I’d like to end the fiasco that was 2020 on a hopeful note and talk about building systems operation after the pandemic. Although we are not at that milestone yet, this is a follow-up to my November 2020 column, “Retro-Commissioning for the Pandemic.”
As recommended last month, building owners should have a current facilities requirements (CFR) document explaining the operating intentions for all building systems. With respect to HVAC and any COVID-19 strategies implemented during the pandemic, the CFR should be clear on which strategies were intended to be permanent and which were intended to be temporary. The temporary strategies will be reversed after the pandemic, but to what new state will the HVAC system be set?
When a building owner determines it’s time to return to “normal,” the CFR should be updated to reflect this new normal, which will likely differ from the pre-pandemic normal. Many work places will have a lower average occupant load as employees and employers take advantage of technologies and processes that support working from home.
How will building owners handle this from a space/real estate perspective? Will they downsize their facilities and maintain the old relatively high-occupant density in smaller spaces, or will they stay in their same buildings and simply have lower people-per-square-foot counts? Regardless of the decisions made, the changes will not happen overnight, and they are apt to be incremental.
Building operators will be challenged to run their HVAC systems in the most energy-efficient manner while supporting evolving space usage decisions. That might mean annual (or more frequent) evaluation and resetting of operating hours and minimum outside air ventilation rates. Such ventilation analysis and adjustments should involve a professional engineer and a testing, adjusting, and balancing (TAB) contractor. The regular investment in such outside consultants is not typically in anyone’s operating budget, but they should more than pay for themselves in energy savings by right-sizing the ventilation system, especially in severe climate zones.
Another option would be to invest in demand-ventilation controls and have the HVAC systems automatically adjust their outside air intake quantities based on carbon dioxide concentrations. This could have a relatively high implementation cost, but it would have the benefit of being hands-off in the future, other than regular sensor calibration and damper operation checks. These checks could be performed by in-house technicians.
Regardless of the strategies selected, the post-pandemic period will require building operators to be in a nearly continuous retro-commissioning mindset as building needs change and energy conservation becomes a driving force again.