A survey of geothermal power generation combined with renewable energy for low carbon emissions

At present, industrial development is heavily dependent on traditional fossil energy, which has had an increasingly serious impact on the environment. Clean and renewable energy has received extensive attention and its proportion in daily life has gradually increased. As a clean and renewable energy source that is not affected by changes in weather and seasons, geothermal energy has developed rapidly in recent years and has received increasing attention. According to reports, the total installed capacity of geothermal power generation in the world in 2020 was 15 950 MW—an increase of ~27% over 2015. At the end of 2019, the total installed capacity for global geothermal direct use was 107 727 MW—an increase of 52.0% compared with 2015; the total annual energy use was 1 020 887 TJ (283 580 GWh)—an increase of 72.3% over 2015. Through the investigation of geothermal power generation technology in recent years, the characteristics and shortcomings of various power generation methods are analysed. At the same time, this review analyzes the characteristics of geothermal energy and other renewable-energy (solar energy, water energy) coupling power generation, and analyzes the principles and characteristics of geothermal energy and various new-energy coupling power generation methods. Through investigation and analysis, this review provides a complete understanding of various geothermal power generation technologies and provides insights into the future development direction.