Grzegorz BŁAJSZCZAK
Implementation of the European energy law
The European Union is currently processing preparation of a series of regulations concerning various aspects of network functioning and free market trading of electric energy and gas – the so-called “net codes”. Presented is here the process of constructing of the European energy law with a special attention paid to electric power generation. Discussed are also the EU organs and the more important institutions taking part in this process like the European Commission, ACER and ENTSO-E, as well as the member states’ organizations engaged in construction and implementation of this law.
Keywords: the European Union, energy law, European energy institutions
Janusz KOTOWICZ
Efficiency improvement potential of combined cycle gas turbines fired with natural gas
After an analysis of gas turbine combined cycle (GTCC) units efficiency had been made, the authors called an attention to the fact that the efficiency of a gas turbine is essential for the increase of a whole GTCC unit’s efficiency from both the economic and thermodynamic point of view. Commonly known is the influence of a turbine inlet temperature (TIT) on a GTCC efficiency so it is pointed out that the compression ratio, TIT and the compressor outlet temperature need to be considered together. In a GTCC unit’s efficiency analysis the crossing conditions of the subsequent efficiency barriers of 61%, 63 - 65% and 67% were indicated. Analysed was also the efficiency of GTCC units with CO2 sequestration. Shown is the influence of an oxygen production energy consumption on the efficiency of an oxy-combustion GTCC unit. Presented is a proposal of a gas turbine with a membrane reactor application in a zero-emission GTCC unit and determined is its efficiency.
Keywords: gas turbine combined cycle (GTCC) units, gas turbine efficiency
Bogdan RUSZCZAK, Michał TOMASZEWSKI
Supporting the overhead power lines operation process by reduction of winter weather conditions influence
Handling the winter unfavourable events by an operator must be based on integration of three main fields of activity: starting with multidimensional data analysis, then drawing conclusions and ending with taking up proper activities in the range of a crisis management. The basis of electrical distribution system hazard monitoring are measurements coming from transmission system operation registering devices and the condition of the infrastructure elements. These informations should be complemented with data coming from bases of other services functioning beyond a distribution or transmission network operator. Thus on the basis of informations coming from the hazard monitoring, the alerting system is able to work out multivariable prognostic models and scenarios of possible developments. The aim of its activity is estimation of a power network threat level by analyzing and verifying data characterizing an actual condition of a distribution network functioning and prognozing the possibility of hazard occurrence (early identification of a crisis situation). Beside the application of a computer support for each activity in frames of the crisis management it is on purpose to apply a computer system integrating the tools used in each particular phase. It is possible to create a new system supporting the operator with the aim to reduce the results of overhead line major failures caused by extreme weather conditions, or to equip the present functioning systems with new elements concerning the reduction of winter weather conditions influence on the work of a power network. The authors of this article are now working on the prototype of such system. Implementation of the proposed solution and its application for an adequately long time will enable gathering more informations about weather conditions having crucial influence on the power network operation process.
Keywords: overhead lines, operation processes, power line extreme working conditions
Andrzej FULCZYK
Adaptation of GTCC units to island operation on the example of EC Polkowice and some other power plants
Discussed is the method of a small gas fired unit adaptation to island operation and to the start-up with no power supply from external electrical network. Presented are main project assumptions, detection methods of generator island operation and comissioning test results. Adaptation of a small GTCC unit to an island operation is relatively simple. A small gas turbine can be started up with no need to have a big electric power supply source - a 1 MVA emergency generator is quite enough and such generators are more and more often met in power stations and industrial plants. Local islands can be created in this way and they would then enable the electric power supply to industrial plants needing a high level of energy security or provide electricity for starting up of other power units. In case of medium and big size units such adaptation meets considerably more difficulties connected mainly with technological problems.
Keywords: power unit island operation, GTCC units, unit adaptation to island operation
Jerzy KUBOWSKI
New nuclear power stations in Finland and Hungary
Discussed are reasons of making decision by Finnish and Hungarian authorities to build new nuclear plants based on a Russian design. Presented are also projects of these new power plants. The project of AES-2006 power plant shows new tendencies in an approach to the problem of nuclear plants safety and the most important representation of this is the elaboration of some original safety systems for AES-006 power plant which do not only, like in WWER-1000 reactor, take into consideration the control of maximum credible accident (MCA) but also of the beyond design-basis events. Low probability events belong to this group and they can be conditioned by either internal power plant problems or the external ones - not connected with construction defects nor with the so-called “human factor”. The basic safety criterion is not to allow the radioactive pollution to widespread beyond the boundary of power plant’s premises so in the AES-006 power plant design implemented are rigid standards of radiation protection. The values of radiation dose limits with reference to the staff and population are considerably reduced - they are even lower than the ones recommended by MAEA, e.g. the annual effective dose limit for the staff is 5 mSv/a that is four times lower than the one contained in MAEA recommendations, and the average annual effective dose during a plant’s operation - 2 µSv/a - is ten times lower. Also the effective individual population dose limit is only 10 mSv/a, that is ten times lower that the average annual dose limit - 100 mSv/a - according to MAEA standards.
Keywords: new Russian nuclear power plants, nuclear plant safety, radiation protection standards
Maciej DZIKUĆ, Stanisław URBAN
Assessment of thermal energy production impact on the environment in selected power plants
Presented is the LCA (Life Cycle Assessment) method to determine the impact of the energy production on the environment. Demonstrated is the usefulness of this method for the energy sector assessment. Presented is also the impact of the energy production in coal-fired power plants on the environment. Made is an analysis with the use of LCA method with the aim to compare the environmental impact of energy production in Polkowice and Legnica thermal-electric power stations. Pointed out is the difference in the obtained results and discussed are causes of the reported environmental impacts occurrence. Identified are measures that will help to reduce the energy production impact on the environment.
Keywords: Life Cycle Assessment, energy, ecology, hard coal, CHP stations
Monika GWOŹDZIK
Phosphorus segregation
Presented material concerns phosphorus segregation in low-alloy and cast steels being operated for a long time in high temperatures. In these low-alloy and cast steels (Cr-Mo, Cr-Mo-V) being used in conventional energy industry appliances for a long time and in temperatures in the range of 350-600oC the phosphorus is the most detrimental impurity that segregates to grain boundaries causing a decline of impact strength and the rise of the brittle transition temperature. The higher the content of phosphorus in steel and a cast steel, higher material strength and lower impact strength in initial state, the bigger is decline of impact strength during operation of equipment elements in high temperatures. Presented is, on the basis of literature and the author’s own research, the model of equilibrium and non-equilibrium phosphorus segregation as well as the desegregation of phosphorus on grain boundaries.
Keywords: low-alloy steels, steels for energy industry, phosphorus segregation