Biomass is biological material from living (or recently living) organisms. In relation to energy, biomass is often plant based materials but can be from an animal source. When using biomass, there is a closed carbon cycle where no new carbon is added to the atmosphere. Biomass takes in carbon as it is grown (when referring to plant based biomass) and releases the same amount back into the atmosphere when used as fuel. When correctly managed, biomass is a sustainable fuel that could deliver a significant reduction in net carbon emissions when compared to fossil fuels.