A gap is growing between areas of the country that are switching from gas-powered to electric vehicles at a steady clip compared to those that aren’t as EV sales have now reached 8.6% of new-vehicle retail sales.

A J.D. Power study found that year-over-year, EV adoption had a modest one index point national bump in the first half of the year to 21 on a 100-point scale. The 10 states with the greatest EV adoption also increased, but the 10 states with the slowest adoption rates fell.

Adoption rates will continue to be uneven through at least 2035, J.D. Power forecasts. It predicts that California will achieve an astounding 94% EV share by then, automaking center Michigan just 41%, and North Dakota still under 20%.

Affordability, which has consistently been a major obstacle to EV adoption, will prove volatile over the forecast period. J.D. Power said that affordability improved 15 index points in the first half of the year but was skewed by a series of Tesla price cuts. It said that as other automakers debut more  EVs, affordability levels will fluctuate.

States that have been quick to offer EV purchase incentives and to build up charging infrastructure have had the greatest adoption rates, J.D. Power says. They are California, Washington, Hawaii, Oregon, Nevada, Maryland, Arizona, Colorado, Utah and Massachusetts. Those with the lowest adoption rates are Michigan, Iowa, Kansas, Arkansas, Mississippi, Wyoming, Louisiana, the Dakotas and West Virginia, their rates falling on average in the first half of 2023.

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