Based on these findings, the RTF analysts proposed estimates of 25% for office space types and 35% for retail space types.
The 2014 Commercial Building Stock Assessment (CBSA) lighting inventory was used to determine the distribution of space types within each building type. Each space type was categorized as similar to an office space, similar to a retail space, or neither. Demand response potentials of 25%, 35%, and 0%, respectively, were applied to these spaces, and a floor-space weighted average of the potentials was calculated. This average is considered the building-level lighting load reduction percentage for each building type in the CBSA.
To support the research, RTF analysts discussed this DR mechanism with DR program implementers, lighting engineers, the author of a statewide lighting DR potential study, and the RTF Demand Response Subcommittee. These discussions validated the focus on office and retail spaces but also revealed program skepticism of the practical DR potential for commercial lighting.
DR program implementers did not see much participation from lighting loads currently or interest in them going forward. Typically, HVAC is a larger opportunity in a building, is simpler to control, and temporary HVAC reductions are noticed less than lighting reductions. As lighting systems become more efficient, and regularly dimmed to low levels in daylit and unoccupied times, the opportunity for demand response is reduced.