Petrogeothermal energy resources within low-temperature areas of Iceland

Iceland remains one of the leading countries in the field of the utilization of geothermal energy worldwide. Despite its knowledge and tremendous experience in the exploitation of mostly high-temperature geothermal energy resources (water and steam), it has been interested in the possibility of harnessing heat from hot rock formations with the implementation of the Enhanced Geothermal System (EGS). This paper presents the main outcomes of the feasibility study of EGS technology within the low-temperature area of the country. It includes broad geological research that constitutes the background for finding a suitable site for an EGS installation and to determine the local thermal parameters together with rock characteristics. To calculate the amount of heat stored within the preordained HDR formation and ascertain that the deployment of the EGS within the lowtemperature area of Hólmavík town (NW Iceland) is plausible, the term of static resources of energy was applied. Considering the geological issue, it emerged that within the low-temperature areas of Iceland, there are excellent lithological (mainly porous lava layers) as well as thermal conditions (relatively high heat flow and geothermal gradient values) for the implementation of EGS technology for providing heat for small district heating networks. The amount of energy stored within the designed rock formation turned out to be significant and more than sufficient to cover the energy demands of Hólmavík town. The authors also emphasize the importance of running several exchange programs between Polish and Icelandic research and academic centers, with the indication of possible benefits for the Polish geothermal energy sector

Study of wind power utilization in district heating systems in the Westfjords, Iceland

Some Renewable Energy Sources (RES), such as wind power, are often regarded as intermittent. That means they are not available on demand, but rather depend on external conditions e.g. such as the weather. In order to manage these resources, it is advised to combine them with energy storage or other energy sectors, what is known as “sector coupling”. This approach is set to mitigate the negative impact of unstable renewable energy sources and manage the generated surpluses. In this study, a system combining wind turbines, district heating network and short-term thermal energy storage was proposed and examined for the instance of the Westfjords, Iceland. Ísafjörður, Patreksfjörður, Bolungarvík and Flateyri are the exemplary communities with existing district heating networks, chosen to investigate the implementation of the system. A short review of the current state of the energy sector in Iceland was provided to present the local conditions. Wind potential in the described area was estimated as high in comparison with average wind turbine generation in the European Union and a few instances of wind turbines placement were analyzed in this study. For locations close to the district heating network, a long-term correlation between power generation and usage was proven. However, locating wind turbines in places with better wind conditions, provides stable output and a similar amount of energy produced by fewer generators

Modelling geothermal conditions in part of the Szczecin Trough – the Chociwel area

The Chociwel region is part of the Szczecin Trough and constitutes the northeastern segment of the extended Szczecin- Gorzów Synclinorium . Lower Jurassic reservoirs of high permeability of up to 1145 mD can discharge geothermal waters with a rate exceeding 250 m 3 /h and temperatures reach over 90°C in the lowermost part of the reservoirs. These conditions provide an opportunity to generate electricity from heat accumulated in geothermal waters using binary ORC (Organic Rankine Cycle) systems. A numerical model of the natural state and exploitation conditions was created for the Chociwel area with the use of TOUGH2 geothermal simulator (i.e., integral finite-difference method). An anal- ysis of geological and hydrogeothermal data indicates that the best conditions are found to the southeast of the town of Chociwel, where the bottom part of the reservoir reaches 3 km below ground . This would require drilling two new wells, namely one production and one injection. Simulated production with a flow rate of 275 m 3 /h, a temperature of 89°C at the wellhead, 30°C injection temperature and wells being 1.2 km separated from each other leads to a small temperature drop and moderate requirements for pumping power over a 50 years’ time span. The ORC binary system can produce at maximum 592.5 kW gross power with the R227ea found as the most suitable working fluid. Geothermal brine leaving the ORC system with a temperature c. 53°C can be used for other purposes, namely mushroom growing, balneology, swimming pools, soil warming, de-icing, fish farming and for heat pumps

Analyses of permeability and porosity of sedimentary rocks in terms of unconventional geothermal resource explorations in Poland

Petrophysical investigations are fundamental to natural resource exploration. In order to recognise the geothermal potential of sedimentary rocks in central Poland, 259 samples were collected from prospective deep-lying geothermal reservoirs. Parameters measured include bulk density, skeletal density, effective porosity, permeability, average pore diameter and specific surface. Results indicate that at great depths (mostly > 3,000 m below surface) sedimentary rocks show low values of porosity (mainly less than 5%) and permeability (only sporadically in excess of 1 md). These values call for a petrothermal use of reservoirs, for which an Enhanced Geothermal System (EGS) was developed. Reser- voirs suited for the EGS are Carboniferous and Lower Triassic sandstones in the central part of Poland (Mogilno-Łódź Trough region and a small part of the Kujawy Swell and Fore-Sudetic regions). In addition, Carboniferous limestones in this area are potentially prospective

Geothermal Systems—An Overview

This editorial aims to summarize 10 articles (7 scientific papers and 3 review papers) that contributed to the Special Issue “Geothermal Systems—An Overview”. This Special Issue contains information on both shallow and deep geothermal systems, and analyzes geothermal resources (low and high temperature) in various locations around the world

Analiza geologiczna i ocena zasobów wód i energii geotermalnej formacji mezozoicznej Niecki Szczecińskiej rozprawa doktorska /

