Road Test: BMW 520d EfficientDynamics

Price as tested: €43,985

+ Startling economy, refinement, comfort, deportment
– Occasionally jiggly ride, feels a bit too big
= Astonishingly, one of the most economical all-round cars we have ever tested

I know I should be getting used to it by now. I know that BMW has been pulling economical and emissions rabbits out of hats since its Efficient Dynamics programme was introduced back in 2007. But the overall economy of this 520d ED simply startled me. It is staggering to think that this large, comfortable, luxurious saloon should be able to average better than 50mpg. But it can. Far better under certain circumstances.

We’re used, on these pages, to pillorying car makers for not being able to produce vehicles that an reproduce their claimed fuel consumption figures in the real world. The fact that cars can achieve such figures, under rigorous laboratory conditions is admirable. And it is only because the EU tests cars under those stringent laboratory conditions that we can make a properly scientific comparison between the performance of different cars. The figures are all recorded under identical conditions, so they are comparable. By contrast, comparing the figures we achieve under normal user conditions is the scientific equivalent of sticking a finger in the air to gauge wind speed. Yes, the cars we test on these pages are driven, generally, over the same network of road, but the conditions for each test can be wildly different. Wind, ambient temperature, traffic and a thousand other factors all come into play, so take both official and observed figures with a pinch of salt.

However, and having said all that, the 520d ED is only the second car (the first was a VW Golf BlueMotion) that actually matched its claimed economy figure. Not over my whole week with the car (that figure worked out at 5.4-litres per 100km, or 52mpg) but on one long journey, between Schull in West Cork and Cork city, the 520d averaged exactly 4.5-litres per 100km, or 62.7mpg. Precisely the figure that BMW quotes for it.

That was not achieved after stripping the car of excess weight and driving like a nun on her way to confession. The car was full of both people and luggage, and while I was observing the posted speed limit, neither was I exactly hanging around.

This, I remind you, is in a large, executive saloon with comfortable space for four adults, leather, aircon, sundry electronic gadgets and an all-up weight of 1,695kg. It has 184bhp for heaven’s sake, and sprints from 0-100kmh in a GTI-like 8.1secs. Yet its Co2 emissions rating is just 119g/km, thwarting the Government’s plan to punitively tax such tax-band-busting executive cars. Quite why Phil Hogan and Michael Noonan want to tax people out of such astonishingly efficient vehicles at a time when it costs more than €100 to brim their fuel tanks is possibly one for the conspiracy theorists...

As for the rest of the car, it’s standard 5 Series fare; subtly handsome body, deftly balanced chassis, ideally weighted (if less than perfectly communicative steering) and a handsome, beautifully made cabin. Its only flaw is its size, which seemed unremarkable when first we drove the current 5, but since testing the brilliant new 3 Series, it seems suddenly too broad, too big for Irish roads. Odd that, but it just goes to prove that the 3, as it always has been, is the natural gravitational centre of the BMW range.

But when you see a 520d ED pass by, don’t be tempted down the Government’s daisy path of assuming the owner to be a jammy bastard who should be compelled to pay through the nose for his or her road tax. Instead, appreciate the simple, yet effective engineering (weight reduction, active electronics to control the radiator grille, the brake energy recovery, the stop-start etc) that has gone in to trimming its consumption and emissions, and be thankful that such technology, so much more useful in daily driving than expensive, heavy hybrid tech, is already trickling through to more mundane, more affordable cars.

Despite its plutocratic nature, the 520d has already started a revolution against the rising cost of fuel. Arise, brothers and sisters...

Facts & Figures

BMW 520d EfficientDynamics
Price as tested: €43,985
Range price: €43,530 to €134,430
Capacity: 1,995cc
Power: 184bhp
Torque: 380Nm
Top speed: 226kmh
0-100kmh: 8.1sec
Economy: 4.5-100km (62.7mpg)
CO2 emissions: 119g/km
Tax Band: A. €160 road tax
Euro NCAP rating: 5-stars; 95% adult, 83% child, 78% pedestrian, 100% safety assist