► What does the future of engines look like?
► Synthetic, hybrid or both?
► Perhaps the BTCC has some answers
For 2025 the British Touring Car Championship is changing the basis of its technical regulations quite markedly. Instead of aiming to be more green by improving the efficiency of the cars, the new rules shift the responsibility for decarbonising to the fuel being used. In doing this it is actually quite far ahead of other international championships, such as F1 and its motorcycling equivalent, MotoGP, which will eventually take a similar route but not at such an accelerated rate.
The previous rules, which used hybrid engines as a way to reduce the CO2 emissions associated with running the series, were analogous to the EU’s use of legislation aimed at reducing tailpipe CO2 emissions for road cars. Unfortunately, the laws of thermodynamics mean you can never get to 100 per cent efficiency when you use an engine operating on a heat cycle, and so, as long as the fuel you are using in an engine has a proportion of fossil content, the vehicle will always emit some fossil CO2.
You can bypass this issue by using a fuel with no net CO2 emissions. To do this you have to ‘close the carbon cycle’, by taking CO2 already in the biosphere (so, not being dug out of the geosphere, which is what fossil fuel extraction is) and turning it into a fuel. This can be done using relatively straightforward biological process – making biofuel – but unfortunately there is a limit to how much such bio feedstock is available to do this. To go the whole distance on fully decarbonising fuel we need to use chemical approaches, and make ‘e-fuel’.
The e-fuel approach uses a chemical plant to combine non-fossil CO2 with hydrogen to make a fuel which, when burnt in a vehicle, has no net atmospheric CO2 impact. Ideal scenarios see the CO2 being extracted from the atmosphere and the hydrogen being obtained using electrolysis, with all the energy used being renewable or nuclear. The fuels will therefore be 100 per cent green, and you can make them have exactly the same characteristics as existing fossil fuels, with which they can be freely mixed.
Now, many will point out that moving vehicles about using a full e-fuel approach requires much more primary energy than if electrification is undertaken, and this is true. However, we have no shortage of renewable energy (solar energy impacting the Earth is over 1800 times what mankind uses for everything), so this should not be the primary consideration; the total cost of implementation is far more important. Because all of the feedstocks are free, there is no reason why eventually e-fuels cannot be as cheap as fossil fuels; and in any case we need them for aviation.
One of the great advantages of using e-fuel to decarbonise transport is that you change only one thing (the fuel, from fossil to net-zero-carbon e-fuel) and everything else stays the same, including the fuel distribution system and the vehicles, which already exist. Furthermore, the compatability of e-fuels with current engines and current fuels means we can head towards decarbonisation in an evolutionary way, not have to change everything at once, which is what battery electrification demands.
The fuel being used in BTCC is Hiperflo ECO102 R100 from Haltermann Carless. It won’t all be made using e-fuel processes but it will be 100 per cent renewable. It’s a step on the path to the full greening of motorsport, while being fully ‘e-fuel ready’. For BTCC (and F1 and MotoGP) this means racing can continue with combustion engines, which are pretty fundamental to the spectacle. It also means that regardless of (e-fuel) consumption, the racing has zero net carbon emissions – and so is environmentally directly comparable with Formula E.
It should also encourage a public debate on how we decarbonise transport. It’s a genuine solution to the massive problem we find ourselves in – and if it generates meaningful knowledge of e-fuels in the public consciousness, it could also save the European car industry.