Last September, the Vermont Legislature passed the Global Warming Solutions Act. Among other things, the act requires Vermont to reduce its greenhouse gas emissions by specified increments over the coming years: 26% below 2005 levels by 2025, 40% below 1990 levels by 2030, and 80% below 1990 levels by 2050. In recent weeks, several state agencies and advocacy groups have released reports showing where Vermont stands now in terms of meeting these requirements, and what remains to be done.

Carbon emissions in Vermont have declined slightly in recent years, from 9.54 million tons of carbon dioxide equivalent in 2015 to 8.59 million tons in 2019. The decline is largely due to changes in the mix of sources from which the state’s electric utilities obtain power. Green Mountain Power, Vermont’s largest utility, now purchases most of its power from Hydro-Quebec.

While only 6% of Vermont’s emissions now come from electric generation, some environmentalists believe that GMP’s heavy reliance on power from enormous hydro projects in northern Quebec is not consistent with the state’s goals that emphasize smaller-scale renewable electric generation. Hydro-Quebec’s dams have been associated with damage to northern Canadian ecosystems and significant carbon releases from trees submerged by the damming.

To meet the 2025 and 2030 mandates in the Global Warming Solutions Act, Vermont will need to reduce its greenhouse gas emissions by 14% between now and 2025, and by a further 30% between 2025 and 2030. The conclusion of every analysis of these requirements is that most of the emissions reductions will have to come from the transportation and heating sectors, which together account for about 70% of Vermont’s production of greenhouse gases.

There are currently between 4,000 and 5,000 electric vehicles registered in Vermont, divided roughly equally between plug-in hybrid models and all-electric models. The number of electric vehicles has been increasing by about 20% each year, and they now make up about 7% of all new vehicles registered in the state. In order to meet the 2025 emissions requirements, analysts estimate that the number of electric vehicles in the state would have to grow ten-fold over the next four years, to between 45,000 and 50,000 vehicles in 2025.

State and federal incentives are available for the purchasers of electric vehicles, and some policymakers have advocated for a new version of the 2009 “Cash for Clunkers” program that would provide grants to motorists trading a gasoline- or diesel-powered vehicle for an electric or hybrid one.

One obstacle to increased electric vehicle use is the lack of available charging stations. The combination of Vermont’s low population density and concentration of jobs in a relatively small number of regional centers means that Vermonters have longer commutes, on average, than the residents of any other New England state. With few charging stations available, Vermonters who must drive a fair distance to work have been reluctant to purchase electric vehicles.

The recently passed state budget includes provisions that will use federal funds from the American Rescue Plan to build out a robust network of charging stations around Vermont in the next several years. The new charging infrastructure would be located along highway corridors, in downtowns and village centers, at other employment centers such as hospitals and college campuses, and at multi-family housing developments.

Other measures needed to reduce emissions from transportation include reducing the number of single-occupant vehicle trips by providing incentives for ridesharing, extending public transportation routes and frequency of service, and encouraging employers, where appropriate, to continue to allow work-from-home in order to reduce the number of miles driven by commuters.

Vermont’s transportation emission target for 2025 will not be met unless the percentage of electric vehicles increases from the current 7% of new registrations to about 25% over the next four years. This will require a robust combination of purchase incentives and investments in charging infrastructure.

Eric L. Davis is professor emeritus of political science at Middlebury College.