MORE than any other manufacturer, BMW has a tricky balancing act to perform.

Performance and driving dynamics have long been BMW’s core values, but with ever-growing sales to a market not just aware of, but taxed on, environmental benchmarks, producing those Ultimate Driving Machines has never been trickier.

However, BMW is hoping to demonstrate with its new 1 Series that driving pleasure doesn’t necessarily mean poor environmental performance.

Introducing its new ‘Efficient Dynamics’, BMW is clearly intent on continuing to provide enjoyable drivers’ cars with a green twist.

BMW has used the launch of this new, sportier-looking three-door version to introduce a series of subtle exterior and interior changes to the entire 1 Series range, as well as a number of new technologies in powertrain and braking to limit emissions.

All new 1 Series models now benefit from Brake Energy Regeneration. Like a hybrid, this system scavenges electrical power from the brakes and engine on overrun, reducing the need for the engine to produce power for auxiliary controls, to the benefit of fuel economy.

An optimum shift guide has been incorporated too, with a light informing the driver when best to change gear. Those two things alone help economy markedly, allowing the range-topping 130i to improve its consumption to 34.0mpg, up from 30.7.

However, with just 431 of 2006’s 22,033 1 Series sales being the range-topping six-cylinder, that’s hardly going to make a huge impact. In the far bigger volume four-cylinder cars it will, though, with 40% of these being bought with company money. In addition to the regenerative brakes and optimum shift guide, the four-cylinder models, both petrol and diesel, benefit from an automatic stop/start function which stops the engine when neutral is engaged at traffic lights or in stationary traffic.

Adding that stop/start system in both diesel and petrol variants makes for an impressive reduction in consumption and emissions across the entire range. Helping here too is the petrol engines’ new high-precision injection, which allows a greater spread of the engine’s performance to operate in a lean-burn mode.

The benefits are obvious when looking at the combined consumption figures. The 118i and 120i, which like the diesels share a 2.0-litre engine in different states of tune, return 47.9mpg and 44.1mpg respectively on the official combined consumption cycle. That’s an improvement of 9.2mpg with the smaller engine, and 5.9mpg with the 120i.

BMW has achieved this without sacrificing performance. The 118i manages 0-62mph in 8.7 seconds, while the 120i covers the dash in a respectable 7.7 seconds. Emissions have dropped too, the 118i producing just 140g/km, the 120i 152g/km.

The diesel range shows similarly impressive reductions. The 118d now returns 60.1mpg on the combined cycle and emits 123g/km, the 120d managing 57.6mpg and 129g/km. That’s a marked improvement over the 150/152g/km of the diesels in the outgoing five-door.

Those efficiency and emissions improvements are repeated across the range and the only difference between the three and five-door models is an increase of 0.1 of a second on their 0-62mph times for the additional doors.

BMW anticipates the three-door taking around a quarter of 1 Series sales. The three-door arguably works better as a design and costs £530 less (£495 for M Sport models) too.

The 1 Series is regularly criticised for a lack of rear legroom and buyers are unlikely to be buying BMW’s entry car with practicality in mind, so it’s likely that many more will be attracted to the three-door’s smarter looks in this image-conscious market.

Behind the wheel

CHANGES to the interior of the 1 Series are as subtle as they are to the exterior. Look hard and you’ll notice better-quality plastics and on the three-door, there is a four-seat layout (a traditional rear bench is a no-cost option), but five people in a 1 Series was always ambitious anyway.

Spec your car with iDrive like our test car and you get an improved system, with favourite shortcut buttons helping its user-friendliness. A standard auxiliary socket allows you to plug in your MP3 player, but for full control an optional USB port is also offered.

With only the 120i to sample, the new 1 Series three-door felt much like the five-door models we’ve driven before. The interior feels lighter, though, the larger door openings and door glass area working better than the rather claustrophobic five-door.

As the only car in this class with rear-wheel-drive it remains an impressive driver’s car. The steering is light and precise, the chassis nicely balanced. Refinement and comfort is also impressive, and the roads on the Portuguese test route, with its smooth Tarmac, didn’t cause any problems for the suspension. Whether it’ll be quite as unflustered on our terrible surfaces is questionable.

This new car is all about economy, however, and the stop-start system does a remarkably good job. Pull up to a stop and select neutral and the engine stops. To restart, just dip the clutch. It’s a strange feeling at first and even trying to catch the system napping by dipping the clutch very quickly didn’t faze it – it always started immediately and pulled away smoothly.

Verdict

THE addition of a three-door model and new technology have made the 1-series an even more tempting fleet proposition. And the improvements in economy and emissions have been made without sacrificing its enormous driver appeal.

Model:		1.8		2.0		3.0		1.8d		2.0d
Max power (bhp/rpm):		143/6,000		170/6,700		265/6,650		143/4,000		177/4,000
Max torque (lb-ft/rpm):		140/4,500		155/4,250		232/2,750		221/2,000		258/2,000
Max speed (mph):		130		138		155 (limited)		130		142
0-62mph (secs):		8.7		7.7		6.0		8.9		7.5
Fuel consumption (mpg):		47.9		44.1		34.0		60.1		57.6
CO2 emissions (g/km):		140		152		197		123		129
On sale:		May
Prices (OTR):		£16,360-£28,390