Flexible Clean Propulsion Technologies
Project
The Flexible Clean Propulsion Technologies (Flex-CPT) project is uniquely positioned to overcome the challenges en route to zero-emission marine and off-road transport. Its goal is to establish an economically stable, zero-emission future for the Finnish powertrain industry, departing boldly from locally driven, single-fuel agendas.
The project acknowledges that effective decarbonisation means embracing all new zero-carbon fuel options, like hydrogen and ammonia, alongside more mature low-carbon choices such as methane, methanol and biodiesels. This level of multi-fuel integration is an unparalleled technological challenge for powertrain development.
The Flex-CPT project aims to demonstrate robust powertrains achieving up to 100% reduction in tailpipe greenhouse gas emissions, optimising individual fuel streams according to availability, pricing, combustion efficiency and emissions. The project will use fuel-agnostic combustion and aftertreatment, supported by complementary electrification, to accommodate five enabling fuel categories within just two versatile engine platforms. These will handle a wide range of power demands for off-road and marine transport, with minimal hardware adjustments. Fuel-quality adaptive control functions and self-learning capabilities will help address multi-fuel calibration complexity.
The Flex-CPT research plan incorporates 33 innovations, ranging from fuel reforming-based reactivity on demand and adaptive aftertreatment deposit formation control, through to thermal management of hybrid systems exploiting the synergy of fuel storage technology with electrification.
The project content is grouped into five techno-economical work packages (WP1- WP5), with a separate one (WP0), committed to project management.
WP Leader: Merja Kangasjärvi and Aino Myllykangas, University of Vaasa
Research organizations: All consortium members.
Companies: All consortium members.
WP0 focuses on efficient project management and assisting other WPs and company projects achieve their goals. WP Leaders act as Project Managers. Their responsibilities include project administration, internal communication and external dissemination of the project:
- Project administration – management routines, processes and tools; consortium agreement and other common documents; monitoring the achievement of project objectives; communication between the consortium and Business Finland, etc.
- Internal communication – organising project-level events; managing a communication platform; acting as contact people for the consortium, etc.
- External dissemination – project website; social media; press releases; newsletters; dissemination materials, etc.
WP Leader: Maciej Mikulski, University of Vaasa
Research organisations: University of Vaasa; Aalto University; Åbo Akademi University; VTT Technical Research Centre of Finland; University of Turku
Companies: Wärtsilä; AGCO Power
International collaboration partners: Lund University (Sweden); Lublin University of Technology (Poland); Hitit University (Türkiye)
We develop multi-fuel powertrain capabilities—the core objective of the project—by advancing co-combustion solutions for gaseous fuels of varying compositions. Building on the next-generation marine engine platform, which incorporates reactivity-controlled compression ignition (RCCI) and variable valve actuation (VVA) technologies, we focus on the flexible integration of hydrogen and onboard reformed ammonia into the existing natural gas baseline.
This is achieved through an innovative virtual development framework which leverages fast, predictive models. These allow efficient development of the enabling control solutions and reduce experimental calibration efforts.
