The proposed project will integrate Libertine's 'intelliGEN' Opposed Free Piston development platform together with subcontractor MAHLE Powertrain's Flexible ECU (MFE) within an engine test cell at MAHLE Powertrain's facility in Northampton, to demonstrate a first-of-a kind variable compression ratio combustion development engine for renewable fuels. The first demonstration fuel will be bioethanol, a low carbon fuel that can be produced from renewable resources including agricultural wastes and residues. During phase 1 Libertine will make plans with MAHLE Powertrain and prospective OEM clients for phase 2, to build a prototype and test it in real world scenarios. In a free piston engine, the crankshaft is replaced by high performance linear electrical machines permitting engine manufacturers to dispense with the crankshaft mechanism in future internal combustion engines. In its place, Libertine's linear electric machines will allow electronic piston motion control to deliver real-time variable compression ratio, providing optimum combustion conditions in every combustion event -- whether during cold-starts, peak power or peak efficiency operating modes, even if the fuel blend in the tank changes with every fill. The variable compression ratio and non-sinusoidal piston motion capabilities of Free Piston Engines allow cleaner and more efficient utilisation of renewable and synthetic low carbon fuels owing to the combustion characteristics of several of these new fuels. Libertine's intelliGEN Opposed Free Piston development engine systems provide the means for OEMs to develop new products to make full use of synthetic, low carbon and renewable fuels. These products will be essential for the decarbonisation of 'hard to electrify' transport applications including light and medium duty commercial vehicles, for a proportion of passenger automotive market where vehicle use and recharging constraints are a barrier to electrification, and for a larger range of distributed power generation applications.