An onsite bioenergy plant commissioned one year ago at Diageo’s Glendullan distillery in Speyside, Scotland, is now converting approximately 1,000 cubic meters (1,307 cubic yards) per day of malt whisky distillery byproducts into energy. That rate of production equates to about 1 million cubic meters (1.3 million cubic yards) of biogas per year, producing 6,000 megawatt hours of thermal energy for the distillery.
The anaerobic digestion (AD) plant was designed and installed by Cambridge, England-based Clearfleau. The Glendullan distillery produces Glendullan single-malt scotch whisky.
The plant is delivering a 25 percent reduction in fossil fuel energy demand at the distillery, according to Clearfleau, saving Diageo significant costs and reducing its carbon footprint by 1,000 metric tons of CO2 per year.
Clearfleau says it collaborated closely with global distiller Diageo in developing the bioenergy plant at Glendullan and an earlier plant at the nearby Dailuaine distillery, which has been operational for more than three years. Each onsite plant has a “high-rate digester, specifically designed to handle liquid distillery co-products, followed by aerobic treatment for water cleanup,” according to Clearfleau.
The AD plants reduce the incoming COD (chemical oxygen demand) load by more than 95 percent and minimize further treatment required for the discharge of filtered water to nearby rivers, according to Clearfleau.
“We are working with Diageo and other distillers to deliver renewable energy solutions that support carbon reduction targets and a more circular approach to resource use,” says Craig Chapman, chief executive of Clearfleau.
