While powertrain electrification offers significant opportunities to reduce vehicle emissions in the urban environment, the gasoline engine is likely to continue to play a significant role in passenger cars—both in conventional and hybrid powertrains—for many years to come. This is particularly the case for mid- to premium-sized passenger cars that are used for longer-distance journeys.

Furthermore, in parallel with efforts to improve the efficiency and reduce the CO₂ emissions from such vehicles, there is growing recognition that a potential engine development challenge exists in the form of particle emission numbers below the current ⌀ 23 nm threshold.

Through the use of state-of-the-art development techniques, such as optically accessed single cylinder engines, a range of modelling and simulation tools and the application of novel engine componentry, the optimal trade-offs between cleanliness and efficiency are being identified for such next-generation gasoline engines.

The results of this work will be used for the creation of two demonstration vehicles, which will be powered by gasoline engines yet to be introduced to the market. It is intended that the two vehicles will use contrasting approaches to achieving the project targets, they will use different new combustion systems, fuel injection and dilutent technologies (e.g. lean operation or water injection), ignition systems, engine air handling systems and aftertreatment packages.

Progress on the project is already offering insights into the best way forward in meeting emissions and efficiency requirements for comparable gasoline engines over the coming decade.

As PaREGEn aims to assess the emissions of particles as small as 10 nm in size (compared to the current regulatory threshold of 23 nm), the project intends to use the latest measurement equipment as derived from the ongoing research projects, which are investigating testing technologies and methodologies for nanoparticle measurement, such as DownToTen and PEMS4Nano.

Ricardo is pleased to be coordinating and working as part of the 16-member PaREGEn consortium, including key automotive industry partners such as Daimler, Jaguar Land Rover, Bosch, Johnson Matthey, IDIADA, FEV, Honeywell, LOGE AB, Siemens Industry Software and UFI Filters.Ensuring that the next generation of gasoline combustion engines makes advances in fuel efficiency and CO2 reduction, whilst also limiting nanoparticle emissions, is an imperative for the automotive industry. I am pleased that we will be welcoming all members of the PaREGEn consortium to the second General Assembly of the project, to be hosted at the Ricardo Centenary Innovation Centre at Shoreham-by-Sea, UK, in June, when we will review the first nine months’ progress and confirm plans for the coming year.

—Simon Edwards, Ricardo global technology director

If adopted across all light vehicles, these short term engine innovations would reduce the EU vehicle parc emissions by ~2MtCO₂ in 2025, and < 10MtcO₂ and approximately 10% PN > 10nm in 2030, the consortium partners said.