Analysis of the work of voltage group control systems in the Polish Power System
The presented in this article reflections show that the voltage group control systems have a very significant impact on the work of a power system. Ensuring proper voltage values in individual nodes of a system is one of the key elements of its safety. Growing power demand, restrictions in development of networks’ infrastructure and fluctuation of conditions, characteristic for the energy market development, make difficult the rational planning and running of a power system. So, in these conditions, grows also the role and importance of further development and proper operation of a hierarchic system controlling voltage levels and reactive power load flow in the PPS. Using the elaborated by the author computer simulation method and computing programs, one can easily analyse the influence of group control systems on the work of a power system. Simulation programs, used for the investigations, enble modeling of the work of group control systems in many generation and transmission nodes at the same time that in turn makes it possible to evaluate their interactions. Conducting of such investigations on real objects would be very expensive and time consuming and sometimes simply impossible. The elaborated method of simulation of group control systems’ work can also be used on the level of a power system operator. At the time being, preparations are made to implement into the PPS the system which enables conducting of the superior control of a voltage and a reactive power (SCADA/EMS system). One of the elements of this control system is determining of settings dedicated for group regulators on the basis of real data concerning the system’s actual work. The proposed and elaborated algorithms can be a very valuable complementary tool in the being created SCADA/EMS system.
Keywords: power system, voltage group control, computer simulation of control systems’ work
Krzysztof SIEKIERSKI, Maksymilian PRZYGRODZKI
The polygeneration system as one of the elements of a plant multicarrier media network
It is proved that, among the others, the building of a quattrogeneration system including a gas engine belongs to investments of an average rate of return equal 8 years that justifies its installing. Investing into construction of a polygeneration system with the high level of cogeneration, regardless the bigger investment cost connected with its building, is an undertaking significantly raising its energy efficiency that can in turn make it easier to obtain subsidies in the frames of the existing support systems for this kind of investments. Due to the fact that with the present legal regulations you do not need to obtain and then present for redemption by the ERO President of the certificates of origin for electricity produced in cogeneration, those certificates are not taken into account in the process of an investment efficiency calculation. But, if such solution should come again into force, the investment payback period would be significantly reduced. For the time being only the generation sources fed by biogas or a coke gas or a gas coming from degassing of mines can take into account, for the purpose of an investment efficiency settlement, the revenues achieved from the functioning renewable sources’ certificates and the so-called “violet” certificates. It is worth mentioning that, for the needs of the carried out analysis, the profits that can be generated by possible obtaining of energy efficiency certificates were not taken into account. The investment efficiency can be increased after receiving subsidies from a European fund in the frames of aid schemes. The building of a polygeneration system in a power utility increases the electric power supply safety for consumers sensitive to power interrruptions and intensifies elasticity of electric energy and heat economy management. So, in case of interruption in electric power supply from a distribution network belonging to a local operator, being in a possession of the polygeneration unit enables creation of an “island” allowing to feed appliances needing continuous power supply with the aim to ensure safety of the staff and the company property.
Keywords: utility power media networks, modernization of utility networks, polygeneration systems
Sławomir BIELECKI, Dominika JUSIŃSKA
Impact of the wind power engineering on the environment – people’s opinions
Wind power plants became a popular renewable energy source in Poland. Wind power engineering, like any technology, has its advantages and disadvantages, opponents and adherents, passionates and ignorants. The paper presents summary of people’s opinions and views concerning the influence of wind power plants on the environment and life comfort, elaborated on the basis of an especially conducted survey.
Keywords: renewable energy sources, wind power plants, public opinions
Global LNG trading
Discussed is the characteristics of a very dynamically changing world market for a liquified natural gas (LNG). In connection with the decrease in production of this blue fuel on the North Sea and abandonment of the South Stream project it will be necessary to find other ways to buy this raw material. It is worth mentioning now that the location of the being under construction gas terminal in Świnoujście will further enable the resale of this fuel to other countries of the Central Eastern Europe. The LNG port will then become an important place for gas deliveries in the north-south direction and the key plans of CEE GRIP development have already been presented by ENSTOG. In case of companies involved in LNG trading, a very important thing will be the development of the transmission infrastructure and building of interconnectors between Poland and the neighbouring countries.
Keywords: LNG world market, Polish gas terminal in Świnoujście, LNG trading
Marta DROSIŃSKA, Jerzy GŁUCH
Determination of operational characteristics of a turbine power unit with interstage reheat and a classical reactor in variable working conditions with the use of a numerical program for the parameters 28 MPa/550/580°C
Described are circulation investigations in varibale working conditions. The characteristics curves of the designed power output of 600 MW and 4 kPa pressure in a condenser in beyond design conditions were obtained by changing the pressure in a condenser and changes in the live steam mass. It was observed that there were achieved only small relative changes of a specific heat and power consumption. The occurrence of these changes was caused by variable working conditions of the condenser for the predetermined power unit load. Fluctuations in specific heat consumption are slightly bigger that is caused by the non-linear work of a steam turbine circulation and at the same time of the non-linear model of work while pressure fluctuations in the condenser are caused by the comparable with each other power changes for the same flow rate values.
Keywords: turbine power unit, interstage reheat, working conditions of a power unit
Joanna STASIAK-PANEK, Klaudia STANETA, Adam KUPCZYK, Karol TUCKI
The actual condition and development prospects of the transport biofuels sector in Poland
Characterized is the biocomponents production in Poland. Given are definitions concerning the transport biofuels sector contained in the EU and national legislation as well as legal regulations and new EU proposals referring to the biofuels market. Ascertained is that Poland has a big potential in the range of the transport biofuels production because of availability of edible and inedible raw materials but not a very big use is made of it as for now about 50% of biocomponents to be mixed with transport fuels comes from imports. The bioethanol market in Poland is still under development and modernization but the changing and complex national legal regulations adversely affect the transport biofuels sector growth and limit advancement of new technologies.
Keywords: transport biofuels, biofuels market in Poland, national and the EU biofuels legislation