Volvo came up with a “Special Version” of the C30, appropriately calling it by the name of “Efficiency”. This version aims to be the flagship that will lead the fleet of Volvo cars in the future for the battle of fuel efficiency and clean exhausts.

“We are firmly committed to reducing the fuel consumption of our conventional petrol and diesel engines,” Volvo said about its upgrade of the Volvo auto parts for Efficiency.

Volvo is also concentrating on bio-fuels and hybrid technology and says energy-efficiency improvements are continuously being made to the company’s conventional drive trains. Coming soon, Volvo says, will be a Powershift gearbox that claims to reduce fuel consumption by about eight percent but, meanwhile, there’s the Efficiency which has taken fuel consumption below 4.5 litres/100 km and CO2 emissions to less than 120g/km

“This is a science of small adjustments and gains,” Magnus Jonsson, senior vice-president for research and development Volvo Cars said in an interview. “Many systems and details have been designed to suit all engine variants, from the smallest diesel to the most powerful petrol unit. This gives possibilities for fine adjustments to individual engine variants, particularly the smallest alternatives.”

So, the 1.6-litre Volvo C30 78kW turbodiesel engine comes complete with Volvo engine parts, which will become available in 2008 using at least 0.4 litres/100km less diesel and producing at least nine grams/100km less CO2.

“We are firmly committed to reducing the fuel consumption of our conventional petrol and diesel engines,” Jonsson said. “By doing this we will continuously reduce the overall CO2 emissions for our whole model range.”

The lower fuel consumption, he added, has been achieved through four main areas:

Aerodynamics - The Volvo Efficiency is lower, has a new rear roof spoiler, a new rear bumper, underbody panels, optimised engine cooling and aerodynamically optimized 16” rims.
Tires - Low rolling-resistance tires were included in the package.
Higher gearing - The unique gearbox variant has revised third, fourth and fifth gears.
Powertrain efficiency - This includes new low-friction transmission oil, optimization of steering servo assistance and engine management optimization.

The new Powershift gearbox will become available in Volvo C30, S40 and V50 units equipped with the two-liter turbodiesel (2.0D) engine. It has two manual gearboxes that work in parallel and are controlled by separate clutches. Since there is no disruption in torque delivery during the gear changing process, gearshifts are instantaneous and the efficiency rating is higher.

According to Volvo, they are working hard to improve other diesel engines and its petrol units. For the latter, the company’s experts are examining how direct fuel-injection technology can be further refined and are also looking at even more advanced control of the air/fuel mixture and valve control.

“When it comes to diesel engines, it isn’t fuel consumption that is the greatest challenge,” Jonsson said. “Here the main challenge is to meet the increasingly tough demands on regulated emissions such as nitrogen oxides and particulates without jeopardizing already low fuel consumption.”