Extended-range EVs vs plug-in hybrids

In this piece, I mentioned that T&E research shows that plug-in hybrids produce almost as much CO2 emissions as petrol/diesel cars.

The Driven has also covered this report, but it added some detail about EREVs (extended-range electric vehicles) 

Extended-range electric vehicles (EREVs), like PHEVs, also rely on a combustion engine for their extended range, though they use a series configuration, which means that the combustion engine only ever recharges the battery and never provides power to the wheels directly.

According to T&E, EREVs usually have larger batteries than PHEVs and can therefore provide a longer electric-only range. This means that the combustion engine used for generating electricity is smaller than that found in a PHEV, since it does not need to provide power to the wheels.

However, even though EREVs can drive up to 900 kilometres, they are nevertheless still consuming 6.7 [6.4] litres of fuel per 100 kilometres when in combustion mode – similar to some European petrol SUVs.

One would expect a car running on a petrol engine to use almost as much fuel whether it's charging a battery or driving the wheels directly, so the fact that in combustion mode EREVs are still consuming 6.4 litres per 100 kilometres (45 mpg in the UK) isn't surprising, nor is it an argument against EREVs.  The critical number is how often the petrol engine has to run, in proportion to all the kilometres driven.  An ICEV would use petrol for every kilometre, plug-in hybrids, it turns out, use petrol most of the time, but EREVs only use petrol 30% of the time.

The chart below shows T&E's analysis.

With battery costs plunging, EREVs will be a short-term (5 year?) solution to low EV range and too few chargers.   If you live outside a major city in a big country (USA, Australia, Canada, Brazil, Argentina, India, South Africa, for example), EV range, except on the most expensive cars, just isn't enough for longer journeys.  In Europe, with its huge network of chargers, EREVs are prolly a distraction, as T&E maintain.  Elsewhere, while PHEVs are not a solution, EREVs are.