This paper presents aspects and problems of the Latvian energy-system connected to the choice of the CHP and/or power stations for the future national energy strategies. In the light of the last EU directive in the subjects of Renewable Energy Sources (RES) the share of electricity produced from RES at the moment is attested on the value of 42.4 % but should be increase to 49.3%. In the same time the share of renewable energy resources in the final energy consumption for 2020 should reach the level of 40% from 30%. Dependence on imported energy sources, growth of electricity prices, the need to support local producers are the main reasons for the use of new renewable energy technologies in the Latvian energy sector to implemented in refurbished energy supply system. Several methods fro the evaluation of the best strategy are explained. This apaper summarizes the application of the Energy Indicators for Sustainable Development (EISD) as good tool for analyzing trends, setting energy policy goals and monitoring progress. The results from the application of a multi-objective optimization regarding the implementation of the landfill biogas in the biogas treatement plant “Daibe” are reported.