Review of the biofuelled Saab flex fuel 9-5

Bioethanol… it’s cheaper than petrol at the pumps, produces more power, uses of spare arable capacity to grow the raw materials, and it’s greener. Better yet, it’s here today.

Err… so where’s the catch? Well, for starters you’ll need a flex-fuel vehicle – one which can burn petrol, bioethanol or any mix of the two, as you please. At present only Ford and Saab market such an animal, though Renault and Volvo are poised. Then you’ll have to find some of the green stuff to put in it, which for most people isn’t easy at the moment.

And we’d better talk economics. At the time of writing, you’ll pay around £3.16 more for every 100 miles travelled in the Saab 9-5 investigated here, while the biofuel option adds £600 to its new price. Mind you, once on the move you’ll add around 70% less fossil-derived CO2 to the air. For more on costs, see Incentive needed, next page.

What about the car? Saab fields trade-name Biopower models across its range. Here’s a quick look at the 9-5 estate in Vector Sport trim, ranked one model below the top-line Aero and costing £27,695 on the road (£32,140 as driven).


Bioethanol’s power boost potential is a big draw. On cooking-grade unleaded, Saab’s 2.3 litre turbo four makes a workmanlike 185hp and 207lbf ft torque. Feed it pure E85 and outputs jump to 210hp and 229lbf ft, which shows up as a sharpening of response from the 9-5’s already broad-chested engine. Either way performance is strong and confident – on the quiet, this particular 9-5 is a bit of a hooligan.

Burning unleaded it hits 60mph in 7.5sec. On bioethanol it should be quicker but wasn’t – the same sprint took 8.5sec. It’s down to grip, as biofuel’s extra power forced the standard traction control to curb output more, and for longer, in the first two gears. On either fuel, torque steer – the tendency to dart off-line under hard acceleration – can be a pain, though that’s par for front-wheel drive cars.


Bioethanol is fermented from crops like cereals, sugar beet and sugar cane, or from woody materials. It’s fairly environmentally friendly, as combustion just recycles the atmospheric carbon locked up in the stuff it came from.

Engines prefer a sniff of petrol for easy cold starting, so in Europe the pure product is blended with 15% fossil fuel and tagged E85. Even so vehicle mods are needed, typically tougher valves/valve seats, higher capacity injection, and a compatible pump/materials for the fuel system.

UK bioethanol’s 107 RON octane rating is much higher than unleaded’s typical 95 RON, so it can stand higher combustion pressures without detonating. A modern turbocharged engine’s electronic controls exploit this, hiking boost pressure through wastegate control and bumping ignition advance until the engine’s knock sensor tells it to back off. The result is more power and torque.

But a gallon of bioethanol has only about 70% of the energy in a gallon of unleaded. So you need to burn about 30% more bioethanol to produce the same power, and thus fuel consumption worsens by the same percentage – in this test, mpg dropped by 28%.

E85 production is slowly ramping up in the UK. Last year the Morrisons supermarket chain took the laudable step of installing bioethanol pumps on all its new forecourts, and at present those are the only outlets. Expect better coverage as more flex-fuel cars are offered.

Comfort, handing

Standard climate and cruise controls, multiple airbags, xenon headlamps and heated part-leather seats keep things civilised in a well-made, old-fashioned and not overtly luxurious cabin. Deep, soft front seats deliver good comfort, though tailoring a relaxed driving position takes work and may be hard for tall persons, as the seat’s offset means the centre console tends to rub you up the wrong way.

Two back-seat passengers get generous legroom and heated seats, while a luckless third gets a hard perch and the centre floor tunnel. Load space measures a good 1.1m x 1.0m at minimum with the rear seats up these split-fold simply to drop almost flat, extending floor length to 1.74m. That’s as long as Volvo’s big V70 estate, if narrower.

Noise is generally low, though rumble from sporty 45-section tyres should be less. The chassis’ handling bias produces a firm ride which complements the 9-5’s strong powerplant, teaming with light, direct steering to make this weighty estate quite nimble, if not in the Audi league.

Through bends the 9-5 sits pretty flat and grips hard, rewarding gentle inputs more than rough treatment. The driveline isn’t so good – a ponderous five-speed manual shift and long-throw clutch make the £1300 auto option look attractive.


The cynics are right: There is no free lunch, though it does depend on how you define free. Right now, travel by Saab Biopower estate costs you more and the planet less. But if you’d like to go green, this cheery Swede will give you some fun on the way.


Here’s a rough guide to how running costs stack up. At the time of writing, E85 cost 81.9p/litre against unleaded’s 85.9p/litre, saving 4p/litre. That’s good. But in line with expectation, the Saab’s mpg dropped from 27.6mpg (unleaded) to 21.5mpg (E85).

Combine the two factors, and you’ll see that a 100-mile trip on bioethanol will set you back an extra £3.16 (22%). So for now at least, your pocket loses.

Things should change. The Chancellor big-heartedly knocks 20p/litre off E85, the same reduction given to biodiesel. But the fuel makers reckon that low demand means high production cost, so by the time E85 arrives at the pumps it’s only 4p/litre cheaper than unleaded.

More flex-fuel cars on the roads will mean better demand and if the Chancellor helps things along with bigger tax breaks on vehicles and fuel, the economics of running on bioethanol will look rosier.

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