International Journal of Advances in Scientific Research and Engineering (ijasre) E-ISSN : 2454-8006 DOI: 10.31695/IJASRE.2019.33153 Volume 5, Issue 4 April - 2019 www.ijasre.net Page 133 Licensed Under Creative Commons Attribution CC BY Review on Current Global Geothermal Energy Potentials and the Future Prospects 1 Sani Aliyu and 2 M. M. Garba 1Department of Physics, Faculty of Science, Usmanu Danfodiyo University Sokoto, Nigeria. 2 Sokoto Energy Research Centre, Energy Commission of Nigeria, Usmanu Danfodiyo University Sokoto, Nigeria _______________________________________________________________________________________ ABSTRACT This paper examined the current Global Geothermal Energy Potentials and their future Prospects. The study assessed the global geothermal energy resources, their nature, extent of availability, estimated derivable electricity, current level of exploitation, and business opportunities available. The paper presented a historical perspective of geothermal extraction for power generation, industrial process heating and cooling of buildings. In the review, different techniques for converting geothermal energy into electrical power had been studied. The paper also reported a summary of the global geothermal energy usage. Keywords: Geothermal, Energy Potentials, Power generation. ________________________________________________________________________________________________________ 1. INTRODUCTION Energy is a critical issue for the survival of both developed and emerging economies. Globally, energy shortage remained a central bottle neck that hinders industrial and commercial developments, undermines economic growth, deters social development, and hinders overall human progress. In addressing the issues of security, increasing demand, and sustainability of energy, in recent years many countries worldwide have taken steps to increase the domestic energy security by supporting the development of their renewable energy resources including geothermal energy. Geothermal energy is thermal energy generated and stored in the Earth and originates from the original formation of the planet, from radioactive decay of minerals, from volcanic activity, and from solar energy absorbed by the surface (Think Global Green, 2008). The geothermal gradient, which is the difference in temperature between the core of the earth and its surface, drives a continuous conduction of thermal energy in the form of heat from the core to the surface. Geothermal energy is relatively cleaned, emission-free, renewable, solar energy derivative and economically friendly (Think Global Green, 2008). For many centuries man has taken advantage of geothermal energy for purposes such as cooking and bathing; for example, the Romans used waters heated by the earth in bathhouses (Climate Institute, 2008). An early example of commercial geothermal energy use took place in Idaho in 1890, when the Boise Water Works Company drilled wells to create a geothermal radiant heating system for the city. Hot water from the geothermal wells was piped into more than 200 homes and businesses; this system, as well as three newer versions, is still in use today (Idaho Department of Water Resources, 2007). Geothermal energy was first used to generate electricity in Larderello, Italy in 1904, when a turbine there lit five light bulbs (Renewable Energy UK, 2008). Presently, the U.S. has more geothermal electric generation capacity than any other nation. According to the Geothermal Energy Association (GEA), U.S. geothermal capacity stands at 3,086 MW (Bertani, 2010). The estimate of the current worldwide