40 miles on battery alone. A three cylinder 1 litre engine driving the generator. Unless we're talking motorcyle engines that sort of engine would be shoving out about 50bhp. Not a lot to move a hefty great lump like that around. So it would be relying on it's batteries an awful lot. What's going to be charging the batteries when it's not plugged in? Presumably the excess power from the engine and regenerative braking. Long journeys do not in general see much braking and at motoway speeds you'll probably have little excess power from the engine to charge the batteries and need the batteries everytime you meet an uphill section.
It's not really suited to motorway or any other journeys over a handful of miles is it? Will it really produce less emissions than a carefully designed IC car? Before answering that bear in mind that the conventional car will weigh considerably less and won't have the overhead of driving a generator to power electic motors. So the IC powered car will probably give better fuel mileage anyway. On short journeys where you can recharge between trips, but on longer journeys I suspect an IC powered car designed with economy in mind will produce less CO2.
That's the problem with so many of these EV projects. They seem to be very narrowly focused on city driving. Most of the manufacturers will admit that their cars are not suited to long journeys. What we want is an EV that will replace our current cars. What most EV makers seem to be offering us is a vehicle to use alongside our current cars. What a great idea, lets all buy an EV that costs more than our existing car and keep our existing car to use for longer journeys. Where are we going to get the money to pay for that, and the additional insurance and tax? Where are we going to keep all these cars? An what will be the environmental impact of manufacturing twice as many cars?
There's a lot of nonsense around about the majority of car journeys being short hops, and that may be the case for those who live in big cities but the rest of us use our cars differently. My commute is 22 miles each way mostly on motorways, business mileage takes my daily total way above that of the commute and hardly a weekend goes by that I don't put in a journey of 150 miles or more. I'm far from alone in this sort of car use.
The solution to city transport is not an EV designed specifically for the job it's either a vehicle that can fulfil all our transport requirements, or a vehicle for extra-urban journeys and an urban public transport system that works. Can't see the latter happening while we have a government that sees public transport as a revenue stream rather than a public service which should be subsidised.