Goal of the contribution is to explain evaluation of economical environment that firms must respect during their business activity.External environment of mining firm includes except others technological development, economical situation, legislative by the wayof regulation, but in last time also stimulations from the government, competition behavior and other. Contribution is dealing also withenergetical effectiveness in the frame of economical evaluation applied in conditions of Slovak republic.The renewable energy sources are domestic sources of energy that help to enhance the safety of energy suppliesand the diversification of energy sources. The renewable energy is proved to be commercially viable for a growing list of consumersand uses. The renewable energy technologies provide many benefits that go well beyond the energy alone. More and more,the renewable energies contribute to the three pillars of the sustainable development in the economy, environment and the society.