A method of harnessing geothermal energy to produce electricity by lowering a geothermal generator deep into a pre-drilled well bore below the Earth's surface. The Self Contained In-Ground Geothermal Generator (SCI-GGG) includes a boiler, a turbine compartment, an electricity generator, a condenser and produces electricity down at the heat sources and transports it up to the ground surface by cable. The Self Contained Heat Exchanger (SCHE) is integral part of (SCI-GGG) system and can function independently. It consists of a closed loop system with two heat exchangers. No pollution is emitted during production process. There is no need for hydro-thermal reservoirs although not limited to hot rocks. It can be implemented in many different applications. The SCHE also includes an in-line water pump operatively coupled to the closed loop system and can be used in many different applications.