Currently all American taxpayers are being taxed to subsidize electric vehicles.
I know what you are trying to say, but as worded, the statement above is misleading.
w.r.t. energy cost that goes into propelling EVs, those are fully taxed at the marginal electricity generation and distribution tax rates. Those vary by location, same as gasoline prices.
w.r.t. funding the road construction costs, the answer varies by municipality, and the type of a road (private tollway, public tollway, public free-to-use road) we want to discuss.
Then there is the whole matter of including (or not) the cost of externalities into the current funding models (air pollution at the pipe, at the point of fuel refinement, etc.), and the redirection of funds for obscenely wasteful social welfare projects ("biodiesel" funding for corn growers and refiners, etc.).
More interestingly, the funding for road construction in the US (and elsewhere) is extremely complex, and funding models vary by country.
More here: "“National Funding of Road Infrastructure: Summary"
http://www.governor.ct.gov/malloy/l...TDOT_Transportation_Funding_International.pdf
Otherwise I could see utility companies being required to meter the automobile charging circuit and collect a vehicle charging tax.
That would only be true if we all wanted to preserve the status quo of over-complex and over-pilfered US road construction funding model, where a part of the funding comes from fuel-surcharges. BTW, my own statement here is an over-simplification, since only a part of fuel surcharge goes to road construction and maintenance, and bulk of road construction is currently funded from other sources.
State (the largest) portion of gasoline taxes collected usually goes into "general fund", with the obvious implications of what happens next. About 60% of the Federal Highway Trust (HFT) funds go to road CapEx, the rest are diverted elsewhere:
https://en.wikipedia.org/wiki/Fuel_taxes_in_the_United_States
There is really no need to stick with the current over-convoluted US roadway construction and maintenance funding models.
My bet is that we will either abandon attempts to retrofit EV road-use taxation to the dyno-juice surcharging models, and adopt something else instead (less likely). Or add another layer of complexity by adding a new overlay taxation model (more likely).
There are too many fingers in the current pie to reform it clearly, so adding a new tax stream that can be pilfered is more probable
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