A comprehensive review of geothermal cementing from well integrity perspective.

Geothermal energy is the thermal energy stored within earth. In other words, geothermal energy is the only alternative source of energy independent of the climate. This makes geothermal energy a more reliable source of energy which will help the world meet the minimum level of power demand. Although geothermal energy is independent of the climate, it is highly dependent on the underlying local, global, and hydrological frameworks. It is utilized for power (electricity) generation and/or directly used for heating purposes. While geothermal energy has a lot of potentials and is being utilized for more than a century, it faces several challenges which need to be addressed to make it more economical. This paper compares Oil and Gas well construction with Geothermal well construction to highlight the key differences between them. Furthermore, Geothermal cementing challenges are discussed in detail from a well integrity perspective. The impact of high temperature (up to 1000 °C), geothermal fluids, and corrosive gases (CO 2 and H 2 S) on geothermal cement are examined. The research and development carried out to mitigate these cementing challenges are meticulously reviewed and future research recommendations are presented. This review paper will not only help the Oil and Gas cementing personnel have an in-depth understanding of Geothermal cementing but also motivate them to use their expertise to solve the existing geothermal cementing challenges and accelerate energy transition process. • Detailed guide for Oil & Gas cementing personnel to understand the geothermal well construction challenges and solve them. • Focuses on geothermal cementing challenges, existing solutions, and its effect on long-term well integrity. • Review highlights the use of alternative cement systems with lower carbon footprints than the Portland cements. [ABSTRACT FROM AUTHOR]