In a new whitepaper published by NYSERDA, E3 provided technical support and analysis to update greenhouse gas emissions factors for electricity delivered in New York. Greenhouse gas emission factors measure the amount of greenhouse gases (GHGs) produced per unit of energy; they are important for accurately measuring GHG emissions associated with a given energy mix and therefore necessary to evaluate progress towards meeting the state’s climate goals. New York’s passage of the Climate Leadership and Community Protection Act (Climate Act) required an update to the state’s emission factor because of the decarbonization initiatives in the Climate Act. E3’s analysis contributed to the development of new emissions factors, replacing the previous static statewide marginal emission factor with new emission factors will that allow New York to better estimate greenhouse gas emissions from electricity use in future years as the state’s grid changes and becomes cleaner.
E3’s contributions to the study included both proposing a new methodology for calculating emissions factors and then calculating emissions factors using the recommended method. E3 reviewed methodologies for calculating emission factors for grid electricity, looking for a methodology that would support the guiding principles of a robust methodology while balancing complexity with overall usefulness and flexibility. E3 recommended use of the Implied Marginal Heat Rate method, using projected electricity prices prepared by Siemens from NYSERDA’s New York Power Grid Study. E3 then calculated emission factors using the recommended method. The new emission factors are published in a spreadsheet database and include: short-run marginal emission factors, long-run marginal emission factors, and annual average emission factors. Emission factors are provided for CO2, CH4, and N2O and also include upstream emissions for each, an improvement on the old factor that only represented CO2.
These new emission factors will allow New York to better estimate greenhouse gas emissions from electricity use in future years as the state’s grid changes and becomes cleaner. The emission factors also include upstream emissions to more fully represent the full fuel cycle for electricity production. The creation of month-hour emission factors will allow for analysis that will reflect time of day and season variations across the year – which is a big improvement on the previous static factor. The new inclusion of long-run marginal emission factors also allows for the state to calculate long-term load impacts that result in structural changes to the generation portfolio (for example, rebalancing of the electricity supply to meet the Clean Energy Standard).
An E3 project team including Christa Heavey, Hadiza Felicien, and Kush Patel supported NYSERDA on the development of the new emissions factors and writing the white paper. E3 would also like to acknowledge the contribution of Siemens and the New York Power Grid Study for modeling included in the calculations.