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Peter McPhee

21 Sep, 18 tweets, 6 min read

@MassCEC

Is it possible to electrify LARGE buildings? Even in a cold state? What about in a big city? How about a small town?? @MassCEC put VRF heat pumps to the test. 110 commercial buildings later, answers to your most pressing questions.

ANOTHER THREAD:

Executive Summary: The technology, industry, and market exist today for VRF heat pumps in commercial buildings. They can offset all heating load in a cold climate and can be configured for small to VERY large commercial buildings.

@cafeaj

What the heck is VRF and why is it important?? My talented colleague @cafeaj explains, along with case studies and pretty pictures (masscec.com/blog/2021/09/1…).

Takeaway 1: VRF is a viable, broadly applicable low-carbon heating solution for commercial buildings. Market, industry, technology are strong. Awareness is not (both for building owners and industry).

Takeaway 2: Operational cost-effectiveness of heat pumps is enhanced by greater relative cooling load of comm bldgs, as VRF is typically more efficient than traditional AC. However, winter demand can contribute to higher costs. Cost-effectiveness is building specific.

@RockyMtnInst

#3: Upfront cost-effectiveness varies, but ductless VRF can sometimes be lowest upfront cost solution (includes heating, cooling, & distribution!). Similar takeaways to @RockyMtnInst analysis for residential new construction (Boston) (rmi.org/all-electric-n…)

#3a: there are ancillary cost benefits from VRF, including
•Heat recovery: a VRF system can remove heat from a server room and put it near the exterior of the building. Or move heat out of the hot conference room to that cold office.

•reducing building floor heights (for NC) because you don’t need to fit ductwork in a dropped ceiling. This adds up in value when getting an additional floor to a building in downtown Boston!

#4: VRF offers enhanced occupant comfort, as
•zoning is greatly improved (room by room) and
•systems can operate in simultaneous heating and cooling, moving heat from 1 part of building to another (remember sitting by window vs. by copy machine?)

Takeaway 5: VRF is (relatively) new and complex. Many of the same teachers for residential heat pumps apply to commercial heat pumps:
a. sizing and design require more careful attention than fossil fuel systems,

b. having a well-performing building envelope is a win-win, and
c. most contractors could benefit from enhanced training.

Conclusions: We have a climate-friendly solution to heating commercial buildings, but there’s still work to do with building awareness, training the industry, and scale up implementation.