B4.11 Grid-connected appliances *
Require smart appliances in new construction, especially water heaters that control timing of demand.
WAC 51-56-0501.1.2 requires heat pump water heaters manufactured after January 1, 2021 and other electric storage water heaters manufactured after January 1st, 2022 to include a standard two way communications interface for remote energy management.
Lazar’s Teaching the Duck to Fly (2nd edition) provides a good overview of the large potential reductions in costs and emissions available through shifting demand from peak periods (when the emissions from marginal power sources are generally higher) by using grid-connected appliances, especially water heaters and air conditioners, and a number of other clever methods.