Range-extended option for MX-30 EV includes the return of the rotary engine - but not necessarily how you'd think
The limited 124-mile range of the Mazda MX-30 electric crossover has been addressed in the eccentric kind of way that only Mazda knows how. The new Mazda MX-30 R-EV is a range-extended EV with a rotary petrol engine under the bonnet, which acts as an electricity generator only, it never drives the wheels directly. The pure EV remains on sale alongside it.With a 17.8kWh battery, which is half the size of that in the EV, the MX-30 R-EV has an electric-only range of 53 miles.Various driving modes can either deplete the battery to zero as an EV, run as a hybrid to a preset 45% of charge or maintain (or charge to) any battery increment from 20%-100%.Mazda is the only manufacturer to have made a long-term success (although it has generally been a niche one) of the rotary engine, in which a triangular-shaped rotor spins around a central output shaft within a fixed oval-shaped block, creating three combustion chambers as it spins. Each chamber completes one combustion cycle – intake, squeeze, bang, exhaust – per turn. So with one rotor, as here, which has a combined 830cc capacity between the three chambers, you in essence have a small-capacity three ‘cylinder’ (although they’re not cylindrical) engine. Because the movement is always rotational, there’s no reciprocating motion, so it’s very smooth.Previous Mazdas have had multiple rotors (the RX-8 had two, the Le Mans-winning 787B racer had four), each adding three chambers to the mix. Hence the four-rotor (so 12-chamber) 787B screamed like a V12 and then some at 8500rpm.Kota Matsue, the general manager of Mazda’s powertrain division, has had to explain to otherwise knowledgeable Mazda insiders – I gather to some disappointment – that this famous noise wouldn’t be accompanying a single-rotor generator that tends to run from 2300rpm to 4500rpm. But, he says, the advantages are that it’s lighter and more compact and smoother than an equivalent four-stroke engine; and that the output shaft is in the middle of the block, which is where you would want it to drive the generator to which it's bolted. Plus it’s nicely weird.Anyway, this rather complex ICE sits transversely beneath the bonnet, as does the electric drive motor, which powers the front wheels.The 50-litre fuel tank sits beneath the floor, along with the battery, which can take DC charge at a maximum of only around 36kW but, being little, gets filled up quite quickly.The rotary engine makes 74bhp, but that doesn’t matter, because it never drives the wheels directly. The electric motor makes 168bhp, but the battery output can’t quite keep up with that, so in hybrid mode under hard acceleration, the engine and generator pitch in to make up the difference (or even in EV mode, if you wilfully pass the throttle’s kickdown stop). As a result, the 0-62mph time is 9.1sec, rather than 9.7sec for the 143bhp MX-30 EV. If all this sounds complicated, don't worry: as a driver, you don’t need to know it. You just set the drive mode and away you go, as an EV if you like on the daily commute, with the backup range for visiting gran at weekends.Shift paddles change the retardation level and mostly it hums along electrically and smoothly with, under acceleration, the occasional distant mid-range whirr of a rotary being run at full load, sounding a bit like somebody running a masonry drill three doors down.Like the regular MX-30, it’s quite good fun to drive, with suspension that’s comfortable enough around town yet controlled enough to give it a bit of pep on the open road. The R-EV is 131kg heavier than the EV. And I like the interior. There’s a rotary controller for the top touchscreen and some quirky, quite cool material choices, like cork and a padded leather.The car has some character – like rear doors that you can open only after the front ones – to which the R-EV drivetrain only adds.On a drive like ours, of several short loops from various charge levels and while trying all the different modes, it’s hard to keep tabs on the exact efficiencies. But like most plug-in hybrids, it’s variously less efficient than either a pure EV or a pure ICE car: over 53 electric miles, I saw less than 3mpkWh; and when maintaining a constant battery level, I saw around 34mpg.Don’t buy this car if you want outright efficiency, then, but do consider it if it’s the convenience that matters more. Given the pure EV has a small battery, it’s (relatively) affordable, with prices from £31,250. The R-EV has the same trim levels and similar prices (slightly more expensive, top trim aside). However, with 21g/km of CO2 emissions at the exhaust, it incurs an 8% rather than a 2% benefit-in-kind tax rate.Mazda knows the MX-30 EV is a niche choice, given that it’s a 4.4-metre long crossover with suicide rear doors, small rear seats and a little battery. But it’s finding that for those who it does suit, it does so well. The R-EV version will broaden the range appeal – a little – while remaining endearingly odd.Â
