It's entirely obvious that internal-combustion cars pose a threat not only to the environment, but also to human health.
Exhaust from gasoline and diesel cars contributes to air pollution that can lead to deleterious health effects after long exposure.
Now a new study from the American Lung Association in California aims to quantify the health costs related to those exhaust emissions.
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It estimates that in 2015, the costs of internal-combustion cars on the health of residents in 10 selected states totaled $24 billion.
Researchers analyzed health costs in the 10 "Zero-Emission Vehicle states" that have adopted California's stricter emissions limits.
Besides California, these states are Connecticut, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Rhode Island, and Vermont.
2015 Nissan Leaf, Denver, Colorado, Mar 2016 [photo: owner Andrew Ganz]
The $24 billion in estimated 2015 health costs included the impact of 220,000 work-loss days, 109,000 exacerbated cases of asthma, "hundreds of thousands" of other respiratory health impacts, and 2,580 premature deaths, according to the study.
But researchers also concluded that those costs could be substantially reduced through mass adoption of electric cars.
Under the study's most optimistic scenario, zero-emission vehicles would make up 100 percent of new-car sales in the ZEV states by 2050, and would make up 65 percent of cars on the road in those states.
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If the states remain on track to reach that goal, electric cars could save $13 billion in health costs annually by 2030, and $21 billion a year by 2050.
The analysis predicts 1,429 fewer premature deaths from air pollution in 2030, and 2,246 in 2050 in the 10 states.
The report included estimations of "upstream" emissions related to generating the electricity needed to power electric cars.
2016 Nissan Leaf
The model assumed a fossil-fuel heavy mix, with a single generic grid profile applied to all states.
Limited resources prevented making calculations based on states' individual grid profiles, William Barrett told Green Car Reports.
He's the policy manager of the American Lung Association in California.
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The U.S. grid is slowly decarbonizing, with coal being replaced by natural gas and increasing amounts of renewable energy entering the mix, though the effects vary widely among states.
Under another scenario with greater reliance on renewable energy, Barrett said, health benefits increased by more than 40 percent.
In addition to the health benefits, the study found that mass electric-car adoption could result in additional savings from avoiding climate change.
Climate-related benefits could equate to $5.5 billion in annual savings in 2030, and $12.8 billion in 2050, the study found.
The 10 ZEV states studied have already pledged to put 3.3 million zero-emission vehicles on the roads in their jurisdictions by 2025.
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However, only California currently has a zero-emission vehicle mandate that requires automakers to sell those cars within its borders.
California also leads the other states in electric-car incentives, as well as policies that encourage the construction of charging infrastructure and use of renewable energy.