Developments of Geothermal – Biomass Hybrid GPP and IoT-AI System for GPP

Abstract

Japan has the world’s third largest reserves of geothermal resources (23GWe) after United States and Indonesia. Currently, almost 40 geothermal power plants, mainly located in Tohoku and Kyushu region, they are in operation with a total generation capacity of 546MWe. However, it is less than 5% of world’s total capacity of geothermal power plants. So now, the geothermal generation capacity in Japan is ranked just tenth, although used to be sixth in 2005. In 2011, the FIT scheme was adopted and regulations in national parks has been gradually relaxed by 2015. Then, in the past five years, new GPP (geothermal power plant) have already been built totaling over 20MWe. Now 35 big projects have been carried out in Japan and their total generation capacity is approximately 350MWe. Based on the government estimates, the generation capacity of GPPs in Japan can be almost tripled by 2030. So, now it is expected that the usage of geothermal energy in Japan will spread more rapidly in future years. In this paper, we introduce our two projects executed by CRIEPI since 2013 with government subsidy, (1) Hybrid GPP project and (2) Geothermal IoT-AI project. (1) Hybrid GPP project (FY2013-): We have developed highly efficient geothermal power plants to be hybridized with the other energy source, which is biomass, solar thermal energy, or exhaust heat from fuel cells, and so on. It is expected that the thermal efficiencies of these systems are improved by superheating the main steam through the use of the other energy sources. We have investigated the system feasibility of these hybrid power plants in the light of the engineering, economic performance, environmental laws and regulations. And now we have narrowed down the proposed site to install a new hybrid GPP for the first time in Japan. (2) Geothermal IoT-AI project (FY2018-): To make maintenance easy and lower maintenance cost, we have developed a surveillance IoT camera that can scan the numerical data from attached display on the power generator and a plant performance evaluation system using AI technology for small-scale binary power plant (less than 2,000kWe). In this paper, to report the latest status of this project, we discuss results of plant performance analysis of binary power plants. These two projects are supported by NEDO program, P13009 (FY2013 - FY2020). NEDO is a semi-governmental organization in Japan to promote the development and introduction of new energy technologies.