The South Korean brand will show off the i30 blue and i10 blue concepts at the Melbourne Motor Show.

There?s a distinct environmental theme at Hyundai this year.

The South Korean brand will show off the i30 blue and i10 blue concepts.

Both cars may look the same as a normal model but they deliver significant fuel economy savings and substantially reduced C02 emissions.

The i-blue package comprises advances in drag reduction, an increase in the efficiency of the engine and transmission, as well as fine-tuning of the chassis.

Visually they have aerodynamically optimised wheel housings and rear spoiler, low-rolling resistance tyres and each car is 15mm to 20mm lower than the standard production cars.

A gear-shift indicator inside tells the driver when to change up the six-speed gearbox for better economy, while both cars use stop-start technology as well.

Under the bonnet both the i30 and i10 use low-friction oil, an optimised cooling system and specific engine software controls that precisely monitor injection pressures and timing.

In European specifications, the new 66kW 1.6-litre CRDi turbo diesel engine in the i30 emits an impressively low 125g/km of CO2.

With the i-blue package, Hyundai has reduced this by 15.2 per cent, lowering the CO2 emissions to just 106g/km.

This reduction is also reflected in greater fuel efficiency. The i10 blue performs a similar role in reducing fuel consumption and cutting down on the level of harmful emissions.

Introduced in 2007, the i10 brought a new sophistication to the entry level of the Hyundai range in Europe.

The highly economic 55kW 1.1-litre CRDi five-door already has a very low emission level of just 114g/km CO2.

With the essential elements of the i-blue package, this can be reduced to just 95g/km, a meaningful 17 per cent reduction.

The i30 and the i10 will be joined by the i30 CW — Hyundai-speak for station wagon — as well as the performance Genesis coupe.

The 2009 Melbourne International Motor Show...