A renewable energy scheme which absorbs brewery waste has claimed its innovative technology could play a significant role in rectifying Ireland's record of pollution control, writes Iva Pocock.
Supported by the Environmental Protection Agency, Wicklow County Council and the Wicklow Rural Partnership, the Clearpower energy scheme has this year bio-filtered 1,000 tonnes of brewery waste through the roots of trees.
The development could significantly help Ireland to implement overdue EU environmental directives, said Clearpower's managing director, Mr Simon Dick.
"What we have is a technique which disposes of waste while fertilising an energy crop thus increasing the yield of valuable wood chip that can be used for renewable energy," said Mr Dick.
"This is a much more controlled technology than widespread landspreading which is so problematic with the EU Commission."
Some 50 hectares of willow in counties Wicklow, Kildare and Kilkenny have been cultivated using the ancient technique of coppicing, whereby year-old stems are cut back at the base, producing multiple shoots and a dense root system.
The rows of willow are interspersed with 3½ kilometres of piping which disperse the liquid brewery waste through a drip-feed system.
"It's certainly a very innovative project," said Mr Brian Kehoe, programme manager with the Wicklow Rural Partnership. "When someone is prepared to take a risk, especially involving alternative land use, that's where we come in."
The Clearpower renewable energy scheme has been monitoring the environmental effects of pumping 1,000 tonnes of weak worts, the liquid from soaked ground malt, through their willows. "Our results show that there has been no significant change in the soil or surrounding water," said Mr Dick.
The advantages of using short rotation coppice (SRC) willow as a biofilter include the recycling of nutrients, reduced health hazards as it is a non-food crop and higher profitability to growers due to reduced fertiliser costs, he added.
Waste from other food processors, fish farms and textile production could also be effectively treated by biofiltration, claimed Mr Dick.
Mr Malcolm Dawson, from the Northern Ireland Department of Agriculture and Rural Development, believes the bio-filtration capabilities of willow are one of the reasons SRC willow will increase in Ireland, irrespective of Government financial supports for energy crops.
"I am totally confident SCR will happen, particularly because the climate and soils of Ireland are so suited to growing willow."
SRC willow is just one source of energy from plants, known as biomass, which are promoted by the Irish BioEnergy Association.