Back in March of 2021, Audi announced it was halting the development of new combustion engines. The firm has now taken a step further toward its “vision of carbon-neutral mobility’ by approving many of its current six-cylinder diesel engines for use with the renewable fuel HVO (hydrotreated vegetable oil).
The company has ambitious plans to become carbon-neutral by 2050.
V6 engines on renewable fuels
“We’re optimizing our existing combustion engine portfolio for more efficiency and lower emissions. One way we’re doing this is by creating the requisite technical foundations for the use of sustainable fuels such as HVO,” said Oliver Hoffmann, Chief Development Officer at Audi.
The models to soon run on HVO are the A4, A5, A6, A7, A8, and the Q7 and Q8 SUVs. The Q5 will also be added to that list at the start of March and will be followed by the A6 Allroad in the summer. With this new option, Audi hopes to reduce CO2 emissions by 70-95 percent compared to diesel vehicles.
But that is not the only benefit of running on HVO. There’s also the fact that the fuel has a significantly higher cetane rating, which will result in more efficient and cleaner combustion in comparison to conventional diesel engines.
“As the cetane rating of HVO is around 30 percent higher, the combustibility of the engines is enhanced. The positive effects of this are particularly noticeable when the cold starts. We tested the effects on various components, the performance, and exhaust emissions in specific validation run before granting approval,” added Matthias Schober, head of powertrain development for V-TFSI, TDI, and PHEV at Audi.
HVO and its advantages
HVO is a renewable biofuel created from excess or waste materials such as vegetable oils from the food sector or agricultural residue. The material is converted into aliphatic hydrogen by combining these substances with hydrogen. Aliphatic hydrogen is compatible with diesel engines and can replace fossil elements in fuels, blended with conventional diesel fuel, or utilized as a pure fuel on its own.
Utilizing HVO instead of conventional diesel is beneficial for reduced CO2 emissions, cleaner combustion, and increased combustion efficiency.