WITH ONE MAJOR styling update since its debut in 2005, the current generation E90 BMW 3 Series is due for retirement in the next couple of years.

Despite wearing some of the heaviest camouflage that we’ve seen on a BMW, new spy photos obtained this week show that development of the next generation 3 Series is well underway.

BMW’s EfficientDynamics technologies is expected to be a major element in the new 3 Series, with low-drag aerodynamics and smaller-capacity engines playing a role.

One of the new EfficientDynamics features will be an aerodynamic ‘air curtain’. A series of ducts and vents around the bodywork designed to irect air more cleanly around high-drag areas, such as the wheel-wells.

Ever-tightening emissions and fuel consumption regulations are expected to see the new 3 Series debut with a three-cylinder turbocharged engine, developing an estimated 110 to 125 kW and 200 to 300 Nm.

One rumoured addition to the engine range is a less-complex version of the hybrid drive system set to debut in the 7 Series and X6.

While BMW already has a range of fuel-efficient diesel engines on offer, the hybrid option is expected to be aimed primarily at the US market, where diesel take-up rates are lower than in Europe.

Thanks to the heavy camouflage, styling remains unclear for now. BMW has hinted in the past that the next 3 Series would draw inspiration from the Concept CS - elements of which can already be seen in the new 5 Series GT.

Our rendering, below, offers one idea of how the next 3 Series might appear.

The bonnet and belt-line are expected to sit higher than on the current model, offering improved pedestrian protection, as this rendering of the 2012 3 Series Touring demonstrates.