scholarly journals Low-enthalpy Geothermal Energy Potential of Mine Water from Closured Underground Coal Mines in Northern Spain

2019 ◽  
Vol 103 ◽  
pp. 02007
Author(s):  
Javier Menéndez ◽  
Jorge Loredo

The contribution of renewable energies to the world's total energy demand has increased particularly during the last decades, and they will continue gaining market share. The European energy and climate policies have as one of their targets 20% of final energy from renewable origin by 2020. Underground coal mines closured and flooded constitute large underground reservoirs that can be economically managed to supply geothermal energy (heating and cooling) by means of heat pumps. This paper analyzes the geothermal potential of the water stored inside the coal mines of the Asturian Central Coal Basin (ACCB) and the reduction of CO2 emissions compared to the use of fossil fuels. The results of the study that has been carried out show a capacity of 50 MWt. The potential for generation thermal energy is 112,000 MWh/year with an electric consumption of 14,000 MWh/year. The Coefficient Of Performance (COP) medium is 8 kWht/kWhe. The reduction of CO2 emissions compared to other fuel sources can reach 80%.

2020 ◽  
Author(s):  
Kaan Yamanturk ◽  
Cihan Dogruoz

As it is known, the utilization and production of renewable energy resources are very important in recent years. Due to its geological structural formations, Turkey has a serious geothermal energy potential as a renewable energy resource comparing with the other countries. West side of Turkey has also a critical role to use the geothermal energy resources. In these fields, geothermal is mostly used in electricity generation, greenhouse heating and locational requirements. The components while producing the geothermal water from wells such as heating pumps, re-injection pipes and other equipment are also significant. In this study, coefficient of performance (COP) utilizing in heat pumps has been investigated and the new approach to find out the parameter has been identified. Based on COP equation, the formula of COP has been re-coded on Dev C++ compiler by using C++ computer language in order to focus on the importance of computer aided applications in geothermal energy sector. There are no more studies showing the COP with C++ codes in literature. On the other hand, Germencik region, in the west side of Turkey, has been evaluated and the production processes by Guris Construction and Engineering Co. Inc. have been explained in the study. Moreover, the potential of Turkey has also been mentioned in this study. The aim of the study is to examine the Germencik region geothermal energy potential and to improve the coefficient of performance by using C++ in heat pumps. The result of this study shows us the Germencik region has an important potential and the computer aided technologies can also be adapted easily into the processes while producing geothermal energy.


2021 ◽  
Vol 11 (6) ◽  
pp. 2691
Author(s):  
Nataša Ćuković Ignjatović ◽  
Ana Vranješ ◽  
Dušan Ignjatović ◽  
Dejan Milenić ◽  
Olivera Krunić

The study presented in this paper assessed the multidisciplinary approach of geothermal potential in the area of the most southeastern part of the Pannonian basin, focused on resources utilization. This study aims to present a method for the cascade use of geothermal energy as a source of thermal energy for space heating and cooling and as a resource for balneological purposes. Two particular sites were selected—one in a natural environment; the other within a small settlement. Geothermal resources come from different types of reservoirs having different temperatures and chemical compositions. At the first site, a geothermal spring with a temperature of 20.5 °C is considered for heat pump utilization, while at the second site, a geothermal well with a temperature of 54 °C is suitable for direct use. The calculated thermal power, which can be obtained from geothermal energy is in the range of 300 to 950 kW. The development concept was proposed with an architectural design to enable sustainable energy efficient development of wellness and spa/medical facilities that can be supported by local authorities. The resulting energy heating needs for different scenarios were 16–105 kW, which can be met in full by the use of geothermal energy.


Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2347
Author(s):  
Elżbieta Hałaj ◽  
Jarosław Kotyza ◽  
Marek Hajto ◽  
Grzegorz Pełka ◽  
Wojciech Luboń ◽  
...  

Krakow has an extensive district heating network, which is approximately 900 km long. It is the second largest city in terms of the number of inhabitants in Poland, resulting in a high demand for energy—for both heating and cooling. The district heating of the city is based on coal. The paper presents the conception of using the available renewable sources to integrate them into the city’s heating system, increasing the flexibility of the system and its decentralization. An innovative solution of the use of hybrid, modular heat pumps with power dependent on the needs of customers in a given location and combining them with geothermal waters and photovoltaics is presented. The potential of deep geothermal waters is based on two reservoirs built of carbonate rocks, namely Devonian and Upper Jurassic, which mainly consist of dolomite and limestone. The theoretical potential of water intake equal to the nominal heating capacity of a geothermal installation is estimated at 3.3 and 2.0 MW, respectively. Shallow geothermal energy potential varies within the city, reflecting the complex geological structure of the city. Apart from typical borehole heat exchangers (BHEs), the shallower water levels may represent a significant potential source for both heating and cooling by means of water heat pumps. For the heating network, it has been proposed to use modular heat pumps with hybrid sources, which will allow for the flexible development of the network in places previously unavailable or unprofitable. In the case of balancing production and demand, a photovoltaic installation can be an effective and sufficient source of electricity that will cover the annual electricity demand generated by the heat pump installation, when it is used for both heating and cooling. The alternating demand of facilities for heating and cooling energy, caused by changes in the seasons, suggests potential for using seasonal cold and heat storage.


Author(s):  
Leon M. Headings ◽  
Gregory N. Washington

The goal of this research is to develop a framework for replacing conventional heating and cooling systems with distributed, continuously and electrically controlled, building-integrated thermoelectric (BITE) heat pumps. The coefficient of performance of thermoelectric heat pumps increases as the temperature difference across them decreases and as the amplitude of temperature oscillations decreases. As a result, this research examines how thermal insulation and mass elements can be integrated with thermoelectrics as part of active multi-layer structures in order to minimize net energy consumption. In order to develop BITE systems, an explicit finite volume model was developed to model the dynamic thermal response of active multi-layer wall structures subjected to arbitrary boundary conditions (interior and exterior temperatures and interior heat loads) and control algorithms. Using this numerical model, the effects of wall construction on net system performance were examined. These simulation results provide direction for the ongoing development of BITE systems.


