Commercial Connected Thermostats Specification Discussion

Discussion Scope:

The RTF has asked staff/CAT to develop a measure for connected thermostats in commercial buildings. Since there are many potential measures that could reasonably be called “Commercial Connected Thermostats,” the CAT sought additional direction at October RTF meeting. This thread is a continuation of that discussion. Our primary objective is to obtain feedback on the type(s) of RTF Commercial Connected T-stat measure(s) that would be useful to the region.

To the extent possible, we hope to keep the present discussion focused on the broad shape of the measure(s) rather than the details of how the measure(s) should be constructed. After we get direction on the type(s) of measure(s) to pursue, we can start working to resolve things like first-year savings, delivery verification, persistence, and research strategy.

Assumptions:

Custom evaluations may be more appropriate for complicated multi-zone HVAC systems or Energy Management Systems that integrate control of HVAC, lighting, and other systems. Developing a new UES measure would not change this. The CAT’s current assumption is that we are looking for a UES measure that applies to relatively simple systems:

Nonresidential buildings (excluding hotels)
T-Stat must control a single HVAC system having its own supply fan and serving a distinct zone

In addition, the CAT currently assumes:

This will be a Planning measure, and the UES will be uncertain until we’ve met the objectives outlined in the research strategy (to be written once we know what the measure is)
The Planning UES and the research strategy will seek to reflect the measure specification (e.g., if the measure spec. makes no requirements on the pre-existing thermostat settings, then the UES should reflect this)

Below, we roughly sketch three kinds of measures that have been suggested at various stages of this process. We’ve tried to make a small number of fairly specific suggestions, rather than an exhaustive list which could make it difficult to identify areas of agreement among comments.

Measure Version 1

UES measure based on installation of physical thermostat, no requirements regarding thermostat settings.

Efficient thermostat must meet the following requirements (pick one):

Temperature programmability
Temperature programmability and web-connectable
Temperature programmability and fan programmability
Temperature programmability, fan programmability, and web-connectable

Eligibility does does not include requirement that pre-existing thermostat settings failed to meet some requirement from the previous item.

Measure Version 2

UES measure based entirely on requirements regarding thermostat settings.

Measure would not require thermostat delivery
Would need to spell out what constitutes minimally efficient settings with respect to temperature set-backs and fan programming
Eligibility does does not include requirement that pre-existing thermostat settings failed to meet efficient requirements
Delivery verification would include confirmation that post-case thermostat settings are sufficiently efficient and that pre-case settings were not
Verification could be accomplished via web interface, service contractors, or physical site inspection

Measure Version 3

UES measure based on installation of physical thermostat and specific requirements regarding thermostat settings

Efficient thermostat must meet the following requirements: Temperature programmability, fan programmability, and web-connectable
Would need to spell out what constitutes minimally efficient settings with respect to temperature set-backs and fan programming
Eligibility includes a requirement that pre-existing thermostat settings failed to meet efficient requirements
Delivery verification would include confirmation that post-case thermostat settings are sufficiently efficient and that pre-case settings were not
Verification could be accomplished via web interface, service contractors, or physical site inspection

Feedback on Measure Options

After reviewing the measures options above, please provide your feedback on which best match what potential measures your utility is interested in. We are not looking for a single measure to solve all problems. Instead we are looking for a specific, coherent, measure(s) that would be useful for the region and which can make sense as an RTF UES.

Have questions?