The potential for bioenergy is inherently limited by the amount of biomass that can be produced sustainably without impacting food supplies, degrading farm land, or destroying pristine ecosystems. In order to explore this potential, two German scientists investigated the feasibility of replacing fossil fuels with biomass as the primary energy supply.
Their paper, published in the journal Naturwissenschaften, posited a scenario in which degraded lands were planted with fast growing trees, which were then harvested, converted via fast pyrolysis into a liquid bioslurry, and transported similarly to petroleum. This bioslurry could then be refined into transportation fuels and biobased chemicals, or used in the production of heat and power. By relying on degraded and non-productive land, this scenario avoids concerns regarding deforestation or competition with food production. According to the authors, "A high percentage of these degraded areas should be available and suited for afforestation…To combat ongoing desertification and to improve the fertility of soils, it would be in the objective interest of the respective countries, of the local population, and in the general interest of mankind to afforest these degraded areas and to use the biomass continuously for the production of the necessary energy, fuel, materials, and chemicals of the respective country and, if possible, for export."
The study found that biomass produced in this manner could fully replace fossil and nuclear energy in 2030, using demand as forecast by the International Energy Agency (IEA). Furthermore, this source of energy would be cost effective (on par with coal and cheaper than nuclear) and have a number of secondary ecosystem benefits, including habitat improvement, soil conservation, and water quality improvement.