Cogeneration, which enables up to 85 per cent of the energy input to be converted into useful energy (much more than combined cycle power generation, the efficiency of which is close to 50 per cent), is still much below its potential, because the legal framework hindered self-generation (i.e. typically by the users themselves, such as solar panels in households) and the rates applied to large consumers of high voltage that were often subsidized. One third was used for domestic and rural activities in a fairly sustainable way, while the remainder was used for industrial purposes. While the overall chain of transformations and uses of wood in Brazil is poorly understood, it is clear that the overall efficiency of biomass is very low.