An economic analysis of anaerobic digestate fuel pellet production: can digestate fuel pellets add value to existing operations?

Anaerobic digestion provides renewable energy through waste valorisation, but the digestate by-product is underutilised and presents a risk to water quality. Mechanical separation partitions phosphorous into solid fraction further processing fuel pellet can provide an additional source of revenue. Previous economic analyses looked only at aspects system (e.g. operational costs solely) requires investigation determine viability. In this paper, assessment production farm-scale anaerobic plants was carried out. The significance work comprehensive energy, phosphorous, balances involved in existing plants. aim paper financial viability with objectives compare two mechanical technologies: screw press, decanting centrifuge. Economies scale hold true for available typical UK farm-based (≤500 kWe) insufficient profitability, costing from £176/t (decanting centrifuge) £215/t (screw press), compared wood sale price £185/t. Increasing quantity by collaboration plant operators reduce cost between £95/t £121/t, improving increasing profit per head cattle 9–20% on dairy farm utilising digestion. has potential aid rural development while also protecting environment contributing diversification supply.