Tasks:
Task 1.1 Model-based multi-fuel engine development
Task 1.2 Fuel-flexible control
Task 1.3 Multi-fuel engine calibration
Task 1.4 Fundamental considerations for multi-fuel combustion
Solutions:
S1. Innovative reactivity on demand concept for multi-fuel control – proof of concept in model-in-the-loop (MIL)
S2. New use of vibration measurements as virtual sensors for combustion control in multi-fuel engines
S3. Multiple input, multiple output (MIMO)-based and adaptive multi-fuel (three-stream) combustion control implemented on the RCCI engine platform
S4. Self-learning RCCI engine with local on-board extremum-seeking, improving efficiency and emission over lifetime
S5. Advanced design of experiments (DOE) methodology to cut the carbon footprint of experimental engine optimisation by 30% compared with the industry state-of-the-art
S6. Full-factorial, multi-fuel hydrogen-NG calibration implementable in cutting-edge RCCI engine platforms
S7. Emission-compliant RCCI engine demonstration working with hydrogen admixtures up to 80%
S8. New fundamental knowledge on the influence of hot source and lubrication oil-induced auto-ignition in lean-burn, multi-fuel gas engines
S9. Fundamental understanding of multi-fuel RCCI-type combustion by detailed reactive large eddy simulations (LES)
WP Leader: Rasmus Pettinen, VTT Technical Research Centre of Finland
Research organisations: VTT Technical Research Centre of Finland; University of Vaasa; Aalto University
Companies: Wärtsilä; AGCO Power
International collaboration partners: Lund University (Sweden); IEA AMF TCP (International Energy Agency Technology Collaboration Platform on Advanced Motor Fuels)
The primary objective of WP2 is to establish feasible multi-fuel solutions reducing CO₂ emissions in high-speed engines from both WTW (well-to-wheel) and TTW (tank-to-wheel) perspectives. We adapt and develop efficient, low-emission combustion concepts capable of utilising carbon-free hydrogen and renewable liquid fuels within the same baseline engine platform.
WP2 addresses key challenges associated with both fuel types through a combination of simulation and experimental work. The focus for hydrogen is on enhancing combustion stability, mitigating blow-by gases and deepening the understanding of fundamental combustion characteristics across various modes. Methanol will be studied as a neat fuel in spark ignition (SI) mode, in dual-fuel applications and as a blend with renewable diesel. By covering a wide range of technical solutions, WP2 provides a fast track for effectively reducing CO₂ emissions from high-speed engines, in different operating scenarios.
Tasks:
Task 2.1 Flexible H2 combustion
Task 2.2 Flexible methanol combustion concepts
Solutions:
S1. Pre-calibration for retrofitting a conventional diesel engine to run on low-carbon methanol blends
S2. New methods for reducing H2 blow-by gases and ventilating the crankcase for explosion prevention
S3. Innovative methods for fast simulation of the blow-by gas via a coupling of the cylinder and piston-ring pack model
S4. Solutions for improving cold-start characteristics of methanol-fuelled engines in NRMM applications
S5. Novel combustion concepts for methanol combustion in SI-engines for non-road mobile machinery (NRMM) applications
S6. Stable combustion concepts for H2
WP Leader: Katriina Sirviö, University of Vaasa
Research organisations: University of Vaasa; Åbo Akademi University; VTT Technical Research Centre of Finland; University of Oulu
Companies: Wärtsilä; Meyer Turku; AGCO Power; Neste; Hycamite
International collaboration partners: University of Cyprus (Cyprus); Wuhan University of Technology (China); University of Agder (Norway); Korea Advanced Institute of Science & Technology – KAIST (South Korea)
WP3 investigates the feasibility of carbon-neutral fuels and their impact on marine and non-road applications. The focus is on compliance with emerging regulations, storage compatibility, life cycle analysis (LCA) and sensitivity studies on greenhouse gas emissions to determine CO₂-equivalent limits for each fuel. In this context, we assess the feasibility of carbon capture and utilisation (CCU) in engine applications, including storage challenges and the compatibility of existing engine components with new fuels and blends.
Tailor-made blends play a pivotal role in optimising engine efficiency and emissions, especially in kinetically-controlled combustion concepts. To this end, WP3 develops new metrics for fuel reactivity and investigates additives which enhance ignition performance. Both aspects are critical for developing multi-fuel combustion control and extending the limits of low-temperature combustion (LTC).
