ASHRAE standard 90.1’s goal to progressively reduce building energy usage has resulted in the steady introduction of additional requirements to each new version of the standard. In more recent versions, added requirements for the use of DDC controls along with the use of control sequences such as economizers (air and waterside, and most recently, with “self-diagnostic” capabilities), optimum start, demand-controlled ventilation, reset of duct/pipe pressure setpoints for variable volume systems, single-zone AHUs, and the fan-powered sections of VAV boxes can no longer be constant volume, etc.
However, through the 2013 version, these have essentially applied to only “new” construction. Further, many of these “sequence” requirements have started to become standard practice for building design and construction. Therefore, the effect on the controls market has been minimal (or even for the worst given its possible negative effect on controls contractor’s profit margins).
The requirement to upgrade these controls could finally be the “nail in the coffin” for a major source of building discomfort, increased energy consumption, limited building operating information, etc.
But the latest 2016 version of 90.1 has expanded its scope to include remodels/additions of existing buildings. The possible effect of this on the demand for DDC controls (and BAS) could be enormous given the number of existing buildings that don’t meet the more recent controls requirements of 90.1.
Let’s look at the two possibly defining examples of the controls impact from 90.1’s expanded scope to include existing buildings.
I am not aware of any data regarding the quantity of pneumatic VAV box controls that are still in use. However, I would guess it to be quite many … as in perhaps millions. The requirement to upgrade these controls could finally be the “nail in the coffin” for a major source of building discomfort, increased energy consumption, limited building operating information, etc.
The actual interpretation and enforcement of what work constitutes “remodels/additions” (i.e., will every “tenant finish” project big or small be included) will determine whether pneumatic VAV box controls will continue to be replaced slowly or if the effect will be to exponentially increase the replacement work (along with the demand for DDC VAV box controls). I hope it is the latter.
Single Zone RTUs
Packaged single-zone RTUs (with constant volume fan operation and air-cooled DX) are one of the last major impediments to energy efficiency improvements in existing light commercial buildings. Here, too, there are also probably millions of instances of this type of equipment still in use. Of course, merely changing an existing RTU to VAV is not the only (or most-important) step needed to improve their energy efficiency (i.e., there’s probably more to be gained by improving the DX system). Further, it may not always be possible to merely change an existing RTU to VAV due to a DX system’s inability to handle the reduced air flows. Finally, the added requirement for properly-operating and self-diagnosing economizers only ups the ante.
So it is possible that 90.1’s “no more constant volume” requirements could lead to not only an explosion in the need for more-advanced RTU DDC controls but in the wholesale replacement of RTUs using “old” technology?
Of course, the extent of this potential controls “explosion” will depend on:
How 90.1 is adopted by local code authorities (i.e., directly or indirectly and with different language/interpretations via the IECC or Title 24);
When it will be adopted (i.e., widespread adoption could be spread out over many years);
How diligently it will be enforced, which is always going to be an issue for something like control sequences that are difficult to “see.”
But no matter how this all unfolds, I see this change to 90.1 to be great news for energy-efficiency in general and the DDC controls market specifically.