Tyt. z ekranu tytułowego.Praca doktorska. Akademia Górniczo-Hutnicza im. Stanisława Staszica (Kraków), 2009.Zawiera bibliogr.Dostępna także w wersji drukowanej.Tryb dostępu: Internet.Model geologiczny mezozoiku Niecki Szczecińskiej, podział litostratygraficzny, rozpoznanie wiertnicze, tektonika plakantyklinalna, solna, litostratygrafia, kenozoik, kreda górna, dolna, jura górna, środkowa, dolna, trias górny, środkowy, dolny, podłoże mezozoiku, charakterystyka termiczna obszaru badań, wpływ występowania struktur solnych na rozkład parametrów termicznych w warstwach otaczających, strumień cieplny, temperatury wgłębne, charakterystyka hydrochemiczna, wpływ występowania struktur solnych na mineralizacje wód podziemnych zakumulowanych w warstwach otaczających, mineralizacja, typy wód, analiza potencjału geotermalnego zbiorników mezozoicznych, cech zbiornikowych, parametrów petrofizycznych zbiornika dolnojurajskiego, interpretacja wyników geofizyki wiertniczej, ogólna charakterystyka materiału, metodyka wykonanej interpretacji, charakterystyka hydrogeologiczna, model przepływu dolnojurajskich wód geotermalnych, podziemnych, analiza parametrów hydrogeologicznych, model koncepcyjny, numeryczny, weryfikacja modelu, bilans wodny, ocena zasobów energii geotermalnej, metodyka oceny zasobów, możliwości zagospodarowania, dotychczasowe wykorzystanie wód geotermalnych, ciepłownia geotermalno-gazowa w Pyrzycach, zakład geotermalny w Stargardzie Szczecińskim, uzdrowiska wykorzystujące wody geotermalne, perspektywy wykorzystania do celów ciepłowniczych, balneologicznych, rekreacyjnyc

Zasoby geotermalne warstw wodonośnych dolnej jury w niecce szczecińskiej Geothermal resources of Lower Jurassic aquifer in Szczecin Trough /

Tyt. z nagłówka.Bibliografia s. 221.Dostępny również w formie drukowanej.ABSTRACT: The paper presents results of estimation of geothermal energy resources accumulated in Lower Jurassic formation in Szczecin Trough. Calculations of resources were carried out in respective categories, in particular static geothermal energy resources, static recoverable geothermal resources and disposable geothermal reserves. Range and amounts of disposable geothermal energy resources determinate areas where geothermal plants could be constructed. KEYWORDS: geothermal resources, Lower Jurassic, Szczecin Trough. SŁOWA KLUCZOWE: zasoby geotermalne, jura dolna, niecka szczecińska

Prospects of Using Hydrocarbon Deposits from the Autochthonous Miocene Formation (Eastern Carpathian Foredeep, Poland) for Geothermal Purposes

There are many oil and gas fields around the world where the vast number of wells have been abandoned or suspended, mainly due to the depletion of reserves. Those abandoned oil and gas wells (AOGWs) are often located in areas with a prospective geothermal potential and might be retrofitted to a geothermal system without high-cost drilling. In Poland, there are thousands of wells, either operating, abandoned or negative, that might be used for different geothermal applications. Thus, the aim of this paper is not only to review geothermal and petroleum facts about the Eastern Carpathian Foredeep, but also to find out the areas, geological structures or just AOGWs, which are the most prospective in case of geothermal utilization. Due to the inseparability of geological settings with both oil and gas, as well as geothermal conditionings, firstly, the geological background of the analyzed region was performed, considering mainly the autochthonous Miocene formation. Then, geothermal and petroleum detailed characteristics were made. In the case of geothermal parameters, such as formation’s thickness, temperatures, water-bearing horizons, wells’ capacities, mineralization and others were extensively examined. Considering oil and gas settings, insights into reservoir rocks, hydrocarbon traps and migration paths issues were created. Then, for evaluating geothermal parameters for specific hydrocarbon reservoirs, their depths were established based on publicly available wells data. Thereafter, the average temperatures for selected reservoirs were set. As the effect, it turned out that most of the deposits have average temperatures of 40/50 °C, nonetheless, there are a few characterized by higher (even around 80 °C) temperatures at reasonable depths

Environmental aspects of the geothermal energy utilisation in Poland

Geothermal energy is considered as a strategic and sustainable source of renewable energy that can be effectively managed in several economic sectors. In Poland, despite the abundant potential of such resources, its share in the energy mix of renewable energy sources remains insubstantial. The utilisation of geothermal resources in Poland is related to the hydrogeothermal resources, however, numerous researches related to petrogeothermal energy resources are being performed. The utilisation of each type of energy, including geothermal, has an impact on the natural environment. In case of the effective development of geothermal energy resources, many environmental benefits are pointed out. The primary one is the extraction of clean, green energy that is characterised by the zero-emission rate of pollutants into the atmosphere, what considering the current environmental pollution in many Polish cities remains the extremely important issue. On the other hand, the utilisation of geothermal energy might influence the natural environment negatively. Beginning from the phase of drilling, which strongly interferes with the local landscape or acoustic climate, to the stage of energy exploitation. It should be noted that the efficient and sustainable use of geothermal energy resources is closely linked with the current law regulations at national and European level

Analyses of permeability and porosity of sedimentary rocks in terms of unconventional geothermal resource explorations in Poland

Petrophysical investigations are fundamental to natural resource exploration. In order to recognise the geothermal potential of sedimentary rocks in central Poland, 259 samples were collected from prospective deep-lying geothermal reservoirs. Parameters measured include bulk density, skeletal density, effective porosity, permeability, average pore diameter and specific surface. Results indicate that at great depths (mostly > 3,000 m below surface) sedimentary rocks show low values of porosity (mainly less than 5%) and permeability (only sporadically in excess of 1 md). These values call for a petrothermal use of reservoirs, for which an Enhanced Geothermal System (EGS) was developed. Reservoirs suited for the EGS are Carboniferous and Lower Triassic sandstones in the central part of Poland (Mogilno-Łódź Trough region and a small part of the Kujawy Swell and Fore-Sudetic regions). In addition, Carboniferous limestones in this area are potentially prospective