Jerzy HICKIEWICZ, Piotr RATAJ, Przemysław SADŁOWSKI
Prof. dr inż. Włodzimierz Krukowski – the patron of the year 2017
Presented is the biography of Mr Włodzimierz Krukowski born in 1887 in the Polish city of Radom. He studied in Darmstadt and also graduated there – during his studies he was an outstanding student. Described are his research work achievements in Siemens electric energy meters laboratory in Norymberga (incl. 40 international patents). Discussed is also his remarkable activity at Politechnika Lwowska after 1930. Alas, this brilliant career was terminated in July 1941 by the Gestapo – he was executed, together with professors of four other Lwów universities, by a German firing squad at the site of Wzgórza Wuleckie in Lwów.
Keywords: Professor Włodzimierz Krukowski, biography, achievements
Ryszard BARTNIK, Adam JUSZCZAK
Mathematical models with continuous time economic and technical efficiency analysis of combined heat and electric energy generation sources, their market value and the analysis and valuation of a heat market provided by them
Presented is a unique methodology and mathematical models with continuous time technical and economical efficiency analysis of CHP sources and their market value as well as of analysis and valuation of a heat market provided by them. And, if it comes to the literature on the subject, there have been known and applied until now only the discrete records of the investment economic performance indicators which have a number of important drawbacks – but you cannot find such drawbacks in continuous time records. Presented here models are of general nature and when the heat production is substituted in them with a value of zero you get models destined for power stations or, when you zero the electric energy production, you get models that can be applied for heating stations.
Keywords: CHP sources, technical and economic efficiency analysis, mathematic models
Piotr BANASIAK, Anna GORCZYCA-GORAJ, Maksymilian PRZYGRODZKI
Analysis of load diagrams developed for selected segments of low voltage consumers
Presented are selected problems connected with developing of approximate electric energy consumption profile by finding relationships between individual groups of low voltage consumers. For this purpose averaged diagrams were used that had been prepared on the basis of available data. A thorough analysis was carried out of data from various segments of the low voltage consumption like drugstores, shops, eductional institutions, detached houses, petrol stations, apartments and others. The objective of the activities were attempts to distinct new groups of consumers and create some other kind of classification, different to the one functioning in the given population.
Keywords: electric energy consumption, consumption profiles, low voltage consumers
Błażej BZOWSKI, Aleksandra Teresa TRYCZ
Increase of PV silicon panels energy efficiency by changing panel inclination angle depending on time of the year
Technological innovations, designed to increase the amount of acquired solar energy, are beginning to play a more and more important role in the age of growing energy consumption and steadily decreasing amount of mineral resources. With the still high level of prices for energy storage and transmission, RES – including solar photovoltaics – make in most countries a constantly rising contribution to the total energy production. Despite various technical innovations, silicon cells still occupy a dominant position in the photovoltaic market. It also turned out that a simple way to increase the amount of energy obtained, especially in winter, is setting the panels at different angles depending on the season of the year and according to the maximum solar elevation angle. Such trivial idea, financed in large part by the Polish National Centre for Research and Development, enabled production of about 13% more energy in a year. The added value is snow self-removal in wintertime that reduces maintenance costs of installations.
Keywords: RES, photovoltaics, PV energy efficiency increase, energy saving, CO2 emission reduction
Buildings energy efficiency and urban heat islands
An urban heat island (UHI) is a meteorogical phenomenon consisting in occurrence of a higher air and neighbourhood temperature in urban agglomerations than in the surrounding them rural areas. Temperature differences occur during daytime and they can be mostly seen in late evenings, especially in winter seasons. It seems reasonable to take up many initiatives in towns to reduce the size of UHIs, guarantee bigger number of green areas in cities and promote such organization of space that will foster a sufficient air exchange with neighbouring areas. As a result, lowering of temperature in towns and reduction of pollution level will be possible.
Keywords: urban heat island (UHI), energy efficiency, heating, air conditioning
Reasonableness of material testing of 200 MW units boiler drums after elapse of design working life
The vast majority of the Polish 200 MW units have already completed their design working life i.e. 200 thousand hours. Results of the performed tests show on the examples of boiler drums the full picture of a material degradation level and give informations on such material properties like ductility and fracture toughness. They also prove that properties of a drum material can be very diverse. Determination of actual parameter values is invaluable in diagnostics of boiler drums working for over 200 thousand hours but it can be realised only by performing drum material destructive tests.
Keywords: 200 MW units, boiler drums, material testing
Artur JASIŃSKI, Michał KWIECIEŃ
Damages of measuring orifice plates mounted on high-pressure steam pipelines
As regards the elements of high-pressure steam pipelines of increased stiffness, especially the ones being in operation for a longer time than their design working life, it is necessary to systematically monitor their technical condition and therefore be able to early detect discontinuities or initial creep stages. Safe usage of materials characterized by lowered mechanical strength is possible but it enforces verification of operational conditions. Very important is the supervision element of pipelines assembly that is sometimes performed many years after their manufacture. During metallographic testing of high-pressure steam pipelines elements, a principle of local decohesion changes occurrence should be accepted that means necessity of performing the tests in many areas. Experience and proper qualifications of persons deciding on the testing range are also extremely important.
Keywords: high-pressure steam pipelines, technical inspection, measuring orifice plates