No one sells more diesel cars than BMW in Singapore. After spending three weeks experiencing BMW TwinPower Turbo technology, it’s not hard to see why

SINGAPORE — My favourite story about diesel power is how Rudolf Diesel was thrown off a ferry one dark, mysterious night. Probably by agents from Big Oil, because he’d invented an engine capable of running on peanut oil, after all.

Well, no one knows that for sure, but it makes for a good story when someone asks why you bought a diesel car: “Because the technology is so efficient, Big Oil tried to keep it down, man!”

Poor Rudolf’s body did turn up eventually, in case you were wondering. It was in such a state that they searched his pockets and then returned it to the sea.

After a story like that, you deserve a kitten…

If only he could have lived to see his engine elevated to the state it is in today, particularly in the form of a modern BMW TwinPower Turbo engine.

That’s been my main thought after three weeks with the BMW 116d, one of the cars behind BMW’s huge success in selling diesels in Singapore.

Figures from the Land Transport Authority show that 1,769 BMWs registered in Singapore in 2016 were powered by BMW TwinPower Turbo diesel engines. No other brand came remotely close to that level of sales success with diesel power.

Many of those were accounted for by the BMW 116d. My first impressions when collecting the car? It’s deceptive.

There is supposed to be only a 1.5-litre, three-cylinder engine under the BMW 116d’s bonnet, but drive it and you would be tempted to peek, just to make sure they didn’t sneak something bigger in.

READ MORE > Here’s our review of the BMW 116d

It’s seriously peppy for something so small, and the BMW can gallop to highway speeds so breezily that it’s bound to make you smile. But the other way in which the car deceives is that no one can tell it’s a diesel. A common complaint about diesel engines is that they sound gruff, but I literally encountered not a single comment along those lines about the BMW TwinPower Turbo engine.

One of the rules of the office is that whoever has a test car in the parking garage is obliged to drive everyone out to lunch. After days of this happening, no one remarked on the fact that the BMW 116d was diesel driven.

No one commented on the BMW 116d’s engine note, but the smell of our man’s biking gear was a different matter altogether…

Mind you, this isn’t true of all diesels. Some diesel engines do sound like someone at the factory forgot to tighten half the bolts, but not the BMW TwinPower Turbo. A cultured murmur is what you get from the engine compartment, rising to the occasional purr under hard acceleration.

Perhaps sound insulation in all the right places plays a part, but the typical smoothness of a BMW engine and the finely-controlled, highly-precise fuel delivery system of the engine must be responsible, too.

Whatever the reason, refinement and diesel propulsion are no longer mutually exclusive.

When is 18.9km/L a poor score? When you’re in a BMW 116d. We did improve, though, thanks to the Eco Pro driving mode

But now comes the best part: how little it costs to feed a diesel.

Diesel engines are generally more efficient than petrol engines for a number of reasons, but the main thing is simply that the fuel is more energy dense. A litre of diesel contains more calories than the same volume of petrol, in other words.

In fact, in other industries fuel is sold by the weight but we buy it by the litre, and a litre of diesel weighs around 100g more than a litre of petrol. So not only does diesel cost less per litre, but you actually get more fuel per litre at the pumps.

This is why diesel drivers always look so jolly at the filling station

Monitoring your fuel use in the BMW 116d is easy enough along the way. Bright displays about your fuel consumption history put it into an easy-to-red bar graph, allowing you to track your efficiency — and whether someone’s been naughty after you loan them the keys.

Engaging the EcoPro mode using BMW’s Driving Experience Control selector makes it even easier to conserve fuel. It automatically puts the engine and eight-speed transmission into a fuel-sipping mode, reduces the air-conditioner output (which you can override on hot days), and even flashes handy fuel-saving driving tips on the display, to help you improve.

Making liberal use of Eco Pro mode, we ultimately covered 1,518km in the BMW 116d over close to three weeks, with two stops for diesel: one for 23.8L (which cost $30), and a final top-up of 52L for $65.52.

Jasmine from Performance Motors fills up the tank, and kindly picks up the tab. Diesel may be cheap, but we’re even cheaper

That means the BMW returned a smidgen over 20km/L, in real-world driving conditions. That’s a little less than the 24.39km/L that the car can average in laboratory testing, but given the constant temptation to enjoy the engine’s torque, it’s perhaps understandable.

But even at our rate of fuel burn, based on the average mileage in Singapore, a BMW 116d would need 874L of diesel a year, at a cost of around $1,100.

Rudolf Diesel’s engine no longer runs on peanut oil, of course, but it turns out that it costs peanuts to run a BMW 116d.