「英中对照」NEMA高管提出B级楼宇分阶段节能改造路径以控制成本

Operators of Class B buildings who stage upgrades over time can make their buildings more energy efficient without having to ask owners to put up a lot of money, according to executives at the National Electrical Manufacturers Association.

By starting with the savings from relatively low-cost upgrades, like a new occupancy-based LED lighting system, operators create a starting point for funding a capital stack that they can apply in stages to more impactful upgrades, Todd Sims, NEMA’s senior director of regulatory and industry affairs, told Facilities Dive in an interview. 

“Start with low hanging fruit,” Sims said, “then implement a building or energy management system and take the savings from that and add that to the capital stack to make more capital-intensive improvements.”

Staging improvements in this way enables each level of upgrades to pay for the next one, he said.

The challenge isn’t with Class A buildings, Sims said. A third of these are already LEED certified for efficiency, and if they’re not, finding ways to pay for upgrades is less pressing for them than for lower-tier buildings because of the rents they can charge, he said. “They can largely afford many of the upgrades they want to make,” he said. 

The challenge is concentrated in lower-tier buildings. “Something like 80% of the buildings that will be around in 100 years have already been built, and the preponderance of those are Class B buildings,” he said. 

In addition to lighting, initial upgrades might include energy monitoring and submetering, which enable owners to bill energy costs at the tenant level and also generate data for tracking building performance through Energy Star data feeds. Tracking performance in turn can help buildings meet reporting requirements if they’re in a state or municipality that requires owners to meet building performance standards. 

A second group of upgrades might include adding variable frequency drives to air handlers, pumps and fans. The drives reduce energy use by adjusting the amount of power that’s needed based on what the systems are being used for rather than by dampening the motor, an inefficient operation that conventional drives tend to use, according to Zack Valdez, NEMA senior director of regulatory and industry affairs.

“If you think of a [typical] motor, it’s only got two speeds — 0 or 100 — and to go to 75%, you use some sort of dampener,” Valdez told Facilities Dive. “A variable frequency drive says, ‘I’m going to cut the energy to 70% for that motor and just give it 70% of the energy that it needs,’ so you’re saving roughly 30% of the energy.”

Technology for these drives has been around for years, and the kinds of motors that can benefit from the drives are ubiquitous in building systems and industrial processes, Valdez said. 

“What pushes your AC or your heat through your system, what pushes water through these buildings, whatever heats something probably has a motor that [can] incorporate it,” he said.

But many facilities managers remain unfamiliar with the technology, and building owner leadership, if they know of it, might be reluctant to spend money on it despite the savings it can produce, he said. 

“If finance is writing the check, they’re concerned about the next quarter, not four years from now,” he said. 

NEMA tested almost 20 types of systems and, in an industrial context, the cost of the drives in some cases can be recouped in fewer than three years, he said. 

A third group of upgrades might include improvements to the electrical system, including panel upgrades for EV-ready and renewable-ready infrastructure, the addition of supplemental heating, like dedicated-zone heating for vestibules, and adding a building management system if the facility doesn’t already have one. 

A last group might include adding back-up power or storage, enabling the building to shave its peak energy use and enroll in a demand-response program if one’s available.   

“There’s a tremendous amount of opportunity there,” Sims said. “Class B buildings can do it on their own if they [can] stagger the upgrades.”