To increase the efficiency and reliability of a power plant by utilizing ICT, collaboration between the power plant operator and the plant manufacturer is indispensable. Mitsubishi Hitachi Power Systems, Ltd. (MHPS, our company) places an emphasis on providing a solution in which "we work together with the customer." This report introduces the cloud/edge service, system architecture, cyber security, data analysis technology and examples of service application of MHPS-TOMONI (thermal power generation digitalization service) that our company provides.