Cars run on anything these days: hydrogen; electricity; sugar cane ethanol. To the list can now be added whisky after a car successfully ran on biobutanol, a biofuel made from kernels of barley called draff and pot ale – a yeasty liquid residue produced during the fermentation process which makes the scotch. The whisky car is the brainchild of the clever folk at Celtic Renewables Ltd, who believe they have come up with a viable alternative to electric powered cars. For biobutanol can be used as a direct replacement for petrol and diesel without the need for modifications to be made to the engine. And the Edinburgh Napier University spinout believes the 750,000 tonnes of draff and two billion litres of pot ale that are produced by the malt whisky industry in Scotland every year would be enough to sustain an industry in Scotland worth £100m before moving on to other whisky-producing countries, such as Japan, India and the US. The government clearly likes the sound of that as it awarded the Edinburgh-based company a £9m grant to build a commercial demonstrator plant in Grangemouth, near Falkirk, which is expected to be fully operational by 2019. Celtic Renewables founder and president Prof Martin Tangney said, “What we developed was a process to combine the liquid with the solid, and used an entirely different traditional fermentation process called ABE, and it makes the chemical called biobutanol. And that is a direct replacement, here and now, for petrol”. He added, “This is the first time in history that a car has ever been driven with a biofuel produced from whisky production residues. It is fitting to do this historic drive in Scotland, which is famous not just for its world-renowned whisky but also for being a powerhouse for renewable energy.” Sounds like an occasion worthy of the finest malt.