7 research outputs found
Energy analysis of the cascade use of geothermal water in the greenhouse production at the Lunjkovec - Kutnjak field : master's thesis
Ulaskom u Europsku uniju, Republika Hrvatska preuzela je obvezu ispunjenja odreÄenih energetskih ciljeva izmeÄu kojih su i smanjenje stakleniÄkih plinova te poboljÅ”anje gospodarskih prilika koriÅ”tenjem obnovljivih izvora energije. Prva konkretna realizacija navedenih ciljeva je puÅ”tanje u rad prve geotermalne elektrane Velika Ciglena. Jedna od gospodarskih moguÄnosti koje se mogu poboljÅ”ati uz iskoriÅ”tavanje obnovljivih izvora energije je opskrba poljoprivrednih gospodarstava toplinskom energijom povoljne prodajne cijene buduÄi da se veliki udio BDP-a Hrvatske temelji na poljoprivredi. Na temelju karakteristika istražnog lokaliteta Lunjkovec ā Kutnjak i planiranog projekta izgradnje elektrane i proizvodnje i distribucije transformiranih oblika energije iz geotermalne energije izraÄen je dinamiÄki model iskoriÅ”tavanja geotermalne energije. Geotermalna energija bi se iskoriÅ”tavala za grijanje staklenika Äije su toplinske potrebe odreÄene na temelju vanjskih temperatura zraka u vremenskom periodu od 1999. do 2013. godine. Grijanje staklenika izvedeno je putem dva termotehniÄka rjeÅ”enja: sustava direktnog iskoriÅ”tavanja geotermalne energije koristeÄi ventilokonvektore i kaskadnog hibridnog sustava gdje se nakon direktnog iskoriÅ”tavanja geotermalne vode protok usmjerava na sljedeÄi sustav direktnog iskoriÅ”tavanja ventilokonvektorima ili na dizalice topline, ovisno o temperaturi geotermalne vode.By joining the European Union, the Republic of Croatia has undertaken the obligation to fulfill certain energy goals, which include reducing greenhouse gases and improving economic opportunities through the use of renewable energy sources. The first concrete realization of these goals is the commissioning of the first geothermal power plant at Velika Ciglena. One of the economic opportunities that can be improved with the use of renewable energy sources is the supply of farms and greenhouses with heat energy at a reasonable selling price, since a large share of Croatia's GDP is based on agriculture. Based on the characteristics of the Lunjkovec - Kutnjak geothermal field and the planned project for the construction of a geothermal power plant as well as the production and distribution of transformed forms of energy from geothermal energy, a dynamic model of utilization of geothermal energy from the waste heat of geothermal water was created. Geothermal energy could be used to heat greenhouses whose heat needs were determined based on outdoor air temperatures from 1999 to 2013. Greenhouse heating was performed through two thermo-technical solutions: a system of direct use of geothermal energy using a fan coil and a cascade hybrid system where, after the direct use of geothermal water, the flow is directed towards fan-coils or heat pumps, depending on the temperature of geothermal water
Energy analysis of the cascade use of geothermal water in the greenhouse production at the Lunjkovec - Kutnjak field : master's thesis
Ulaskom u Europsku uniju, Republika Hrvatska preuzela je obvezu ispunjenja odreÄenih energetskih ciljeva izmeÄu kojih su i smanjenje stakleniÄkih plinova te poboljÅ”anje gospodarskih prilika koriÅ”tenjem obnovljivih izvora energije. Prva konkretna realizacija navedenih ciljeva je puÅ”tanje u rad prve geotermalne elektrane Velika Ciglena. Jedna od gospodarskih moguÄnosti koje se mogu poboljÅ”ati uz iskoriÅ”tavanje obnovljivih izvora energije je opskrba poljoprivrednih gospodarstava toplinskom energijom povoljne prodajne cijene buduÄi da se veliki udio BDP-a Hrvatske temelji na poljoprivredi. Na temelju karakteristika istražnog lokaliteta Lunjkovec ā Kutnjak i planiranog projekta izgradnje elektrane i proizvodnje i distribucije