In countries such as the US, many building owners and managers are facing, perhaps for the first time, low to zero occupancy. This may also soon be true for Singapore, this is an unprecedented moment and many questions need answering. Question like:
- How can I make sure my building operates efficiently during low occupancy?
- What systems should I focus on adjusting during low occupancy?
- When this is over, how can I make sure my building will return properly to normal operations in the future?
Schneider Electric offers answers to these questions by laying out 10 best practices on energy efficiency, safety, and reliability for low-occupancy buildings.
Important first steps
Before beginning, it is recommended you reach out to your service partner, if you have one. This partner should be able to help you complete much of the work laid out in this guide, either remotely or on-site.
If you do not have a service partner, Schneider Electric has offered some tips on how your own team can get started.
Checklist: 10 best practices for efficient low-occupancy buildings
- Establish your scope. First, take stock of your major HVAC and building automation assets, including chillers, air handlers, boilers, and so on. These are the key components that will be drawing energy and managing environmental conditions.
- Determine your system architecture. Find out which assets are connected to your building management system (BMS) and which assets are standalone, requiring manual control. Understanding the full scope and architecture allows you to be thorough and efficient in making these adjustments.
- Record your changes so you don’t forget them. Before you make these adjustments, be sure you record both normal settings and new settings. If you lose track of this information, you may struggle to return your building to normal operations, which could create issues with occupant comfort, HVAC performance, and safety.
- Account for regional differences. An 80 °F setpoint may turn off AC systems in Florida, as intended, but it could turn on heating systems in your New England facility. This may seem obvious, but during these confusing times, it can be easily overlooked.
- Focus on deep efficiency. Consider the difference between your typical low-occupancy setpoint (i.e., for weekends) and “deep” low-occupancy setpoints. If on weekends you typically adjust to ±5 °F off the setpoint, you might consider a deeper ±10 °F change during this time.
- Accommodate remaining staff. Remaining on-site staff (e.g., security and maintenance) will still need a comfortable climate, but will not likely be using conference rooms, gyms, or cafeterias. Lighting systems should also be adjusted accordingly. Depending on your climate, you can adjust window blinds to reduce heating or cooling demand.
- Factor in your new BTU loads. It’s not just a matter of turning the thermostat down a few degrees. You should also factor in lower BTU loads (i.e., heat generated by occupants, their computers, etc.), which will also change. Your HVAC system was likely designed for higher BTU loads.
- Modify your ventilation and economizer systems. During low occupancy, you have more flexibility in your temperature ranges, so you can turn down ventilation and rely more on outside air cooling via economizers. Doing so will reduce energy demand.
- Keep humidity in check. If you’re changing your temperature setpoints, don’t forget about humidity. Mold and moisture can become a problem if indoor dew points are not properly calibrated. ASHRAE recommends keeping relative humidity levels below 65 percent.
- Adjust fans, fridges, and freezers. Commercial kitchens and labs have exhaust and make-up fans that often run 24/7, but likely won’t be needed during this time. And if you no longer need refrigerators or freezers to store food, shut them down.
Going beyond the low-hanging fruit
This 10-part list was just the basics of what you can do to drive efficiency in buildings during low occupancy. Every building is different and will have unique savings opportunities.
For a deeper dive, There are more tips and details here.
If you’re unsure about getting this work done yourself, Schneider Electric’s field service engineers can help, whether face-to-face or remotely. Their service hotline is at +65 6484 7877 or you can contact your local account representative to get started.