Honda Insight five-door hybrid
Less pious than the Prius?
Urban economy is helped by a very efficient stop/start system, just keep your foot on the brake and the engine switches itself off. Take your foot off and the engine starts.
A true family-sized five-door, five-seater
The Insight's CO2 emissions are rated at 105g/km, which is enough to get you into the VED Band B £15-a-year car tax bracket but is a higher emissions figure than the 104g/km that Volvo claims to get from its new DRIVe 1.6 turbo diesel C30 and V40 models. Register Hardware has driven both those cars and managed to get a very similar fuel consumption figure to the Insight's. Frankly, both felt faster and where rather more fun to drive. Unlike Honda, Volvo thinks car buyers after an eco-ride will put up with visually challenging low-drag wheel trims.
Of course, when it comes to CO2 the Prius goes one better and only pumps out 89g/km. That means Band A and no car tax.
Whereas Toyota's Synergy Drive system allows the Prius to operate in a low-speed EV or electric-only mode with the petrol engine wholly out of the equation, that's not a trick the Insight's Integrated Motor Assist system can pull off. This is down to the Insight having a simpler - and thus cheaper - drive train than the Prius.
While the Insight is capable of running on battery power alone, the transmission is still turning the engine over as it does so. While this is happening, the Variable Cylinder Management (VCM) system closes the cylinders so no fuel is being burnt but in terms of engine noise you don't notice the difference between low-speed driving using the petrol engine and low-speed driving using the electric motor. The upside of this is that the transition between petrol, electric and hybrid drive is totally seamless. The downside is that the engine is still imposing drag on the system and so draining the battery faster than is strictly necessary.
According to Honda, battery-only drive only occurs when you're cruising at below 50kpm (31mph). During our test, we only managed to obtain reliable and long-term battery motoring while stuck in a slow-moving tailback on the M6 and travelling at around 15mph. A shade under two miles was the best be managed before traffic speed picked up and the engine kicked in.
There's a cubbyhole in the boot - but no spare wheel
On one rare occasion, we saw the dash indicate battery-only propulsion at a shade over 50mph, which shouldn't be possible. That may have had something to do with the fact that it was one of the odd instances on the open road when the battery was showing a 100 per cent charge, so presumably the system was looking for ways to use the charge effectively and not run the risk of having to 'waste' energy from the regenerative brake generators.
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