building is an efficient building. By considering the effects of energy-saving methods on occupants and adjusting to meet their needs, a building can achieve its desired intent and long term operational goals. An analysis of HVAC systems and controls, lighting systems and controls, building orientation, views and daylighting, and overall aesthetic can all play a role and must be considered by building operators. With systems and protocols in place, efficiency and comfort can both be achieved.