Tasks:
Task 3.1 Impact assessment of new fuel options
Task 3.2 Fuel compatibility, storing and blending
Task 3.3 Ignition improver study; low-temperature combustion and new fuels
Solutions:
S1: Method for assessing fuel-dependent total cost of ownership in marine and off-road applications
S2: Knowledge on the potential to install a CCU unit and to convert CO2 back to a fuel compound in-situ
S3: New laboratory method for analysing fuel and material compatibility for a broad fuel portfolio
S4: Guidelines for designing and operating tanks for carbon-neutral fuel and fuel blends
S5: New laboratory method for analysing fuel blend composition, taking account of unlegislated fuels
S6: New dedicated metrics to determine the reactivity of fuels in LTC
WP Leader: Mika Huuhtanen, University of Oulu
Research organisations: University of Vaasa; VTT Technical Research Centre of Finland; University of Oulu; University of Turku; Åbo Akademi University; Aalto University
Companies: Wärtsilä; Proventia; AGCO Power; Meriaura
International collaboration partners: University of Cyprus (Cyprus); Université Claude Bernard Lyon (France); IEA AMF TCP (International Energy Agency Technology Collaboration Platform on Advanced Motor Fuels)
WP4 concentrates on research and development of aftertreatment systems for emission abatement, particularly in multi-fuel settings, and focusing on ammonia- and methanol- fuelled engines. These fuels carry the greatest additional challenge for multi-fuel combustion solutions. There is special emphasis on exploring aftertreatment configurations suitable for next generation low-temperature multi-fuel combustion concepts.
The main tasks in WP4 are: 1) Determine urea deposit formation in different conditions in engine experiments, and develop fast urea deposit detection methods and models. 2) Develop aftertreatment measurements and testing, as well as study aftertreatment catalysts for ammonia- and methanol-fuelled engines. Studies include the deactivation effect of impurities present, such as those in green fuels. 3) Development of an ATS control system with enhanced predictivity. 4) Development of an accelerated, rapid ageing procedure to ensure long term performance of aftertreatment systems (DPFs and SCRs).
Tasks:
Task 4.1 Urea deposit formation control for multi-fuel engine
Task 4.2 Development and design of ATS for engines running green fuels
Task 4.3 Development of ATS control techniques for multi-fuel and ammonia engines
Task 4.4 Rapid ageing procedure to ensure long-term ATS performance; focus on DPF and SCR
Solutions:
S1: New method to predict and control urea deposit formation
S2: Further development of an online optical deposit measurement sensor
S3: New model to spray AdBlue to avoid wall-wetting and improve catalytic converter performance
S4: Improve reduction of NOx and N2O emissions over wide temperature range with novel catalysts
S5: Combination of engine, catalyst and control understanding improves the control of ATS
S6: New accelerated ageing procedure proven to simulate aftertreatment ageing in normal field use
WP Leader: Pasi Peltoniemi, LUT University
Research organisations: LUT University; Aalto University; VTT Technical Research Centre of Finland; Tampere University; University of Vaasa
Companies: AGCO Power; Meyer Turku; Wärtsilä; Lumikko; Bosch Rexroth
International collaboration partners: Politecnico di Torino (Italy); Arizona State University (USA); Karlsruhe Institute of Technology/ Institute for Vehicle Systems Engineering (Germany)
WP5 focuses on hybrid-electric solutions using multi-fuel powertrains that are applied in non-road mobile machines (NRMM) and marine applications. The key research themes focus in the areas of thermal management challenges in NRMM, power and energy management methods for battery hybrid powertrain using flexible fuel capable RCCI engine, and topics related to battery operations such as battery charging and battery lifetime modelling and estimation. Due to the high power and high energy requirement across the marine and NRMM applications it is seen that multi-fuel hybrid-electric solutions enable to reach to level of future requirements for emissions and also performance.
Tasks:
Task 5.1 Thermal management for non-road mobile machinery (NRMM) powertrains
Task 5.2 Power & energy management solutions
Task 5.3 Battery operations in hybrid systems
Solutions:
S1: Optimal thermal management concept for NRMM use
S2: Thermoelectric generation for NRMM
S3: Passive thermal management methods and concept for batteries
S4: Control concept for battery + RCCI engine
S5: Lifetime model for battery energy storage
S6: Onboard charger concept for NRMM
