The economy activity in Serbia is burdened by lots of unfavourable circumstances, including the natural catastrophe so far unseen on this area in May 2014. The unemployment is long-term problem not being resolved with the 'employment policies' but with promotion of investments and achieving the economic growth and development. However, all sectors cannot become the pillars of increase of number and creation of new workplaces. The creators of local economic projections and programmes most frequently use the word 'restructuring'. But in practice, the 'restructuring' demands much more complex and more serious approach so far, above all to public sector of economy. The Serbian energy sector, and above all its public sector, is in front of great challenges deriving from urgent needs of current rehabilitation of flood after effects, from new strategic demands, as well as from European standard. The energy sector is by tradition important determinant of growth and stability of the entire economy. In Serbia, that is especially important considering the state of the capacities and legacy from the past. Modernisation of energy sector implies the application of many new dimensions of sustainability which need to be achieved. Unused renewable sources represent the opportunity for the increase of green investments, sustainable employment, and 'green jobs' in this sector. 'Green economy' and sustainable energy sector represent great opportunity for the future of Serbia. Stabilization and ecologisation of the capacities for the production of thermoelectric energy, increase of the share of renewable sources, and above all the measures of energy efficiency will represent crucial steps and measures towards sustainable energy sector in Serbia. Perhaps they represent true challenge for new construction works, new infrastructure, rehabilitation of schools and hospitals, modernisation of agriculture and tourism, as well as new public and private sector manufacturing capacities.