Abstract Geothermal energy is a technically-proven, cost effective source of electrical and thermal energy that has been utilized for many decades. Recent estimates indicate that over 6700 MWe (megawatts electrical) and 8200 MWt (megawatts thermal) are currently developed throughout the world. This paper discusses the specific environmental advantages to the development of geothermal electrical power and direct use projects and demonstrates how environmental impacts can be easily mitigated using existing technologies. In the areas of CO 2, NO x, and SO 2 emissions, land disturbance per MWe and disposal of waste products, geothermal energy has significantly fewer impacts than most other energy sources, particularly conventional fossil and nuclear fuels. Examples are sited where geothermal developments have occurred in pristine areas with no significant impacts and even offering the opportunity for improving environmental conditions. There is a strong need for energy policy makers throughout the world to recognize the environmental advantages of geothermal energy and to incorporate their economic value when pricing and selecting new sources of energy.