In the global process of reducing greenhouse gases (GHG), independent power producer (IPP) sustainability is directly correlated with its emissions treatment. Carbon dioxide (CO2) is considered to be the main cause of additional greenhouse effect and has become one of the key factors in IPP's sustainability. Because the cost of electricity is included in every product or service, unexplored impact of greenhouse gas reduction process on IPP's performance can cause significant consequences on local and global levels, which are manifested in rising electricity prices, poor investment climate, uncompetitive industry and unnecessary environmental pollution. Different approaches for solving the problem are proposed, but emission obligations still are and will be the subject of intensive research. Also, there are significant differences and inconsistencies, which are manifested in methods, units and assumptions used for estimating carbon dioxide emission reduction costs. To fulfill emission obligations an IPP (located in the EU) can choose between purchasing emission unit allowances (EA) within the European Union Emission Trading Scheme (EU ETS) or installing a carbon capture and storage system CCS [19], [20]. The CCS is expected to play a significant role in slowing down climate change, and it is estimated that it could reduce overall emissions by 20 % until 2050 [21]. Also, it is important to note that the CCS is not a solution for a low-carbon production generation mix, but its role is to gain the time needed to develop new low-carbon power generation technologies. The first part of dissertation presents the research problem, scientific contributions and an overview of all chapters. The second part called "Global Greenhouse Gas Reduction Process" describes the greenhouse effect. The main greenhouse gases have been defined, among which carbon dioxide is the dominant one. The reasons for the process of reducing greenhouse gases have been elaborated. The historical development of the legislation regarding the process of reducing greenhouse gases is presented, and the market of emission allowances in Southeast Europe is described, which is specific to uneven treatment of emission obligations. The third part describes the impact of the GHG reduction process on the IPP, which results in its obligation to purchase emission allowances or to install a CCS system. Carbon capture efficiency is estimated in range from 85 % to 95 % [25]. This means that an IPP with a built-in CCS system located in the European Union is obliged to purchase emission permits, but only for 5 % to 15 % of the carbon dioxide produced. Also, the mechanism of emissions trading in the European Union is described. The main three parts of an IPP equipped with CCS are described: 1. carbon capture (which includes CO2 preparation for transport), 2. transport of carbon dioxide (pipelines or shipping) and 3. storage of carbon dioxide (on land or under the sea). Furthermore, sources and locations of possible carbon storage sites in Southeast Europe are presented. In the fourth part, an IPP model with built-in CCS is defined. This model is based on the energy consumption square curve coefficients (zero, first and second degree) for IPP on coal. Coal was chosen as the fuel, since coal is the "core" fuel of the world's energy, and the process of reducing greenhouse gases is most pronounced at power plants that use coal as their primary energy source. The independent electricity producer model deals with its technical, economical and environmental parameters. The fifth part describes improved mathematical method for assessing techno-economic features of GHG reduction technology on an IPP. Technical, economical and environmental factors of an IPP are clearly and unambiguously connected and regulated, which enables a more accurate evaluation. Also, the advantages of proposed mathematical method for assessing the impact of techno-economic features of greenhouse gas reduction technology are: - a clear correlation between the cost of emission obligations and the efficiency of the power plant, - a clear correlation between the cost of emission obligations and the operating point (operating power) of the power plant and - a clear correlation between the cost of emission obligations and the specifics of the IPP's fuel. In the sixth part, using nonlinear programming, the impact of GHG reduction technology on the case of an independent electricity producer with respect to the electricity market and the emission obligations market was investigated in the Southeast European Power System model that does not have an identical emission management pattern, which may directly affect its sustainability. Based on the analysis of simulation results and using an improved mathematical method, a correlation was determined between the cost of electricity production IPP depending on the choice of greenhouse gas reduction technology with respect to the characteristics of the electricity and emissions market. The proposed method allows more accurate determination of the impact of greenhouse gas reduction technology on the independent electricity producer with regard to electricity market factors and emission obligations. The advantage of the proposed method is a clear idea of the interaction of several technical, economical and environmental factors such as: - IPP utilization factor (depending on the way emission liabilities are treated), - selection of IPP operating point (active power) (which may be between the technical minimum and rated power), - type of IPP propellant (eg coal, gas, lignite, etc.), - quality of delivered fuel (eg coal with different heating power or carbon composition) - total investment costs, - load factor, - installed power of the plant, - economic life of the plant, - interest rate, - fixed maintenance costs, - insurance costs, - administration costs, - staff costs, - variable maintenance costs of the plant (ammonia, SO2, NOx, ash) - fuel price, - method of transport and storage of separated carbon dioxide and - price of emission permits. The seventh part presents the results of the assessment of the techno-economic characteristics of greenhouse gas reduction technology in the case of IPP, in order to analyze its competitiveness on the electricity market. In the eighth chapter, a review of obtained results is given, and possible instructions for further research are presented, given the impact of the greenhouse gas reduction process on the IPP. Annex A presents the impact of neighboring power systems on the power system of Southeast Europe. Estimated data are presented separately for each border electricity system on an hourly basis, taking into account different times of the year. Annex B presents the expected inflow to hydropower plants in Southeast Europe on a weekly basis. Finally, an independent electricity power producer model equipped with a carbon capture and storage system has been developed. The mathematical method for techno-economic characteristics impact assessing of greenhouse gas reduction technology for an independent electricity power producer (IPP) has been improved. For an IPP, connection between energy consumption curve, fuel characteristics and emission obligation costs is presented. Based on the collected and processed technical, economic and environmental Southeast Europe electrical power system factors, using nonlinear programming, simulations were developed in order to analyze and assess the impact of greenhouse gas reduction processes. Furthermore, based on the results obtained through the simulations, method for optimizing the choice of carbon dioxide emission reduction technology has been improved. It has been proven that the optimal way to fulfill emission obligations for an IPP enables better technical, economic and environmental results, which could have a positive effect on electricity prices, industry competitiveness and reduces unnecessary environmental pollution. The results of previous research do not offer a complete solution but represent a current view based on the present development of engineering knowledge, which is constantly supplemented by new technological improvements.