Fuel-switching efforts by Vermont utilities have been driven by the state’s 2015 Renewable Energy Standard (RES, Act 56), which addresses building electrification and comprises three components or tiers. While Tier I and II of the RES address renewable energy requirements, Tier III requires utilities to reduce customers’ fossil fuel use through either electrification, efficiency, fuel switching, or storage. This requirement is 2% of a utility’s annual sales starting in 2017 and increasing by 0.67% annually, reaching 12% in 2032.
Additionally, Public Service Board Docket 8550 provides rules and eligibility criteria for allowable programs under Tier III. These include: 1) a net reduction in fossil fuel and GHG emissions; 2) lowest present value lifecycle cost; and 3) utility cost less than applicable RPS alternative compliance payment (see p. 70 of the Order Implementing the RES, pursuant to Section 8005(a)(3)(C) of state code).