But there are a few who would seem to disagree with your results.
Such as: the California Air Resources Board, Los Angeles Department of Water and Power, Argonne National Laboratory, and the National Renewable Energy Laboratory (DOE).
Just a couple of points. The Wiki article you reference uses 'BEV's with NiMH batteries' to get its figure of 0.2–0.3 kWh/km. The Tesla and most other current production EV's are using Li-ion batteries and improved battery charging/motor control circuitry. Tesla claims to require only 0.11 KWh/km, and I'm assuming any other vehicle using the AC Propulsion drive system (such as the TZero and Venturi Fétish) would get similar results. If that's accurate, it would about halve your CO2 output per mile number. While not all EV's on the road can claim that kind of efficiency, production vehicles will only tend towards greater efficiency overall in coming years. ICE vehicles, though progress has been made in recent years, can't begin to approach EV's in the "tank to wheel" department, and won't anytime soon.
Also, the comparison of emissions from ICE and EV's should cover a period of time or mileage that will be reflective of the vehicle's lifetime CO2 output, rather than its output when new.
The U.S. Environmental Protection Agency estimates that tailpipe emissions increase
25 percent for every 10,000 miles traveled. As gasoline cars age, their engines, catalytic
converters, and other emission control devices become less efficient. The cleanest a
gasoline car ever will be is the day it rolls off the assembly line.
The deterioration of emission control systems on ICE vehicles can increase emissions
up to 90 percent.
--- recharging the electric vehicles using coal-fired
power plants would result in carbon-dioxide emissions 17 to 22
percent less than those of the corresponding gasoline versions.
With today's national electrical power mix—which includes both
nuclear and hydro capacity—EV emissions would be 46 to 49 percent
less; if recharged by natural gas power plants—the likely
source in many locations—48 to 52 percent less; if recharged by nuclear,
hydro, or solar plants, carbon-dioxide emissions would fall
to virtually zero. As these simple estimates suggest, no matter
what the mix of generating plants, in city driving using battery powered
versions of these paired vehicles, EVs would bring carbon-
dioxide emissions down far below what they would be with
gasoline-powered vehicles.
Twenty million EVs, each with 100,000 miles on the odometer, would reduce CO2 emissions in this country by 500 million tons without building more power plants.
In a study conducted by the Los Angeles Department of Water and Power, EVs are
significantly cleaner over the course of 100,000 miles than ICE cars. The electricity
generation process produces less than 100 pounds of pollutants for EVs compared to 3000
pounds for ICE vehicles. See Table 3.
CO2 emissions are also significantly lower. Over the course of 100,000 miles, CO2
emissions from EVs are projected to be 10 tons versus 35 tons for ICE vehicles.
Many EV critics remain skeptical of such findings because California’s mix of power
plants is relatively clean compared to that in the rest of the country. However, in Arizona
where 67 percent of power plants are coal-fired, a study concluded that EVs would reduce
greenhouse gases such as CO2 by 71 percent.
Similar comparisons to those in California and Arizona can be found in the
Northeastern part of the country where the majority of power plants are coal-fired.
A study conducted by the Union of Concerned Scientists found that EVs in the
Northeast would reduce CO emissions by 99.8 percent, volatile organic compounds (VOC)
by 90 percent, NOx by 80 percent, and CO2 by as much as 60 percent.