Why Transitivity Matters in Road Transport Decarbonization

When anyone questions the origins of the impressive growth of China in the last thirty years, one of the typical answers is that China is run by engineers. Makes sense, doesn’t it? You do not build the workshop of the world if you do not have engineers. And engineering courses are mathematics heavy, and mathematics is the science that is used in all other sciences, even social ones. Transitivity is one of the basic relations you learn in algebra. I will stop my riddle right here and ask: why should transitivity matter to reduce the carbon footprint of road transport?

In the value chain of transport, fuel and engine complement each other, in Frank Sinatra-style: “you cannot have one without the other”, singing about horse and carriage, amongst others. Complement, as engines have been improved during the last century along the improvement of fuels, and vice-versa. The same is true for all emissions: NOx, particulates and greenhouse gas (GHG) emissions.

The overall performance of transport is the sum of emissions of the two successive steps of the chain: upstream, from Well to Tank (WtT), and downstream, from Tank to Wheel, Wing or Wake (TtW). And it is logical to assume that synergies will occur, minimizing emissions and maximizing efficiency, when co-designing and co-improving fuel and engine. So, if we want to assess the global environmental performance of the fuel-engine couples, we should measure on a Well-to-Wheel, Wing or Wake (WtW) basis. Pure transitivity.

At a Q8 service-station, a 100% HVO pump (Source: Neste)

Why then do we have distinct regulations in Europe, on fuel (in force: 2018/2001, Renewable Energy Directive, and 2009/30, Fuel Quality Directive) and on engine (in force: 2019/631 for light-duty vehicles, cars and vans, 2019/1242 for heavy-duty vehicles)? For the engine / vehicle regulations, the latest proposal is asking for zero GHG emission in 2035 for light-duty vehicles, which is a direct threat of internal combustion engine vehicles outright ban from new sales.

But, if you consider the possibility of a vehicle running on 100% renewable diesel (HVO) or on E85 ethanol-rich gasoline, some of these biofuels, using wastes and residues as raw materials for the production process, rightfully claim negative GHG emissions, thus giving the whole value chain a negative net climate contribution.

Don’t we face here a missed opportunity? Why are we ending up with such nonsense? Many answers come to mind:

• Intra-administration tug-of-wars: regulations, or part thereof, are under the responsibility of distinct European Commission Directorates-General (DG), like Energy, Transport, Climate. When more and more countries adopt the concept of a super-ministry covering the main sectors of importance for climate change or climate adaptation (ecology, energy, transport, agriculture, forestry, fisheries, the list is not exhaustive), the EU Commission still operates in watertight silos.

• Lack of co-operation between industrial sectors: There is the fuels industry on one hand, OEMs (engine, car and truck manufacturers) on the other. Doesn’t this limit the opportunity of mutual benefits? But such a co-operation has existed for a long time, if only to co-optimize the fuel-engine couple, with tremendous successes when looking at car mileage, increasing, or emissions of those pollutants so noxious in cities, decreasing. Not sure all OEMs share the Commission enthusiasm for all-out and breathtaking efforts in favor of electromobility, just listen to the Stellantis CEO for proof.

• Lack of consideration for technical issues: Coming back to the Chinese comment above, a scan of the biographies of the top executives, at commissioner and director-general level, of the key DGs listed above only show one mathematician among a pool of “soft” sciences graduates. Is Europe going the Anglo-Saxon way, lawyers everywhere?

• Biofuels fatigue: Biofuels, even advanced or synthetic, are seen by some as a thing of the past, burdened with controversies: the ghost of food v. fuel is back in the U.S. with the rise of raw materials prices in the post-pandemic period, the protection of biodiversity is high on the agenda, making the link to deforestation a real public opinion risk for anyone interested in forestry products or byproducts. Electromobility is “cool”, regardless of the price to pay, for all of us taxpayers in infrastructure investment and for the individuals in vehicle purchase and despite the current limitations (just look at the famous “rare” metals we do not have the capacity in terms of mining thereof, or at the availability and affordability of decarbonized electricity). Electric vehicles (EV) are emerging to last, and politicians pushing EVs will not be around to face the public backlash should promises not materialize. And hydrogen is even cooler, although even more remote in the future and uncertain in cost perspective: an even better silver bullet for the future, with no impact in real life, but the squandering of public money in R&D.

The jury will remain out, for some time at least, but a call to realism and pragmatism is necessary. Let us not forget we have readily available solutions, like biofuels, at hand to help us cope with our dwindling carbon budget, as un-cool they may be, and we should keep on repeating this inconvenient truth, education is repetition, after all.

Philippe Marchand is a Bioenergy Steering Committee Member of the European Technology and Innovation Platform (ETIP).