A complex study on the possibilities to achieve the targets of low carbon society in the energy sector is presented through the framework of scaling-up methodology. The novelty of the research lays in the application of various methodologies for various levels of the governance in order to achieve one common target a low carbon society. To the author’s knowledge, it is for the first time when the scaling-up framework has been presented for all levels of energy systems, starting from a single energy production unit up to the state energy sector. The novelty of this methodology is in its application to study four individual domains: the combined heat and power production unit, district heating network, municipal energy plan and low carbon strategy. The Thesis presents various methodologies suitable for use in these defined domains, thus outlining the presented scaling-up framework. The framework of scaling-up demonstrates 14 distinct methodologies applied to the energy sector. Firstly, the scaling-up methodology itself is presented and discussed. Secondly, each domain of research is outlined by the remaining methodologies: where 1) the domain of combined heat and power production unit is studied using the energy, exergy, emergy, regression and correlation analysis; 2) the domain of district heating network is studied using the multiple-criteria decision analysis and modelled for future development scenarios; 3) the domain of municipal energy plans is studied using a time series forecasting tool and a climate change indicator; and 4) the domain of low carbon strategy is studied using the archetype “Distraction” and the algorithms are developed to reach a low carbon strategy. The methodologies are validated in various case studies in Latvia and are presented in the Thesis.