TOKYO -- Japan's Mazda Motor and Nissan Motor are refining new technologies for internal combustion engines amid a global shift to electric cars. Japanese automakers expect to commercialize the technology and keep total carbon-dioxide emissions low.
"If we polish our internal combustion engines we could catch up with electric vehicles in terms of CO2 emissions," said Mitsuo Hitomi, managing executive officer of Mazda, at Automotive World in Tokyo in mid-January.
Assuming that electricity for charging electric vehicles will be sourced from thermal and other power plants, the average CO2 emissions per kilometer of Mazda's electric vehicles will be 130 grams, compared with gasoline cars' 148 grams.
Therefore, Mazda predicts that CO2 emissions will be similar to those of electric vehicles if fuel economy can be improved another 10% or more. They plan to achieve this by preventing losses by emissions and cooling of the engines. Mazda has developed the world's first commercially available compression-ignition gasoline engine, a technology used in diesel engines.
Automakers have been shifting their focus to electric vehicles since last year, in an effort to appeal their advanced technology to their consumers and shareholders. But not all vehicles will be electric.
Last July, Sweden's Volvo Car became the first major automaker to announce that it will go "all electric" from the cars it produces from 2019 onward, but that includes hybrids.
Private market research shows that while purely gasoline-powered cars are expected to decline gradually, vehicles called partial hybrids, which are driven by electric motors that assist internal combustion engines when driving at low speeds, are likely to increase.
Gasoline-powered cars, including full hybrids that are powered by electric motors when driving at slow speeds, are expected to still constitute nearly 90% of the market even after 10 years.
Toshihiro Hirai, Nissan's corporate vice president, has also vowed to expand electric vehicles and develop internal combustion engines. Nissan has its Leaf electric car brand, but has been unable to resolve technical problems of heavier vehicle weight with many batteries, said Hirai.
Nissan spent about 20 years to commercialize variable compression ratio engines for the first time in the world. Variable compression ratio engines -- which are designed to achieve optimal thermal efficiency by changing the piston movement smoothly depending on driving situation -- will be mounted on Nissan's Infiniti luxury brand.
Automakers are increasingly turning to electric vehicles, as the U.K., French and Chinese governments announced the tightening of regulations on gasoline and diesel cars. Toyota Motor plans to electrify half of its total vehicles by 2030. Other automakers also plan to boost electric vehicles and plug-in hybrids, as well as improve their internal combustion engines.
That said, the shift to electric vehicles will continue if environmental regulations are tightened globally at a faster pace than expected. Global automakers are under pressure to improve internal combustion engines to boost sales and boost fuel economy, and to shift managerial resources to technical development of electric vehicles.