Some Aspects of the Operation Work of Pump Station and Water Reservoir

This paper analyzes the impact of durations and starts of water pumping into the water reservoir on the capacity of the pumping station and water reservoir volume. Two different regimes of water consumption by the population are considered in combination with three different regimes of pumping station operation. The pumping station works in accordance with the usual regimes of the water pumping into the reservoir. The pumping is continuous, from 0 to 24 h, 22 to 6 h ("off-peak" period), and during the usual duration of solar radiation (from 6 to 18 h). A sensitivity analysis has been conducted, in the form of observing the effect of changes in duration and start of water pumping on the pumping station capacity and reservoir volume. The purpose of this research is to determine how the resulting functional dependencies can contribute to improving the operational characteristics of the pumping station and water reservoir. Also, this research provides new insights for the scientists and practical guidelines for the water supply system managers and engineers, allowing adjustment to the changes caused by the change of pumping station and water reservoir work regimes

EFFICIENT MONITORING OF VARIATION IN THE PARAMETERS OF DRINKING AND WASTEWATER QUALITY USING SPATIAL DATABASE AND APPLICATION OF RAPS

Currently, most communal utility management companies continually and automatically follow the changing trends in the drinking and wastewater quality (DWWQ) within their area of activity. Different control systems and applications are used for this purpose. Efficient monitoring of DWWQ should also include the analysis of water-quality parameters, such as the range of changes and trends. The method of Rescaled Adjusted Partial Sums (RAPS) is very suitable for the visualization and determination of the readily apparent features, which may be hidden from the common time-series plots of values. This paper presents different approaches for the tracking and analysis of the DWWQ parameters using a combination of the open-source spatial database, PostgreSQL, and the open-source GIS software. The proposed approach has not yet been used in the management of communal utilities. The main advantages of this modern system are the use of open-source programs and the high efficiency of water-quality monitoring with large datasets. However, the application of this system would require further training of employees in communal utility companies. The analysis results were all obtained for real locations

Characteristics of the concept of improving the operation work of the water supply system based on the use of solar photovoltaic energy

U radu se opisuje primjena solarne fotonaponske energije za opskrbu vodom urbanih vodnih sustava. Predloženi koncept temelji se na čistim i obnovljivim izvorima energije kao što je solarna energija. Rad sustava temelji se na solarnoj energiju koja je besplatna i široko dostupna. U ovom radu solarni fotonaponski sustavi su primijenjeni za proizvodnju ‘’zelene’’ električne energije. Zbog važnosti za održivost vodoopskrbe urbanog područja i zbog značajnih potrošača energije, čija cijena raste svaki dan, alternativno rješenje za energetske sustave traži se u obliku vodoopskrbnih sustava koji koriste solarne fotonaponske generatore. To je sustav čiji je rad definiran nizom čimbenika kao što su: klima, tlo, hidrološki podaci, potrebe za vodom itd. Taj sustav mora biti analiziran i optimiziran primjenom sustavnog pristupa. U ovom radu prezentirati će se osnovne karakteristike sustava koji se sastoji od solarnih fotonaponskih generatora, crpne stanice i vodospreme, te glavni hidraulički i energetski odnosi između tih elemenata. Metodologija za analizu i projektiranje sustava, kao i ekonomski čimbenici također će biti prikazani.This paper describes the application of a solar photovoltaic energy for urban water supply. Proposed concept is based on the clean and renewable energy sources, as it is solar energy. Operation of the system is based on solar energy which is free and widely available. In this paper, solar photovoltaic systems have been applied for green electric energy production. Due to the importance of water supply for urban area sustainability, and due to a significant energy consumer whose price is increasing each day, alternative solution to power systems are sought in the form of water supply systems which uses solar photovoltaic generator. It is a system, whose operation is defined by a range of factors such as: climate, soil, hydrological data, water demand etc. It has to be analyzed and optimized with the application of a systematic approach. In this paper, basic characteristics of the system consist of solar photovoltaic generator, pump station and water supply service reservoir and main hydraulic and energy relationship between his elements will be presented. The methodology for the system analysis and design as well as economical factors will be also presented

