Eco concerns over distillery biomass plants

A prominent Scottish farming group is calling for a moratorium on building large-scale biomass whisky waste converters over concerns that they could cause more environmental harm than good.

Diverting draff from the animal feed industry through the use of biomass converters could cause more environmental harm than good, a farming group claims

Addressing the Scottish government, which offers distillers financial incentives to adopt anaerobic digesters (AD) and biomass systems to convert whisky waste product into renewable energy, the Scottish Tenant Farmers Association (STFA) claims that the supply of draff, pot ale syrup and dark grains to the animal feed sector is now at risk.

While the STFA says it supports the principles behind the Scottish government’s Climate Change Plan, which encourages the use of anaerobic digesters and biomass plants in distilling, it says the government should look at the holistic impact of the policy rather than assessing environmental benefits in isolation.

Draff, pot ale and dark grains have been used by beef and sheep farmers in marginal areas for decades as a source of GM-free protein. The supply is now at risk, STFA says, because these byproducts are now processed by the increasingly prevalent “environmentally friendly” plant equipment.

As such, the price of draff has doubled in price, and dark grains are now transported by road from the Central Belt. In addition to the extra carbon emissions associated with haulage, the supply of dark grains is also coming under strain.

There are also concerns that the environmental impact of spreading the waste from the AD process on grassland as not been fully assessed.

“Unfortunately we are trying to close the stable door after the horse has bolted,” said Alastair Nairn, an STFA spokesperson on the environment and a north-east livestock farmer.

“It is more than five years since we highlighted the value of distillery by-products and warned the government of the damage that would be caused if supply became restricted.

“In 2012 a government-commissioned report by Scotland’s Rural College predicted that the expansion of whisky production would ensure a plentiful supply of draff and dark grains. This has proved to be wildly inaccurate. The explosion of AD and biomass over the last few years has all but decimated the supply of draff locally and dark grains now have to be hauled from the central belt.

“The growth of AD plants has created its own problems with a vast quantity of digestate [waste from the AD process] now having to be spread on grassland. As yet, farmers have no real idea of the long-term implications of spreading this waste and how it will effect the chemical composition of soils, trace elements and available nutrients.”

In 2015, a study from Zero Waste Scotland claimed that more than £272 million (US$340m) could be added to the Scottish economy each year if whisky waste was better managed.