transformiranih oblika energije iz geotermalne energije izraÄen je dinamiÄki model iskoriÅ”tavanja geotermalne energije. Geotermalna energija bi se iskoriÅ”tavala za grijanje staklenika Äije su toplinske potrebe odreÄene na temelju vanjskih temperatura zraka u vremenskom periodu od 1999. do 2013. godine. Grijanje staklenika izvedeno je putem dva termotehniÄka rjeÅ”enja: sustava direktnog iskoriÅ”tavanja geotermalne energije koristeÄi ventilokonvektore i kaskadnog hibridnog sustava gdje se nakon direktnog iskoriÅ”tavanja geotermalne vode protok usmjerava na sljedeÄi sustav direktnog iskoriÅ”tavanja ventilokonvektorima ili na dizalice topline, ovisno o temperaturi geotermalne vode.By joining the European Union, the Republic of Croatia has undertaken the obligation to fulfill certain energy goals, which include reducing greenhouse gases and improving economic opportunities through the use of renewable energy sources. The first concrete realization of these goals is the commissioning of the first geothermal power plant at Velika Ciglena. One of the economic opportunities that can be improved with the use of renewable energy sources is the supply of farms and greenhouses with heat energy at a reasonable selling price, since a large share of Croatia's GDP is based on agriculture. Based on the characteristics of the Lunjkovec - Kutnjak geothermal field and the planned project for the construction of a geothermal power plant as well as the production and distribution of transformed forms of energy from geothermal energy, a dynamic model of utilization of geothermal energy from the waste heat of geothermal water was created. Geothermal energy could be used to heat greenhouses whose heat needs were determined based on outdoor air temperatures from 1999 to 2013. Greenhouse heating was performed through two thermo-technical solutions: a system of direct use of geothermal energy using a fan coil and a cascade hybrid system where, after the direct use of geothermal water, the flow is directed towards fan-coils or heat pumps, depending on the temperature of geothermal water
Energy analysis of the cascade use of geothermal water in the greenhouse production at the Lunjkovec - Kutnjak field : master's thesis
Ulaskom u Europsku uniju, Republika Hrvatska preuzela je obvezu ispunjenja odreÄenih energetskih ciljeva izmeÄu kojih su i smanjenje stakleniÄkih plinova te poboljÅ”anje gospodarskih prilika koriÅ”tenjem obnovljivih izvora energije. Prva konkretna realizacija navedenih ciljeva je puÅ”tanje u rad prve geotermalne elektrane Velika Ciglena. Jedna od gospodarskih moguÄnosti koje se mogu poboljÅ”ati uz iskoriÅ”tavanje obnovljivih izvora energije je opskrba poljoprivrednih gospodarstava toplinskom energijom povoljne prodajne cijene buduÄi da se veliki udio BDP-a Hrvatske temelji na poljoprivredi. Na temelju karakteristika istražnog lokaliteta Lunjkovec ā Kutnjak i planiranog projekta izgradnje elektrane i proizvodnje i distribucije transformiranih oblika energije iz geotermalne energije izraÄen je dinamiÄki model iskoriÅ”tavanja geotermalne energije. Geotermalna energija bi se iskoriÅ”tavala za grijanje staklenika Äije su toplinske potrebe odreÄene na temelju vanjskih temperatura zraka u vremenskom periodu od 1999. do 2013. godine. Grijanje staklenika izvedeno je putem dva termotehniÄka rjeÅ”enja: sustava direktnog iskoriÅ”tavanja geotermalne energije koristeÄi ventilokonvektore i kaskadnog hibridnog sustava gdje se nakon direktnog iskoriÅ”tavanja geotermalne vode protok usmjerava na sljedeÄi sustav direktnog iskoriÅ”tavanja ventilokonvektorima ili na dizalice topline, ovisno o temperaturi geotermalne vode.By joining the European Union, the Republic of Croatia has undertaken the obligation to fulfill certain energy goals, which include reducing greenhouse gases and improving economic opportunities through the use