Author(s):  
Xinli Lu ◽  
David R. Larson ◽  
Thomas R. Holm

Groundwater source heat pumps exploit the difference between the ground surface temperature and the nearly constant temperature of shallow groundwater. This project characterizes two areas for geothermal heating and cooling potential, Mason County in central Illinois and the American Bottoms area in southwestern Illinois. Both areas are underlain by thick sand and gravel aquifers and groundwater is readily available. Weather data, including monthly high and low temperatures and heating and cooling degree days, were compiled for both study areas. The heating and cooling requirements for a single-family house were estimated using two independent models that use weather data as input. The groundwater flow rates needed to meet these heating and cooling requirements were calculated using typical heat pump coefficient of performance values. The groundwater in both study areas has fairly high hardness and iron concentrations and is close to saturation with calcium and iron carbonates. Using the groundwater for cooling may induce the deposition of scale containing one or both of these minerals.


Author(s):  
Mohammad Omar Temori ◽  
František Vranay

In this work, a mini review of heat pumps is presented. The work is intended to introduce a technology that can be used to income energy from the natural environment and thus reduce electricity consumption for heating and cooling. A heat pump is a mechanical device that transfers heat from one environmental compartment to another, typically against a temperature gradient (i.e. from cool to hot). In order to do this, an energy input is required: this may be mechanical, electrical or thermal energy. In most modern heat pumps, electrical energy powers a compressor, which drives a compression - expansion cycle of refrigerant fluid between two heat exchanges: a cold evaporator and a warm condenser. The efficiency or coefficient of performance (COP), of a heat pump is defined as the thermal output divided by the primary energy (electricity) input. The COP decreases as the temperature difference between the cool heat source and the warm heat sink increases. An efficient ground source heat pump (GSHP) may achieve a COP of around 4. Heat pumps are ideal for exploiting low-temperature environmental heat sources: the air, surface waters or the ground. They can deliver significant environmental (CO2) and cost savings.


Author(s):  
Praveen Cheekatamarla ◽  
Vishaldeep Sharma ◽  
Bo Shen

Abstract Economic and population growth is leading to increased energy demand across all sectors – buildings, transportation, and industry. Adoption of new energy consumers such as electric vehicles could further increase this growth. Sensible utilization of clean renewable energy resources is necessary to sustain this growth. Thermal needs in a building pose a significant challenge to the energy infrastructure. Supporting the current and future building thermal energy needs to offset the total electric demand while lowering the carbon footprint and enhancing the grid flexibility is presented in this study. Performance assessment of heat pumps, renewable energy, non-fossil fuel-based cogeneration systems, and their hybrid configurations was conducted. The impact of design configuration, coefficient of performance (COP), electric grid's primary energy efficiency on the key attributes of total carbon footprint, life cycle costs, operational energy savings, and site-specific primary energy efficiency are analyzed and discussed in detail.


Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2496 ◽  
Author(s):  
Laura Carnieletto ◽  
Borja Badenes ◽  
Marco Belliardi ◽  
Adriana Bernardi ◽  
Samantha Graci ◽  
...  

The design of ground source heat pumps is a fundamental step to ensure the high energy efficiency of heat pump systems throughout their operating years. To enhance the diffusion of ground source heat pump systems, two different tools are developed in the H2020 research project named, “Cheap GSHPs”: A design tool and a decision support system. In both cases, the energy demand of the buildings may not be calculated by the user. The main input data, to evaluate the size of the borehole heat exchangers, is the building energy demand. This paper presents a methodology to correlate energy demand, building typologies, and climatic conditions for different types of residential buildings. Rather than envelope properties, three insulation levels have been considered in different climatic conditions to set up a database of energy profiles. Analyzing European climatic test reference years, 23 locations have been considered. For each location, the overall energy and the mean hourly monthly energy profiles for heating and cooling have been calculated. Pre-calculated profiles are needed to size generation systems and, in particular, ground source heat pumps. For this reason, correlations based on the degree days for heating and cooling demand have been found in order to generalize the results for different buildings. These correlations depend on the Köppen–Geiger climate scale.


2020 ◽  
Vol 180 ◽  
pp. 02005
Author(s):  
Madalina Ghilvacs ◽  
Razvan Carlanescu ◽  
Maria Paraschiv ◽  
Malina Prisecaru

In a world where the energy demand is increasing daily, energy efficiency and renewable energy play a major role. Our research comes to help fighting the biggest problem that our world is facing today, global warming. This study aims to evaluate the energy potential of biofuels obtained from camelina sativa in order to reduce fossil fuel dependence, greenhouse gas emissions and increase energy efficiency. Camelina (Camelina sativa L.) is a cruciferous oilseed plant belonging to the Brassicaceae (mustard) family with the common name false flax and gold of pleasure. Since camelina can grow under different conditions without being a competitor of food land, this energetic plant can be used for production of both, firstand second-generation biofuels. In our study we determined the elemental analysis of the subproducts obtained from camelina sativa, through experimental tests, and we built a mathematical model to determine the calorific power and to simulate the burning of the biofuels into a steam generator in order to analyse the energy potential. The results show us that the biofuels obtained from camelina sativa can represent an alternative to fossil fuels and should be considered in the transition to green energy.


Sign in / Sign up

Export Citation Format

Share Document