Project Cavendish, Developing zero CO2 hydrogen combustion systems for heavy-duty commercial transport.

**Industry challenge**

Decarbonisation of heavy-duty vehicles is challenging due to demands on powertrain cost-performance, operational availability, design life and reliability, which are yet to be wholly met by any existing low carbon powertrain approach, such as fuel cells, battery electric or hybrid architectures.

Heavy-duty applications are much more sensitive to the specific operation-critical and cost-of-ownership characteristics of these technologies, creating uncertainty for UK-based OEMs trying to determine specific paths to zero-emissions.

The risks for OEMs, in terms of long-term security-of-supply, contribute to a resistance to adopting new low carbon technologies into vehicle launch plans, with significant impacts on the UK's decarbonisation trajectory. Currently, UK supply chains for systems and ancillaries in these segments focus very much on diesel heavy-duty applications.

**Opportunity**

Whilst heavy-duty powertrain roadmaps ultimately culminate in zero-emission hydrogen fuel cell and battery electric vehicles, long-term OEM strategies will remain critically-dependent on next-generation internal combustion engines (ICE) to meet OEM requirements, whilst reducing average fleet emissions in line with European CO2 legislation and meeting Euro VII levels of pollutant emissions. See appendix 3

Using hydrogen as a combustion fuel, so called H2-ICE, provides capability to meet heavy-duty/medium-duty requirements whilst delivering zero tank-to-tailpipe CO2 emissions.

However, traditional approaches to conversion of this fuel have meant significant engine redesign and associated need for manufacturing and assembly investment in the supply chain, providing inertia against conversion to hydrogen.

**Cavendish** **vision**

In response, the PHINIA group -- Fuel Systems (PHINIA Delphi UK Ltd.) & Hartridge -- their partners in the supply chain -- BorgWarner, MAHLE Powertrain and Cambustion -- and with simulation support from Oxford Brookes University, are pursuing a novel H2-ICE concept based on optimisation of existing heavy-duty diesel platforms to accommodate hydrogen as a fuel source, underpinned by novel fuel injection (PFI and HPDI options) and supporting turbocharger technology.

The consortium's approach therefore targets conversion (rather than replacement) of current heavy-duty engine platform designs -- incorporating novel injection technology options into standard perpendicular cylinder engine designs -- hence negating the need for significant supply chain manufacturing/assembly infrastructure investment (as would be required with a full engine redesign).

Conditional on achieving acceptable power density and thermal efficiency, developments can accelerate the adoption of H2-ICE and the displacement of diesel ICEs whilst safeguarding UK partners' positions in mature ICE-based supply chains.