Danilo Feretić

Probabilistic analysis of electrical energy costs comparing: production costs for gas, coal and nuclear power plants

Abstract This paper considers the probabilistic analysis of lifetime discounted costs of electrical energy if produced in coal-fired, gas-fired and nuclear plants entering in operation in Croatia (similar as is in neighboring European countries) versus the end of this decade. The calculation considers all relevant costs in the period of loan repayment and after this period to the assumed end of plant life. The cost data are defined by best-estimated lower and upper cost limits with a probability distribution within these limits. An important factor for comparison of costs is related to assumed limits of rates of fuel cost changes for considered power technologies during plant operation time (during a period approximately from 2010 to 2040). These changes depend upon potential frictions in the fuel market in the considered period. The calculation is performed by using the Monte Carlo method (2000 calculations per technology) and STATS computer code. From the results of the simulations it can be concluded that the distribution of levelized bus bar costs for the combined cycle gas plant is in the range 4.5–8 US cents/kWh, with a most probable value of about 5.8 US cents/kWh; for coal-fired plants the corresponding values are 4.5–6.3 US cents/kWh and 5.2 US cents/kWh and for the nuclear power plant the corresponding values are in the range 4.2–5.8 US cents/kWh and a most probable value of about 4.8 US cents/kWh. In addition, the importance of considering the environmental impact of power plants and the application of corresponding external costs in the analyses of relative competitivity of power technologies is discussed.

Feasibility analysis of wind-energy utilization in Croatia

The competitiveness of wind powered generators built in Croatia has been investigated. Wind characteristics at suitable sites at 35-m height have been calculated by applying Weibull wind-distribution functions with altitude corrections suggested by Justus. Two sites on the Adriatic coast have been identified as promising locations and analyzed in detail, using a generally applicable method. Wind-power utilization at one of the sites with the best wind-energy potential in Croatia is now marginally competitive with fossil-fuel systems.

Potential advantages and disadvantages of sequentially building small nuclear units instead of a large nuclear plant

Abstract Renewal of nuclear power programs in countries with modest electricity consumptions and weak electrical grid interconnections has raised the question of optimal nuclear power plants sizes for such countries. The same question would be also valid for isolated or weakly connected regions within a large country. Building large size nuclear power plant could be prevented by technical or financial limits. Research programs have been initiated in the International Atomic Energy Agency and in the USA (within the framework of the Global Nuclear Energy Partnership (GNEP) program) with the aim to inspect under which circumstances small and medium reactors could be the preferred option compared to large nuclear plants. The economy of scale is a clear advantage of large plants. This paper compares, by using probabilistic methods, the net cash flow of large and medium size plants, taking as example a large nuclear plant (around 1200 MW) and four sequentially built smaller plants (300 MW). Potential advantages and disadvantageous of both options have been considered. Main advantages of the sequential construction of several identical small units could be the reduced investor risk and reduced investment costs due to the learning effect. This analysis is a part of studies for the Croatian power generating system development.

Analysis of future nuclear power plants competitive investment costs with stochastic methods

Abstract One of main issues in planning future power system expansion is forecast of expected electricity generating costs. Due to the fact that the forecast should be extended to plants lifetime it is best to consider and compare lifetime levelized cost of generated electricity for each of the candidate plants. The analysis is a part of studies for the future expansion of the Croatian power system, but is valid generally. The main competitors to nuclear power plants are combined cycle natural gas fired plants whose economy strongly depends upon gas cost. The expected increase of gas cost in following decades can substantially influence the competitiveness of nuclear plants versus gas fired plants. In addition, the costs of electricity produced by coal fired plants and wind electricity generators were also considered. Due to uncertainties of input parameters it is advantageous to use probabilistic instead of deterministic method of analysis. The paper considers the problem of the probabilistic distribution of nuclear power plant investment costs for which such plants could be competitive to gas fired plants for an estimated probable range of gas cost increase rates.

Analysis of power plants competitiveness using stochastic methods

The paper describes the application of a stochastic method for comparing economic parameters of future electrical power generating systems including conventional and nuclear power plants. The input data for calculation are cost elements defined in the frame of certain limits of expected occurrence with a probability distribution within the limits. The method is applied to establish competitive specific investment costs of future nuclear power plants when compared with combined cycle gas fired units combined with wind electricity generators using best estimated and optimistic input data.