of renewable energy sources. The first concrete realization of these goals is the commissioning of the first geothermal power plant at Velika Ciglena. One of the economic opportunities that can be improved with the use of renewable energy sources is the supply of farms and greenhouses with heat energy at a reasonable selling price, since a large share of Croatia's GDP is based on agriculture. Based on the characteristics of the Lunjkovec - Kutnjak geothermal field and the planned project for the construction of a geothermal power plant as well as the production and distribution of transformed forms of energy from geothermal energy, a dynamic model of utilization of geothermal energy from the waste heat of geothermal water was created. Geothermal energy could be used to heat greenhouses whose heat needs were determined based on outdoor air temperatures from 1999 to 2013. Greenhouse heating was performed through two thermo-technical solutions: a system of direct use of geothermal energy using a fan coil and a cascade hybrid system where, after the direct use of geothermal water, the flow is directed towards fan-coils or heat pumps, depending on the temperature of geothermal water
Two-Stage Geothermal Well Clustering for Oil-to-Water Conversion on Mature Oil Fields
There are numerous oil fields that are approaching the end of their lifetime and that have great geothermal potential considering temperature and water cut. On the other hand, the oil industry is facing challenges due to increasingly stringent environmental regulations. An example of this is the case of France where oil extraction will be forbidden starting from the year 2035. Therefore, some oil companies are considering switching from the oil business to investing in geothermal projects conducted on existing oil wells. The proposed methodology and developed conversions present the evaluation of existing geothermal potentials for each oil field in terms of water temperature and flow rate. An additional important aspect is also the spatial distribution of existing oil wells related to the specific oil field. This paper proposes a two-stage clustering approach for grouping similar wells in terms of their temperature properties. Once grouped on a temperature basis, these clusters should be clustered once more with respect to their spatial arrangement in order to optimize the location of production facilities. The outputs regarding production quantities and economic and environmental aspects will provide insight into the optimal scenario for oil-to-water conversion. The scenarios differ in terms of produced energy and technology used. A case study has been developed where the comparison of overall fields and clustered fields is shown, together with the formed scenarios that can further determine the possible conversion of petroleum assets to a geothermal assets
Investigation of Steady-State Heat Extraction Rates for Different Borehole Heat Exchanger Configurations from the Aspect of Implementation of New TurboCollectorā¢ Pipe System Design
When considering implementation of shallow geothermal energy as a renewable source for heating and cooling of buildings, special care should be taken in the hydraulic design of the borehole heat exchanger system. Laminar flow can occur in pipes due to the usage of glycol mixtures at low temperature or inadequate flow rates. This can lead to lower heat extraction and rejection rates of the exchanger because of higher thermal resistance. Furthermore, by increasing the flow rate to achieve turbulent flow and satisfactory heat transfer rate can lead to an increase in the pressure drop of the system and oversizing of the circulation pump which leads to impairment of the seasonal coefficient of performance at the heat pump. The most frequently used borehole heat exchanger system in Europe is a double-loop pipe