As per the latest report, Automakers need to almost triple the pace of fuel economy improvements compared with the past 15 years to be back on track for net-zero emissions by 2050.
The fuel economy of the world’s cars and vans needs to improve massively in the coming years for the automotive industry to do its part to support global efforts to reduce greenhouse gas emissions. For battery electric and fuel cell electric vehicles, almost all the emissions are incurred in producing and delivering the electricity or hydrogen on which they run.
The analysis in the new report shows that in practically all countries in 2019, battery electric vehicles had the lowest emissions, followed by plug-in hybrids and hydrogen fuel cell electric vehicles. Hybrid vehicles have the lowest well-to-wheel emissions among vehicles with internal combustion engines using gasoline, diesel, or compressed natural gas. By 2030, the difference is set to be even starker because the production of electricity and hydrogen becomes less emissions-intensive as low-carbon sources increasingly displace fossil fuels.
Given slow progress to date, achieving this target will require fuel consumption to decrease by 4.3% per year on average from 2019 to 2030 – a near tripling of the average annual pace of improvement since 2005. Such a transformation in fuel consumption trends can be brought about only by stronger policies that increase the market shares of efficient electric cars as well as the global adoption of state-of-the-art efficiency technologies in internal combustion engines.
The importance of electric vehicles is underlined by the fact that CO2 emissions fell faster than fuel economy between 2017 and 2019 because market penetration of electric vehicles rose. Global average rated CO2 emissions in 2019 were 167 grams of CO2 per km (g CO2/km), a 1.6% decrease from 2017.
Hybrid electric vehicles deliver on average about one-third lower fuel consumption than conventional gasoline internal combustion engine vehicles and offer a cost-effective option to considerably improve the fuel economy of conventional vehicles. Battery electric vehicles achieve efficiencies two to four times higher than internal combustion engine vehicles, with zero tailpipe CO2 or pollutant emissions. The energy and fuel efficiency of plug-in hybrids are intermediate and depend critically on drivers’ charging and driving patterns. In 2019, only small shares of the light-duty vehicle market had been claimed by hybrid (3%), plug-in hybrid (1%), and battery electric vehicles (1%), so they had little impact on overall emissions performance. But this is likely to change over the current decade.
Rapid deployment of renewables and other low-carbon power generation and hydrogen production technologies are the foundation for decarbonization across the energy sector (and not only for zero-tailpipe-emission light-duty vehicles). In all regions and in all scenarios, the tank-to-wheel emissions of electricity decrease by 2030.
Battery electric vehicles have the lowest emissions, followed by plug-in hybrids and hydrogen fuel cell electric vehicles. Hybrid vehicles have the lowest well-to-wheel emissions among compressed natural gas, diesel, and gasoline internal combustion engines.
This rank order does not hold across all regions and all scenarios. In the Stated Policies Scenario, hybrid vehicles can emit less than battery electric vehicles sold in 2019 in those regions in which the electricity mix relies particularly heavily on coal, although this is set to change as governments continue to adopt additional policies to decarbonize the power sector as a means to meet their long-term decarbonization targets.
This is reflected by the Announced Pledges Scenario, in which battery electric vehicles offer the deepest carbon reductions on a well-to-wheel basis in every instance, thanks to rapid reductions in the carbon intensity of electricity generation. The clear coupling between power sector decarbonization and battery electric vehicles provides a strong rationale for promoting battery electric vehicles as a technology for decarbonizing light-duty vehicle operations to meet climate ambitions.
The well-to-wheel greenhouse gas emissions of fuel cell electric vehicles vary depending mainly on how hydrogen is produced. Currently, well-to-wheel emissions of fuel cell vehicles driving on hydrogen produced via coal gasification can be as high as those of gasoline internal combustion engine vehicles, while those using hydrogen from natural gas steam methane reformation achieve well-to-wheel greenhouse gas emissions on par with hybrid electric vehicles.
Policies promoting plug-in hybrid electric vehicles need to encourage charging and driving patterns that realize these vehicles’ full potential to reduce greenhouse gas and pollutant emissions. Trip-making and charging patterns can have a substantial impact on real-world plug-in hybrid fuel economy and electricity, resulting in wide variability between rated and real-world performance. The key to ensuring that plug-in hybrids are driven on electricity will be to tie regulations and incentives more closely to real-world performance.