Sustainability of the Urban Water Supply System Operating : Doctoral Thesis

Opskrba vodom je od iznimnog značaja za održivost urbanih područja. Poznata je činjenica da se u tu svrhu koriste sve veće i veće količine energije iz fosilnih goriva, čija cijena se svakodnevno povećava. Kao alternativno rješenje nameće se korištenje Obnovljivih Izvora Energije (OIE), posebice Solarne Fotonaponske (PV) energije. Ova disertacija na inovativan i originalan način dokazuje održivost Urbanog Vodoopskrbnog Sustava (UVODS-u) uz primjenu PV energije. Koncept korištenja PV energije u UVODS-u u ovoj disertaciji zasniva se na Metodi Kritičnog Perioda (MKP). U sklopu MKP-a, definirani su kritični periodi i periodi bilanciranja. Njihovim uvođenjem i primjenom odnosno primjenom MKP-a postiže se pouzdanost dobivenog rješenja, pri čemu nastaje Energetski Održivi Urbani Vodoopskrbni Sustav (EOUVS). U ovoj disertaciji prikazane su hidrauličke i energetske značajke, te i metodologija dimenzioniranja EOUVS-a, koje će se prikazati na jednom hipotetskom primjeru, uzevši u obzir stvarne karakteristike analiziranog problema. Dobiveni rezultati su pokazali da je PV energija prikladna za primjenu u UVODS-u, odnosno za pogonsku (električnu) energiju crpnih stanica. Pri tome je dobiveno rješenje hidraulički i energetski održivo. U ovom rješenju vodosprema, uz uobičajenu ulogu spremnika vode, ima i ulogu spremnika energije. Prikazano rješenje ima pozitivan utjecaj na klimatske promjene, budući da značajno doprinosi smanjenju emisija stakleničkih plinova. Kod toga se klasična električna energija nastala korištenjem fosilnih goriva zamjenjuje ''Zelenom energijom'' iz PV sustava, pri čemu su količine emisija stakleničkih plinova koje se oslobađaju beznačajne. Predloženo rješenje ima i pozitivan društveni utjecaj na širu i užu zajednicu, budući da EOUVS pruža društvene koristi u svim svojim segmentima. Prikazano rješenje, kao i metodologija dimenzioniranja EOUVS-a su široko primjenjivi u skladu s karakteristikama vodoopskrbnog sustava i pripadnog klimatskog područja.Water supply is of great importance for the sustainability of urban areas. It is a known fact that increasing amounts of energy from fossil fuelsare used for this purpose, whose price is daily increasing. The use of Renewable Energy Sources (RES), in particular solar Photovoltaic (PV) energy is an alternative solutionto this problem. This thesis on innovative and original way proves the sustainability of Urban Water Supply System (UWSS), by using PV energy. Concept of using the PV energy in UWSS in this thesis is based on a method called Critical Period Method (CPM). Within CPM, critical periods and balancing periods were defined. By their introduction and application, respectively by use of the CPM, sustainability of the obtained solutionis achieved, to give the Energy Sustainable Urban Water Supply System (ESUWSS). In this thesis, hydraulically and energetically features, and also a sizing methodology of ESUWSS have been shown on a hypothetical example that has the characteristics of a real analyzed problem. The obtained results confirmed the hypothesis that PV energy is suitable for use in UWSS, i.e. for driving (electric) energy of pumping stations. The obtained solution is hydraulically and energetically sustainable. In the proposed solution, water reservoir (with the usual role of water storage) has the role of energy storage. The presented solution has a positive impact on the climate changes, since it significantly contributes to the reduction of greenhouse gas emissions. Herein, classical electric energy, produced by the use of fossil fuels, is entirely replaced with ''green'' energy from the PV system. Thereby, the amounts of greenhouse gases that are released are insignificant. The proposed solution has a positive social impact on wider and narrower community, since ESUWSS provides social benefits in all its aspects. The presented solution, as well as sizing methodology of ESUWSS, is widely applicable to various characteristics of a water supply system and climate

