Even as installations of fast and public chargers for electric cars have taken off, they have not kept pace with the number of new electric cars automakers have sold.

Now states and utilities are trying to get ahead of a potential similar problem for trucks.

Following on an earlier model for the West Coast Electric Highway, a network of electric-car chargers primarily on the I-5 corridora study released last Friday looked at how best to support a coming wave of electric semis and other commercial trucks delivering freight up and down the corridor. 

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Tesla has been testing two Semis around the West Coast (primarily in California, Nevada, and Arizona), and plugging into multiple Superchargers at a time to charge. Clearly, blocking several chargers with big trucks won't work, once they start becoming common on the road.

The study organizers also recognize that the most convenient places to stop for cars aren't necessarily the same places that truckers might need to stop, with more blacktop, and more facilities to stay longer to fulfill their federal rest requirements.

The states of Washington, Oregon, and California are joining forces in the study project, called the West Coast Clean Transit Corridor Initiative, and will be joined by Southern California Edison, Portland General Electric, Pacific Power, Seattle City Light, the Sacramento Municipal Utility District, and Edison International.

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They will focus on the Interstate 5 corridor along with connecting routes. The agencies say that freight traffic is a major source of air pollution in the region, and converting some of that traffic to cleaner electric vehicles could take a big bite out of smog.

Pacific Power spokesman Scott Bolton said in a statement, "Well-planned electric charging infrastructure along I-5 is important to our region. The I-5 corridor is the economic backbone for transporting essential goods and services to our Oregon, Washington and California customers. We see investments in transportation electrification and electric charging infrastructure as a great way to support the economic vitality and environmental quality of communities along the corridor."