General Motors believes that petrol will be the fuel of choice for the vast majority of the world for the foreseeable future and is rolling out a new technologically advanced engine family to streamline its global powertrain portfolio with a modular architecture.

In its annual sustainability report, the US giant said this will enable a broad deployment across a variety of global markets and price points. Designed to achieve segment-leading efficiency, the new engines will power many of its highest-volume small cars and compact crossovers, including the next-generation Chevrolet Cruze, specifically tailored for China, which launched in 2014 as a 2015 model.

GM expects to build more than 2.5m of these engines around the world, introducing them across five GM brands and 27 models by the 2017 model year. This will lead to a GM engine portfolio that is considerably smaller, cleaner and more efficient than in the past without sacrificing performance.

The report stated: "The end result by 2017 will be a GM fleet that sets a new performance level in fuel economy and carbon emissions around the globe. Accordingly, the best way to realise a significant decrease in CO2 emissions in the short term is to put a meaningful number of fuel-efficient vehicles with traditional propulsion systems on the road."

At the same time, GM said it remains fully committed to the continued development of alternative fuel systems and advanced technologies, such as electrification, underscored by investment in an expanding portfolio of electric vehicles, but also by internal development and manufacturing capability for electric batteries, motors and power controls.

As of 2014, carbon-pricing schemes are expected to be operating in at least 33 countries and 18 subnational jurisdictions, covering around 20% of global emissions. Though CO2 pricing schemes vary widely around the world, all are intended to encourage consumers to purchase vehicles that emit less carbon or, at a minimum, to help raise public awareness about the importance of CO2 reduction.

GM said it has embedded institutionalised governance processes that predict, plan, measure and monitor its fleet's fuel economy and emissions performance on a dynamic and country by country basis, a complex task in which it has invested significant resources.

The report said: "To calculate the fuel economy for a single vehicle model in one market against multiple variables is complicated. Multiply that by dozens of models sold in nine markets with finalised regulation and two more with proposed regulation. The result is a fleet calculation with an enormously complex algorithm. These calculations and the subsequent plans around them, however, are now an intrinsic part of our business that impacts nearly every operational function from product development through delivery on a daily basis."