Nowadays heat pumps become very popular in the Latvian construction market. The most actual types are air to air and air to water heat pumps. The main reason is low initial investments. The overall season efficiency of heat pump is not widely addressed in existing researches. This paper aims to analyze already existing experience of heat pump application in cold climate. The most appropriate simulation tools were defined and simulation modules were developed. In addition, paper provides deep analysis of Latvian climate in order to get objective data on outdoor air and soil temperature fluctuation. Obtained results allow to reach European Regional Development Fund project “NEARLY ZERO ENERGY SOLUTIONS FOR UNCLASSIFIED BUILDINGS” Nr. 1.1.1.116A048 main targets and provides collection and analyses of information for development of optimal mobile energy source.