system with a smooth inner wall. Lately, development is focused on the implementation of a different configuration as well as with ribbed inner walls which ensures turbulent flow in the system, even at lower flow rates. At a location in Zagreb, standard and extended thermal response tests were conducted on three different heat exchanger configurations in the same geological environment. With a standard TRT test, thermogeological properties of the ground and thermal resistance of the borehole were determined for each smooth or turbulator pipe configuration. On the other hand, extended Steady-State Thermal Response Step Test (TRST) incorporates a series of power steps to determine borehole extraction rates at the defined steady-state heat transfer conditions of 0/ā3 Ā°C. When comparing most common exchanger, 2U-loop D32 smooth pipe, with novel 1U-loop D45 ribbed pipe, an increase in heat extraction of 6.5% can be observed. Also, when the same comparison is made with novel 2U-loop D32 ribbed pipe, an increase of 18.7% is achieved. Overall results show that heat exchangers with ribbed inner pipe wall have advantages over classic double-loop smooth pipe designs, in terms of greater steady-state heat extraction rate and more favorable hydraulic conditions
Slagalica nasljeÄa : priruÄnik za opismenjavanje iz medicinske genetike
"Slagalica nasljeÄa" - priruÄnik za opismenjavanje iz medicinske genetike
ima tri namjene. Prije svega, on je edukativna slikovnica za studente,
lijeÄnike i pacijente, ali i druge zainteresirane pojedince jer su u njoj
kroz ilustracije objaÅ”njene osnove genetike Äovjeka, kao i osnove medicinske
genetike. Od toga kako prepoznati osobu s genetiÄkim poremeÄajem, kako
nastaju i koje vrste genetiÄkih poremeÄaja postoje pa sve do toga na koji ih
naÄin možemo dijagnosticirati. Nadalje, nakon svake ilustracije na pojedinoj
stranici nalaze se definicije 79 pojmova iz medicinske genetike koje Äine
tezaurus za studente, lijeÄnike i pacijente koji se na bilo koji naÄin
susreÄu s genetiÄkim poremeÄajima. Naposljetku, ova knjiga sadrži i primjere
reÄenica u koje su ubaÄeni struÄni pojmovi iz medicinske genetike, a koji su
namijenjeni studentima prilikom savladavanja komunikacijskih vjeŔtina na
kolegiju Medicinska genetika, ali i lijeÄnicima prilikom informiranja svojih
pacijenata o (moguÄem) genetiÄkom poremeÄaju.
Uz kreatoricu ideje i urednicu izdanja, doc. dr. sc. Ninu Perezu, autori
izdanja su studenti Ŕeste godine Integriranog preddiplomskog i diplomskog
sveuÄiliÅ”nog studija Medicina i prof. dr. sc. SaÅ”a OstojiÄ
Slagalica nasljeÄa : priruÄnik za opismenjavanje iz medicinske genetike
"Slagalica nasljeÄa" - priruÄnik za opismenjavanje iz medicinske genetike
ima tri namjene. Prije svega, on je edukativna slikovnica za studente,
lijeÄnike i pacijente, ali i druge zainteresirane pojedince jer su u njoj
kroz ilustracije objaÅ”njene osnove genetike Äovjeka, kao i osnove medicinske
genetike. Od toga kako prepoznati osobu s genetiÄkim poremeÄajem, kako
nastaju i koje vrste genetiÄkih poremeÄaja postoje pa sve do toga na koji ih
naÄin možemo dijagnosticirati. Nadalje, nakon svake ilustracije na pojedinoj
stranici nalaze se definicije 79 pojmova iz medicinske genetike koje Äine
tezaurus za studente, lijeÄnike i pacijente koji se na bilo koji naÄin
susreÄu s genetiÄkim poremeÄajima. Naposljetku, ova knjiga sadrži i primjere
reÄenica u koje su ubaÄeni struÄni pojmovi iz medicinske genetike, a koji su
namijenjeni studentima prilikom savladavanja komunikacijskih vjeŔtina na
kolegiju Medicinska genetika, ali i lijeÄnicima prilikom informiranja svojih
pacijenata o (moguÄem) genetiÄkom poremeÄaju.
Uz kreatoricu ideje i urednicu izdanja, doc. dr. sc. Ninu Perezu, autori
izdanja su studenti Ŕeste godine Integriranog preddiplomskog i diplomskog
sveuÄiliÅ”nog studija Medicina i prof. dr. sc. SaÅ”a OstojiÄ