Why Synthetic Fuels Still Won’t Save Internal Combustion In Cars

Breakthroughs in synthetic fuel technology should have raised eyebrows among any self-respecting petrolhead. The idea, evidenced this week by Porsche’s eFuel activities in Chile, is that we can generate the same lovely power figures and greater thermal efficiency while producing much less carbon dioxide and almost none of the harmful particulates emitted by exploding fossil fuels. Brilliant! But wait.

While Porsche plans to introduce them into its motorsport programmes and experience centres, with a view to potential road-going applications, a new report from engineering expert Ricardo (builders of McLaren’s V8s, among many other things) says a large-scale adoption of the technology in road cars is best avoided in favour of “more efficient” solutions.

Such reports are usually snappily-named, and this gem is no exception. ‘Renewable electricity requirements to decarbonise transport in Europe with electric vehicles, hydrogen and electrofuels’ was produced on behalf of Transport & Environment, a European campaign group focused on cleaner transport. Ricardo’s conclusions make dismal reading for anyone hoping for a lengthy stay of execution for new combustion engines.

Top of the list of its findings is that direct electrification is the best way to reduce carbon emissions from cars between now and 2030. The report doesn’t look much beyond how effective the various technological paths are in terms of reducing emissions, so the usual caveats still apply to mass adoption of BEVs, but Ricardo essentially says the faster we all convert to battery-powered cars, the better, at least in terms of street level emissions.

Interestingly, the study also looks at how much renewable electricity is needed for all this, the assumption being that we aim to move towards 100 per cent renewable power for everything in order to factor-out the extremely high carbon emissions involving in manufacturing BEVs. As such, a lot of the numbers are based on forecasts and best-case guesstimation. Ricardo believes there’s enough potential renewable energy capacity in Europe to effectively decarbonise road, air and shipping transport by 2050, but only if someone comes up with effective zero-carbon solutions for how to power the big stuff like aircraft and ships. Don’t want to hit an unexpectedly strong headwind and run out of battery charge somewhere over the Pacific, do we?

By 2050, Europe will need about 2800 Terawatt-hours (TW/h) of renewable juice to supply the transport industry, says Ricardo. The pan-continental potential for generation across solar, wind and geothermal is up to 28,000TW/h. In theory, then, it’s possible to target a fully renewable energy supply within decades and Ricardo says the most efficient way to power cars is via batteries that can directly accept the generated power rather than wasting that same energy cracking usable hydrogen or manufacturing synthetic fuel.

As obviously biased as Transport & Environment is, as an entity, the logic is solid. Efficiency everywhere will hopefully help humans achieve some sort of balance with the natural world, unless nothing is done about global population growth, in which case this is all futile and we may as well all get ourselves some rollin’ coal.

It’s not that there’s no future for synthetic fuels; it’s just not likely to be a future that sparks a new era of investment in ICE. The fuels will eventually need to be targeted at existing combustion-driven cars, fully compatible with their technology and cheap enough not to penalise those people who can’t afford the (currently) off-putting expense of buying or financing a family-sized electric car. It’s a realistic and effective way of lowering the emissions of fossil fuel-powered vehicles, but it’s really only a twilight-hours mitigation. The revolution will still be measured in volts.