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FROM THE FIELD: “Everything Looked Fine at First Glance”


Molly H. Dee, CEA, LEED GA, WELL AP, CPHC, is a Senior Project Engineer in the commissioning services group of Jaros, Baum & Bolles (JB&B) of New York City. JB&B is a corporate BCxA member whose Director of Commissioning, Ryan Lean, serves on the BCxA International Board of Directors. Molly and Ryan worked on a project in New York City that is a great example of energy management savings – and unintended consequences.

Molly published an article in Buildings magazine, “Energy Savings Plan: Consider Occupant Comfort” in late May addressing systems, building performance, load shedding and other issues around energy management that affected this project (and others). Ryan noted, “Everything looked fine at first glance. When we took a closer look at the building’s energy management program, we noticed a series of shortcuts that, while allowing the building to meet its energy reduction goals, didn’t give much consideration to the impact on occupant comfort or the operation of other building systems.” Read the complete article.

  1. mike bray
    Reply

    Comments from Owners about high energy cost. So we started reviewing the un-occ schedule and OA.
    BAS programmers only do what they are told, so we reviewed the un-occ schedule, with no schedule, modification to schedule and noticed the OA dampers are always open with no C02 control, added return C02 control to each AHUs. If enthalpy is low (30 Btu/ 50% Rh) use OA, and when conditions are not maintain the 1100 PPM range 15 minutes prior to clients arriving to building, close OAD after 15 minutes of client 95% departure of building.
    Lighting control with occ and un-occ sensors is still a challenge, the Lighting vendors have NOT been helpful with the Owners.
    As the Gate Keeper we stand guard

    • Molly Dee
      Reply

      Mike, thanks for the comment. I do often find that BAS contractors do their best to implement everything the client asks for, even if it may negatively impact the building systems or the day-to-day building occupants. This is especially true when they have a service contract with the building and are working to maintain a good relationship with the building management and operations staff. While this is understandable, and some might argue good customer service, it can cause all sorts of unforeseen issues.

      The good news: Once we Cx people point out these issues, more often than not I find the Client to be pretty receptive to better more effective strategies.

  2. Lyn Gomes
    Reply

    How did the building implement DR off power consumption? And how was that setpoint established?
    We have an MEP firm here in CA that insists on writing their DR sequence this way.
    Unfortunately, they don’t include meters, integration, or a setpoint in their sequence. As a result, it never gets implemented.
    I’ve suggested other ways they can do it, but they don’t seem to get it. So I’m stuck with meeting them where they’re at. (Which is probably the best option anyway, even if it is at the expense of my ego. Hahaha)

  3. Molly Dee
    Reply

    Hi Lyn, I don’t know how the case-study building determined their specific demand response threshold consumption setpoint. I know the facility management team had a group that did a fair amount of utility bill analysis, so if I had to hazard a guess, I’d say the threshold number was determined via those means.

    In terms of implementation, the facility had their BMS/BAS service provider create a brand new program, which was uploaded into the controllers of each piece of equipment affected by DR. The provider also created a “front-end” interface to show where consumption was in real-time as compared to the threshold limit.

  4. Neil Caswell
    Reply

    I know of one building which was lauded for its energy reductions – and even won prizes for it. When I queried the design team I discovered that they were completely switching off alternate zone AHU’s fans on a regular basis. Their view was that no-one would notice if it was only for an hour or so. Load shedding by another route!

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