On September 9, 2019, Mayor Miro Weinberger, Burlington Electric Department (BED) General Manager Darren Springer, and others publicly released the City’s Net Zero Energy Roadmap. The Roadmap announced a goal of reaching Net Zero Energy by 2030. Net Zero is commonly defined with reference to “greenhouse gases.” An accepted definition is: “Net zero refers to a state in which the greenhouse gases going into the atmosphere are balanced by removal out of the atmosphere.” https://netzeroclimate.org/what-is-net-zero/ However, rather than define Net Zero with reference to greenhouse gas emissions, the City of Burlington’s Roadmap defines Net Zero with reference to elimination of fossil fuel use. “The City’s Net Zero Energy by 2030 (NZE by 2030) goal is defined as reducing and eventually eliminating fossil fuel use from the heating and ground transportation sectors.” Roadmap 1.
This is a perverse definition of Net Zero. It allows substitution of non-fossil fuel types of energy for fossil fuel energy to count toward meeting the Net Zero goal regardless of the non-fossil fuel energy’s greenhouse gas emissions. Substituting non-fossil fuel energy for fossil fuel energy counts toward achieving the Net Zero Energy Goal, even if it results in an increase in greenhouse gas emissions. This is precisely what happens when heating systems fueled by biomass, biofuels or “renewable” natural gas are substituted for fossil fuel heating systems, which in Burlington are primarily natural gas systems. When these types of “renewable” energy are substituted for natural gas, greenhouse gas emissions increase- yet the City claims credit toward meeting its Net Zero goal.
The City declared its Net Zero goal to be “the most ambitious climate goal established by any community in the United States to date.”
The Net Zero Energy Road Map announced pursuit of four pathways toward achieving the Net Zero goal, two of which relate to heating of buildings:
Efficient Electric Buildings: Efficient electric buildings, including comprehensive weatherization and electrification of space and water heating, represents the largest opportunity, with the potential to realize 60 percent of total fossil fuel reductions; and
District Energy: Implementing a District Energy system could represent 15 percent of total fossil fuel reductions, and would help meet the space and water heating needs of high-load buildings that otherwise would be more difficult to heat with electric heat pump systems alone.
District Energy refers to retrofitting the McNeil Generating Station, which primarily burns wood, in order to collect steam and sending the steam by pipe to certain users for heating. A number of iterations of the District Energy Plan have been pursued over the years and have proven economically unviable. The City’s current District Energy Plan is to provide steam heat to the University of Vermont Medical Center, the UVM campus and the Intervale. The District Energy Plan is a pillar of the Roadmap even though wood burned in the McNeil Generating Station emits more greenhouse gases per unit of energy produced than burning gas or any other fossil fuel, including coal, and pursuing the District Energy Plan will increase greenhouse gas emissions.
The Roadmap also sanctions limited use of “renewable” natural gas. “Renewable natural gas could be used to offset a small proportion of natural gas use in buildings where heat pumps cannot supply the heating needs for the entire building. However, supply will be limited, and the price could be high so this strategy should be deployed sparingly.” Roadmap 17.
The Roadmap contains a brief reference sanctioning biomass heating systems, which include wood and pellet stoves. “While biomass heating systems were not modeled, biomass could also provide a clean and efficient heating solution for some homes and businesses.”
The Roadmap does not discuss liquid biofuels.