This paper presents a simulation of the temperature distribution on the surface of a heat exchanger in the ANSYS application package. In the R&D part devoted to the development of a device for converting heat into electrical energy, models of an experimental heat exchanger have been created, including numerical models for calculating threedimensional distributions of the gas flow velocity, temperature fields, flow turbulence intensity and static pressure. An initial assessment of the parameters of the heat exchanger was carried out and the following predicted indicators were established at the flow rate and temperature of the inlet gases corresponding to data of the technical specifications. A combined analysis of the simulation results allows us to determine the zones for the most efficient installation of thermoelectric converters in electric energy: elements of the thermoelectric converter on the side surfaces of the cone. A prototype of the thermoelectric converter was developed and manufactured in the work, studies of thermoelectric conversion were conducted. The work also carried out the initial assessment of the state after the launch of prototypes of high-ampere electrolyzers of the RA-550 experimental section, namely, the measurement of the material balance of emissions through the housing lantern (outlet) and supply ventilation (inlet). All tasks of the stage have been fully resolved, the goals set and achieved, the results of the planned work received.