
August 12, 2021
Carbon Accounting Mechanics: How Transitioning to an Electrified Fleet Reduces GHG Emissions
By Mark Gooden, Transportation Electrification Analyst, and Erin Williamson, Manager, Energy & Sustainability Strategy

In the previous installment of our Transportation Electrification Blog Series, we covered all the electric vehicle terminology you need to know to speak like an EV pro. In our fourth installment, we will be discussing the categories of greenhouse gas emissions and how transitioning from internal combustion engine vehicles to electric vehicles can help eliminate these emissions.
Reducing greenhouse gas (GHG) emissions is critical for combating anthropogenic climate change. As companies plan for and start to decarbonize, plug-in electric vehicles (EVs) have emerged as a feasible solution to reduce emissions in the transportation sector. Unlike internal combustion engine (ICE) vehicles, fully battery electric vehicles produce zero tailpipe emissions during use. This shift in vehicle technology can drastically reduce a company’s environmental footprint when applied at a fleet scale.
Understanding Scope 1, Scope 2, and Scope 3 GHG Emissions
As organizations begin to track and account for carbon reduction, the GHG Protocol is a measurement tool that is used to categorize and take inventory of emissions. These are divided into three distinct categories, as seen in the graphic below.

Scope 1 emissions are direct GHG emissions from sources controlled or owned by an organization.
Scope 2 emissions are indirect GHG emissions associated with the purchase of electricity, steam, heat, or cooling.
Scope 3 emissions result from assets not owned or controlled by the reporting organization but are part of the organizations value chain.
Companies can struggle with Scope 1 facilities emissions, especially when a vital technology has few mature replacement options. For example, thermal heating, manufacturing, and industrial processing are notoriously difficult to decarbonize. Traditional ICE vehicles also fall under the Scope 1 direct emission category, and EVs provide a viable alternative for industry fleets.
As the electric vehicle market rapidly transforms, companies can leverage battery-electric fleet vehicles to shift their difficult-to-decarbonize Scope 1 emissions to the Scope 2 bucket. Unlike Scope 1, there are numerous strategies for eliminating Scope 2 emissions in carbon footprints. Methods include green utility tariffs, procuring renewable energy via Virtual Power Purchase Agreements (VPPA), and installing Distributed Energy Resources (DER). Trends in the generation market also point to a lower carbon footprint of grid-delivered electricity.
Decarbonization Benefits of EV Adoption
Since 2005, nationwide carbon emissions from electricity consumption dropped by 33%, while total generation grew by 2%. This indicates each unit of electricity is cleaner by one-third than it was 15 years ago.1 This trend will only accelerate as renewable energy grows nationwide. Companies that adopt electric vehicles may see cost savings, while also having corresponding decarbonization benefits. Trends like this show how EVs provide value to a carbon inventory beyond the initial purchase.
In all U.S. domestic electricity markets, shifting from ICE to EV will reduce the overall GHG inventory in moving from Scope 1 to Scope 2. However, the realized GHG reduction created by electric vehicles depends on multiple factors. First is fuel consumption, heavier vehicle (e.g. freight trucks) typically have high carbon emissions due to their vehicle weight. Therefore, when heavier vehicles are replaced with an electric comparable, the higher the carbon savings.
Generation fuel mix, vehicle type, and time of charging can all impact the final Scope 2 metric. The carbon intensity of the grid can even vary widely depending on your location. The following diagram illustrates this difference by comparing Ohio, Massachusetts, and California using the EPAs eGRID Project data.

Develop a Fleet Electrification Roadmap with Edison Energy
The Transportation Electrification team at Edison Energy takes a flexible approach to helping client’s transition to EVs. By coordinating with organizations, utilities, and fleet managers, we can provide a comprehensive EV adoption strategy that maximizes both cost and carbon savings. For more information on how to decarbonize with EVs visit the second installment of our Transportation Electrification Series or contact us.
[1] U.S. Energy Information Administration (EIA) – Ap
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