This appendix to the residential compliance manual addresses the demand responsive (DR) control requirements in the 2022 Building Energy Efficiency Standards (Energy Standards).
Demand response is an increasingly important function of buildings as distributed energy resources become more common and customers have access to time of use electricity rates and incentive programs designed to encourage demand side optimization. Demand response occurs on a range of timescales, from seconds to seasons, and represents any demand change in response to grid or economic needs. In addition to current time of use electricity rates, utilities in the future will likely connect electricity costs to high frequency fluctuations in both the supply and demand for electricity. Appropriate demand responsive controls allow building operators to maintain the quality of services a building provides and reduce the total cost of energy by automating a building’s response to changes in electricity rates.
The following definitions from §100.1 are relevant to the DR control requirements:
Demand response is short-term changes in electricity usage by end-use customers, from their normal consumption patterns. Demand response may be in response to:
a. Changes in the price of electricity; or
b. Participation in programs or services designed to modify electricity use.
i. In response to wholesale market prices.
ii. When system reliability is jeopardized.
Demand response period is a period of time during which electricity loads are modified in response to a demand response signal.
Demand response signal is a signal that indicates a price or a request to modify electricity consumption for a limited time period.
Demand responsive control is an automatic control that is capable of receiving and automatically responding to a demand response signal.
The DR control requirements ensure that the building is DR capable (i.e., capable of responding to a DR signal). The decision to employ demand response is up to the building owner or manager, in coordination with their utility company and/or a governing authority. A building that is capable of receiving and responding to a demand response signal is sufficient to meet the requirements of the Energy Standards. DR-capable is described as follows:
DR-capable: A building is capable of DR when the building has loads that can be curtailed, DR controls are installed, and the controls have been programed/configured so the test control strategy that is defined in the building code can be deployed (note: the DR controls can be programmed with additional control strategies).
DR-enabled: A building’s DR is enabled when the connection between the entity that sends the DR Signal and the DR control in the building has been tested and communications have been allowed or “enabled”.
DR-enrolled: A building is enrolled when the building owner/occupant has enrolled in a DR program (note: this may include updating the settings or programming of the DR controls to better match the terms of the program).
The requirements for DR controls only apply if the controls are used to comply with the building standards (i.e., DR thermostats or a heat pump water heater). If DR control are installed voluntarily and do not contribute to compliance with minimum code requirements, they do not need to adhere to requirements in Title 24, Part 6.
For residential dwellings, DR controls are only required as a part of specific Exceptions to HVAC and Solar Ready requirements.