The introduction of this paper describes three thermoeletrical effects and their properties. It also deals with thermoelectrical cells, which are using Seebeck´s and Peltrier´s effects. The paper decribes principles how the Peltier´s cells work, their mathematical model, construction and practical use. The paper shows what kinds, shapes and output we can meet at the market and which kinds of parameters regulate their selection. The paper suggests the possibility to measure characteristic behaviour and quantity during laboratories tasks and their evaluations. At the conclusion is adduced the suggestion of laboratory task together with theoretically made pilot protocol.