Electric drive systems produuce zero emissions at the point of operation, and therefore represent the cleanest and most environmentally attractive choice for larage trucks, as well as road vehicles in general. While electricity generation usually produces some emissions, it is easier to mitigate pollutants at a large power plant, so emissions per unit of energy generated and used are typically much lower than when fuel is converted to mechanical or electrical energy on a moving vehicle.

In 2007, the California Energy Commission commissioned a “Well to Wheels” study which estimated that heavy-duty trucks using a standard mix of electricity produce 27 g of carbon per MJ of energy used, versus 88 g/MJ for low-sulfur diesel trucks.1 Hence an electric truck can be expected to reduce carbon emissions per unit of energy consumed by about 69%. However, as electric trucks are also more energy-efficient than conventional diesel trucks, the total emissions benefit is actually enhanced. As indicated in the table below, an electric truck that consumes 3 kWh or electrical energy per mile will produce about 8.75 million grams of carbon emissions per year, versus more than 77 million grams of carbon for a diesel truck that gets 5 miles per gallon.

This is a benefit of nearly 90%, and will increase over time as more and more of our electrical power is generated from renewable, non-polluting sources such as wind and solar.

Carbon emissions for electric versus diesel trucks .

.

Electric trucks provide similar reductions in other pollutants such as oxides of nitrogen (NOx), carbon monoxide, and particulate matter.

1. Tiax, LLC, Full Fuel Cycle Assessment: Well-to-Wheels Energy Inputs, Emissions, and Water Impacts, Consultant Report prepared for California Energy Commission, 8/1/2007; CEC-600-2007-004-REV