Fig. 1From: Implementation of voluntary verification of sustainability for solid biomass—a case study from DenmarkConsumption of solid biomass (wood chips, wood pellets and wood waste) in the energy sector in Denmark 1975–2017 (a), and domestic production and import of solid biomass (wood chips, wood pellets, wood waste and firewood) in Denmark 1975–2017 (b). Adapted from Energistyrelsen [38]Back to article page