We drove the BMW i3 Rex: all the cleverness of “zen” e-power…


Living your everyday (urban) life on electric power now seems the way to go. Our governments want it, and will effectively promote it when they have the money to do so. Urban citizens in Europe and all over the world are convinced that ecological e-power will be the mobile lifeblood of our future cities. Indeed, not only the kind of energy, also the mobility concepts themselves are dramatically changing, and will be ever more individual and tailor-made through car renting and sharing. Clever, well made state-of-the-art compact electric vehicles, also with a distinct premium character, are needed for the modern (urban) public, and BMW is building it with this 3i. We drove it extensively for a week, and here are our findings…

Hans Knol ten Bensel

The 3i has a decidedly futuristic look, and certainly breaks aesthetic barriers with its individual proportions. We like the big wheels, the narrow, tall silhouette, the stylish front and end treatment. The rear doors with their idiosyncratic front opening and the fluently styled waistline is also pleasing to the eye.


The same can be said for the interior: it is even more innovating, with clean, downright postmodern, fluent lines. We like also the contrast between the rectangular instrument and navigation displays and the curved, flat and soft surfaces of the dashboard.


The 3i has cleverly placed controls, and although everything is rather special to manipulate, one finds quickly its way around and feels soon quite at home in this i3.



Under the skin, high-tech abounds, with a carbon bodywork, dubbed “Life Module” , resting on a “Drive Module” made of aluminum, containing electric and two cylinder petrol engine, and gears. The engines resorted to carbon to compensate for the weight of the battery pack.

 The “zen” of going electric

Electrical cars are very docile and quiet, fit for a “zen” approach to mobility. Indeed, driving from A to B is a quieting and downright restful experience in these “e” vehicles, and one arrives maybe a few minutes later at its destination, but always very relaxed.


The i3 will even reward you even with quite some driving pleasure, as the electrical engine develops not less than 125 kW, which guarantees more than brisk accelerations, at any speed, in all driving circumstances, as electrical engines develop a truly massive torque.. 0 to 100 km is absolved in 7,9 seconds, with especially accelerations in lower speeds up to 80 km/h being of very high caliber. Top speed is limited to 150 km/h. Fuel consumption using the range extender is quite low. Filling up the 9 liter tank with a mere 5 litres got us a range again of well over 180 km on petrol power alone, so quite frugal it is.


This allows rather spirited urban driving, as lifting the throttle unleashes quite good braking power, with the engine motor now acting as an efficient and rather powerful generator. Soon one learns to drive this BMW with good anticipation only on the throttle through traffic,  hardly using the brakes at all, if only for emergency stops.


On the open road, one rediscovers the forgotten virtues of rather sedate, anticipative “zen” driving, as the limited action radius of the 3i invites you to take things rather easy. Indeed, the battery indicator shows you precisely the remaining range in km, and as soon as this drops below 100 km, we felt the urge to be conserve the precious battery energy as much as possible.

So intuitively we cruised along at 80 or 90 km/h on the open road and motorways, allowing the eye to take restful glances at the surrounding countryside. Under these circumstances, the useable range of this i3 grew encouragingly.  A quiet 100 km drive from Antwerp to Knokke on battery power left us at arrival with 30 km to spare, and we did not have to use the range extender here at all. We drove the i3 here in the “comfort”  mode, but we carefully avoided strong accelerations and cruising speeds above 90 kmh.

We noticed that the range indicator of the range extender also took account of the driving style we had adopted, as the indicated useful range here had grown to 156 km.


Indeed, our i3 was equipped with a range extender, and we used it on the return drive of our coastside weekend. Normally, this range extender sets in automatically when in “comfort” mode, whenever battery power falls below 10 pct. There is a small arrow on the battery charge level indicator in the display which indicates the point where the range extender starts up. As soon as battery power drops below 75 %, one can also engage the extender manually via the iDrive knob.


This range extender actually consists of a 2 cylinder 38 HP petrol engine, which drives a generator. The electrical energy generated by this unit serves mainly to keep the charge level of the battery at a chosen rate. There is no direct connection between the combustion engine and the driven wheels. As said, the range extender can be used to maintain the battery charge at a given level, and when one anticipates that one cannot charge the battery for the expected return trip, it is wiser to use the range extender as a precaution to prevent emptying the battery.


Given the present density and availability of charging points in our country, this range extender is quite useful, and quite frankly, we would not buy an i3 without it.


We just mention here that one can also choose the Eco Pro and the Eco Pro + mode. Using these modes, the electric motor is then set for gradual accelerations, and comfort functions like airco, seat heating, etc. are reduced in power. The speed can also be limited between 80 and 130 kmh. In the Eco Pro+ function, the air co is completely shut off, and speed is limited to 90 km/h. It gets you further, but then in rather Spartan fashion!

Responsive chassis

We found the suspension and chassis ideally suited to the whole character of the car, coping very well with the impressive pulling power of the electric engine, and holding very well its own in terms of handling and agility. Indeed, the i3 corners with precision up to quite high speeds, and the narrow, tall 19 inch tires provide surprising lateral grip and stopping power. Braking is very good, and, as said, in everyday driving they are hardly used, as the e-engine provides marked deceleration as it turns in generator mode when not under power.


The i3 is quite practical with lots of cabin storage space in the centre console and door bins, and more than adequate boot space.

The 3i scores well in infotainment too, as it should considering the character of the car and its vocation as a premium level compact EV.

Charging your i3…

Getting the battery up to full power again proved rather easy. This BMW comes with an AC quick charger, and has also a “normal” electricity cord/charger. We used the latter in our private home and in Knokke in the apartment garage, and charging times varied between 5 and 14 hours for a full charge, depending on the distance driven on battery power, respectively 60 and 100 km.


One can choose charging times, for instance to take advantage of low tariff power, and set the car up for the chosen departure time, like warming up/defrosting the car before startup, for example…

When one has purchased an i3, one is well advised to install a home charging station, which considerably reduces charging times, and allows to complete a full recharge easily within the low tariff periods overnight.


The i3 is well built, surprisingly practical with brilliant “city” performance, where its acceleration power truly excels.


We also liked the good all round visibility and compactness of the car. City roads are its true element, whilst it has also very good performance in store on the open road, with handling and comfort to match. The rather limited action radius on e-power does not inspire however to use this available agility to the full. With the range extender, this is altogether another story. We found it very useful indeed, and given the present charging infrastructure in our country, one would be very well advised to purchase the i3 with this Range Extender.

It transforms the i3 into a very practical and useable “green” car, setting the score for the competition to follow…

Hans Knol ten Bensel



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