Abstract From a biophysical perspective, woody biomass resources are large enough to cover a substantial share of the world's primary energy consumption in 2050. However, these resources have alternative uses and their accessibility is limited, which tends to decrease their competitiveness with respect to other forms of energy. Hence, the key question of woody biomass use for energy is not the amount of resources, but rather their price. In this study we consider the question from the perspective of energy wood supply curves, which display the available amount of woody biomass for large-scale energy production at various hypothetical energy wood prices. These curves are estimated by the Global Biosphere Management Model (GLOBIOM), which is a global partial equilibrium model of forest and agricultural sectors. The global energy wood supply is estimated to be 0–23 Gm3/year (0–165 EJ/year) when energy wood prices vary in a range of 0–30$/GJ (0–216$/m3). If we add household fuelwood to energy wood, then woody biomass could satisfy 2–18% of world primary energy consumption in 2050. If primary forests are excluded from wood supply then the potential decreases up to 25%.