For decades, policymakers have viewed appliances that are fueled 'on site' by natural gas as environmentally preferable to electric appliances that rely on electricity generated at an off-site 'source,' such as at a coal or natural gas power plant. Several trends in energy generation and end-use technology, however, are changing the environmental value of using electric appliances to produce heat and hot water in buildings, requiring a more systems-based approach to energy efficiency tools and revisions to the methodology for calculating 'source' energy metrics.
Dennis, K. (2015). Environmentally Beneficial Electrification: Electricity as the End-Use Option. Electricity Journal, 28(9), 100–112. https://doi.org/10.1016/j.tej.2015.09.019