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Raising a glass to whisky-powered renewable energy

Distilling bio-energy

Working with a large Scottish distillery, Veolia developed an innovative technology to recover energy from the by-products of whisky production. Distillation is an energy intensive process that traditionally relies on fossil fuels.

This means distillers are always looking for sustainable ways to deal with the waste they produce to improve their environmental footprint and save energy.

The organic by-products of whisky making (malt distilling and grain distilling) have great potential as a renewable energy source.

How it works
The 'spent wash' - a mixture of wheat, malted barley yeast and water - produced during distillation is separated into liquid and dried solids. The liquid is then converted, via anaerobic digestion, into biogas and the dried solids form a biomass fuel source.

Both the biomass and the biogas can be used to create renewable energy in the form of steam or electricity. We also treat the liquid to create clean water. All these resources (power, steam and water) are recycled back into the distillery, providing a sustainable production facility that minimises its impact on precious local resources.

When biomass is burned to generate renewable energy a solid ash is produced. This ash is rich in phosphate, an important non-renewable mineral that is used to produce fertilisers for the agricultural industry.