In flood-prone pastureland in Cumbria are 30,000 rapidly growing willow cuttings transforming a soggy Keswick field into a source of renewable energy.
Regional water firm, United Utilities, has been growing the willow for a year next to its Keswick wastewater treatment works with the aim of selling the harvest to the renewable energy market. The two hectares of land where the willow is planted is part of the natural flood plain of Bassenthwaite Lake and spends most winters under water, flooding the access track to Keswick wastewater treatment works and making the approach difficult.
United Utilities’ land agent, Caroline Holden, explained: “Short rotation coppice willow crops grow very fast and we have used it before to stabilise and re-profile river banks like Raisebeck, below Helvellyn, which was damaged in Storm Desmond.
“It’s a very effective, quick and permanent solution for natural flood management.
“The willow crop will help to take up some of the flood water and improve the biodiversity of the site by creating an early source of pollen for the bees and pollinating insects.
“We have never used SRC willow for biomass before but we’re hoping this could be the first of many sites near our sewage works which could be used in this way in the future,” she added.
Neil Watkins, from Energy Crops Consultancy, commented: “Perennial energy crops such as SRC willow wood crop are very beneficial for the environment by helping promote net-zero emissions, increased biodiversity and converting marginal land into profit.
“Planting SRC willow crop is a great way for farmers to make use of land and diversify their business to provide a valuable steady income in addition to enhancing food crops and livestock.
“At the same time, this source of biomass provides sustainable green energy, helping to turn the tide on the current climate emergency.”
Further south, United Utilities’ southern catchment team is partnering with a Cheshire farmer in a unique pilot to grow another energy crop in its groundwater safeguard zones as a way of reducing nitrates leaching into groundwater. The water firm has funded 70 per cent of the crop’s start-up costs, including purchase and planting of Miscanthus rhizomes on 10 hectares of catchment land, and will be monitoring the impact of the crop on nitrate leaching with porous pots. Miscanthus has the potential to give very high yields under UK conditions and can be used to produce heat, CHP or electric power on a range of scales from large power stations to small-scale biomass systems.
United Utilities’ catchment advisor, Vee Moore, explained: “Miscanthus has an excellent nutrient use efficiency. High yields can be achieved with little or no fertiliser use. Its extensive root system takes up nutrients, which are used for growth and, at the end of the growing season, recycled back into the rhizomes.”