Biofuel from whisky by-products

Edinburgh Napier University researchers developed the new biofuel over the last two years, with the help of a £260,000 Proof of Concept research grant from Scottish Enterprise.

The team focused on the two main by-products of whisky production - ’pot ale’, the liquid from the copper stills, and ’draff’, the spent grains - as the raw material for producing the butanol fuel. As part of their research, the researchers were provided with samples of whisky distilling by-products from Diageo’s Glenkinchie Distillery.

With 1,600m litres of pot ale and 187,000 tonnes of draff produced by the malt whisky industry annually, the researchers believe that there is real potential for the biofuel to be available at local garage forecourts alongside traditional fuels.

Unlike ethanol, the nature of the biofuel means that ordinary cars could use it instead of traditional petrol. The product can also be used to make other green renewable bio-chemicals, such as acetone.

The university now plans to create a spin-out company to take the new fuel to market and leverage the commercial opportunity, in a bid to make it available at petrol pumps.

Prof Martin Tangney, director of the Biofuel Research Centre at Edinburgh Napier University, is leading the research. He said: ’While some energy companies are growing crops specifically to generate biofuel, we are investigating excess materials such as whisky by-products to develop them. This is a more environmentally sustainable option and potentially offers new revenue on the back of one Scotland’s biggest industries.’

The technology for developing bio-fuel from whisky was inspired from a 100 year old process created by Chaim Weizmann, a Jewish refugee chemist in Manchester who studied the butanol fermentation process initially as part of a programme to produce rubber synthetically. The process was then used in explosives manufacture during both WWI and WWII.