Sustainability of the Urban Water Supply System Operating : Doctoral Thesis

Opskrba vodom je od iznimnog značaja za održivost urbanih područja. Poznata je činjenica da se u tu svrhu koriste sve veće i veće količine energije iz fosilnih goriva, čija cijena se svakodnevno povećava. Kao alternativno rješenje nameće se korištenje Obnovljivih Izvora Energije (OIE), posebice Solarne Fotonaponske (PV) energije. Ova disertacija na inovativan i originalan način dokazuje održivost Urbanog Vodoopskrbnog Sustava (UVODS-u) uz primjenu PV energije. Koncept korištenja PV energije u UVODS-u u ovoj disertaciji zasniva se na Metodi Kritičnog Perioda (MKP). U sklopu MKP-a, definirani su kritični periodi i periodi bilanciranja. Njihovim uvođenjem i primjenom odnosno primjenom MKP-a postiže se pouzdanost dobivenog rješenja, pri čemu nastaje Energetski Održivi Urbani Vodoopskrbni Sustav (EOUVS). U ovoj disertaciji prikazane su hidrauličke i energetske značajke, te i metodologija dimenzioniranja EOUVS-a, koje će se prikazati na jednom hipotetskom primjeru, uzevši u obzir stvarne karakteristike analiziranog problema. Dobiveni rezultati su pokazali da je PV energija prikladna za primjenu u UVODS-u, odnosno za pogonsku (električnu) energiju crpnih stanica. Pri tome je dobiveno rješenje hidraulički i energetski održivo. U ovom rješenju vodosprema, uz uobičajenu ulogu spremnika vode, ima i ulogu spremnika energije. Prikazano rješenje ima pozitivan utjecaj na klimatske promjene, budući da značajno doprinosi smanjenju emisija stakleničkih plinova. Kod toga se klasična električna energija nastala korištenjem fosilnih goriva zamjenjuje ''Zelenom energijom'' iz PV sustava, pri čemu su količine emisija stakleničkih plinova koje se oslobađaju beznačajne. Predloženo rješenje ima i pozitivan društveni utjecaj na širu i užu zajednicu, budući da EOUVS pruža društvene koristi u svim svojim segmentima. Prikazano rješenje, kao i metodologija dimenzioniranja EOUVS-a su široko primjenjivi u skladu s karakteristikama vodoopskrbnog sustava i pripadnog klimatskog područja.Water supply is of great importance for the sustainability of urban areas. It is a known fact that increasing amounts of energy from fossil fuelsare used for this purpose, whose price is daily increasing. The use of Renewable Energy Sources (RES), in particular solar Photovoltaic (PV) energy is an alternative solutionto this problem. This thesis on innovative and original way proves the sustainability of Urban Water Supply System (UWSS), by using PV energy. Concept of using the PV energy in UWSS in this thesis is based on a method called Critical Period Method (CPM). Within CPM, critical periods and balancing periods were defined. By their introduction and application, respectively by use of the CPM, sustainability of the obtained solutionis achieved, to give the Energy Sustainable Urban Water Supply System (ESUWSS). In this thesis, hydraulically and energetically features, and also a sizing methodology of ESUWSS have been shown on a hypothetical example that has the characteristics of a real analyzed problem. The obtained results confirmed the hypothesis that PV energy is suitable for use in UWSS, i.e. for driving (electric) energy of pumping stations. The obtained solution is hydraulically and energetically sustainable. In the proposed solution, water reservoir (with the usual role of water storage) has the role of energy storage. The presented solution has a positive impact on the climate changes, since it significantly contributes to the reduction of greenhouse gas emissions. Herein, classical electric energy, produced by the use of fossil fuels, is entirely replaced with ''green'' energy from the PV system. Thereby, the amounts of greenhouse gases that are released are insignificant. The proposed solution has a positive social impact on wider and narrower community, since ESUWSS provides social benefits in all its aspects. The presented solution, as well as sizing methodology of ESUWSS, is widely applicable to various characteristics of a water supply system and climate

Pojednostavljeni postupak odabira optimalne varijante vodoopskrbnog sustava pokretanog solarnom fotonaponskom (FN) energijom

Rad prikazuje pojednostavljenu metodologiju odabira optimalne varijante vodoopskrbnog sustava, koji kao izvor energije koristi solarnu fotonaponsku (FN ili PV) energiju. Analizira se uobičajeni hibridni sustav koji se sastoji od solarnog fotonaponskog (FN ili PV) generatora i invertora, crpne stanice i vodospreme. Korištenjem Metode Kritičnog Perioda postiže se sustavna održivost takvog sustava. Pri tome se dobije pet, a po potrebi i više varijanti rješenja. Potrebno je uzeti u obzir činjenicu da je uz troškove, kao jednog od odlučujućih čimbenika, nužno razmotriti i ostale kriterije koji moraju biti zadovoljeni. To su u pravilu ekološki i socijalni kriteriji. Samim time, nameće se primjena višekriterijske metode, koja bi kod odabira i rangiranja dobivenih varijanti uzela u obzir sva tri navedena kriterija. Kao jedna od najprikladnijih višekriterijskih metoda odabrana je metoda PROMETHEE, koja će se primijeniti na primjeru vodoopskrbnog sustava naselja

SMART HYDRO-ENERGY HYBRID SYSTEM POTENTIAL IN CROATIA—BEDNJA RIVER CASE STUDY

The smart hydro-energy hybrid system comprises a small hydroelectric power plant and a solar photovoltaic power plant as a part of energy input for the realization of smart cities. This paper introduces the critical period method (CPM), which can be used for system sizing. According to this method, if the total energy production is lower than the energy demand, a critical period should be defined based on the largest difference between demand and production. The period (day) in which that difference appears is called the critical period. If the energy demand during this period is satisfied, the demand on the remaining days of the year is also satisfied. Any possible breaks in energy production, caused by a reduction in the expected river-flow rates or insolation (in the case of cloudiness), will be reduced to a minimum. The use of such a hybrid system guarantees the production of electricity throughout the year. Such a hybrid system could facilitate the realization of a smart city and help achieve energy stability and security. Despite Croatia having great potential in terms of solar energy use and the large number of available watercourses, such a hybrid system has never been realized. In particular, CPM has not been applied previously anywhere in the world

Implementation of multi-criterial analysis to selecting the optimal method for intrinsic vulnerability assessment of karst aquifers

Metode procjene prirodne ranjivosti temelje se na pretpostavci da prirodna fizička, kemijska i biološka obilježja vodonosnog sustava mogu pružiti određeni stupanj zaštite podzemne vode od onečišćenja. Problem primjene različitih metoda procjene ranjivosti na istom su području relativno velike razlike u konačnim rezultatima koje su posljedica određene subjektivnosti u procjenama kao i problem dostupnih podataka. Zbog toga se sve više pažnje posvećuje primjeni odgovarajućih metoda verifikacije rezultata procjene ranjivosti, a sve počinje od odabira optimalne metode. U ovom će radu biti će prikazani rezultati primjene četiriju metoda procjene ranjivosti (SINTACS, EPIK, PI i COP) na krškom vodonosniku u Hrvatskoj, slivu izvora Jadra i Žrnovnice. Zatim će biti predstavljen postupak primjene višekriterijske analize metodom PROMETHEE kojom su razmatrana različita obilježja pojedinih metoda. Na taj način se nastojala rangirati i izdvojiti najprihvatljivija metoda za primjenu na istraživanom području. Tako prikazani postupak mogao bi poslužiti kao standardna metoda odabira optimalne metode koja će biti primijenjena na području istraživanja, a sve sa svrhom verifikacije rezultata procjene prirodne ranjivosti u krškim vodonosnicima.Methods for natural vulnerability assessment are based on the assumption that natural physical, chemical and biological characteristics of an aquifer system can provide some level of groundwater protection from pollution. The problem of the implementation of different vulnerability assessment methods in one area is due to relatively large differences in their final results as a consequence of certain subjectivity in assessments as well as dana availability. For these reasons, increasingly more attention is paid to the implementation of appropriate methods to verify the results of vulnerability assessments, which all starts out with the selection of an optimal method. This paper will present the results of the implementation of four vulnerability assessment methods (SINTACS, EPIK, PI and COP) to a Croatian karst aquifer, the basin of the Jadro and Žrnovnica springs. This will be followed by the presentation of implementation of the multi-criterial analysis procedure by means of the PROMETHEE method which took into consideration different characteristic of individual methods. In this manner, the attempt was made to rank and select the most acceptable method for the implementation in the investigated area. Thus presented procedure could serve as a standard method for selecting the optimal method to be used in the investigated area with the purpose to verify the results of the natural vulnerability assessment of karst aquifers

The sensitivity analysis of input values in water supply system driven by solar photovoltaic energy

Obnovljivi izvori energije i njihova primjena danas su vrlo aktualni radi sve veće ekološke svijesti. U ovome radu govorit će se o solarnoj fotonaponskoj (FN) energiji korištenoj za crpljenje vode, odnosno o njenoj primjeni u navodnjavanju. Sustav koji je pokretan takvom energijom sastoji se od solarnog fotonaponskog generatora i invertora, crpne stanice, vodospreme i cjevovoda. Kako je solarna fotonaponska energija stohastičke naravi, ona ima utjecaj na sve dijelove promatranog sustava ovisno o klimatskim i tehnološkim faktorima. S obzirom na klimatske i tehnološkeparametre u ovome radu, napravljena je i analiza osjetljivosti pojedinih dijelova urbanog vodoopskrbnog sustava pokretanog solarnom fotonaponskom energijom. Time će se dobiti detaljniji uvid u značaj pojedinih ulaznih parametara na promjene njihovih vrijednosti, odnosno vidjet će se koji od tih faktora utječu najmanje a koji najviše, te koji od njih imaju proporcionalan i obrnuto proporcionalan utjecaj na urbani vodoopskrbni sustav pokretan FN energijom.Renewable energy sources and their usage are very actual nowadays, due to greater environmental awareness. This paper deals about the solar photovoltaic (PV) energy, which is used for waterpumping, orfor her using in irrigation. A system which is driven by such energy consists of solar photovoltaic generator and inverter, pumping stations, water tanks and pipelines. Because solar photovoltaic energy has stochastic nature, she also has an impact on all parts of the observed system depending on climatic and technological factors. Due to climatic and technologicalparameters, in this paper, an analysis of the sensitivity of certain parts of urban watersupply system driven by a photovoltaic energy has been made.This will give a more detailed insight into theimportance of individual input parameters due to change of their values, i.e. shows which of these factors affects at least or the most, or indicate which ofthem have proportional and inversely proportional impact to the urban water supply system driven by PV energy