EFFICIENCY ANALYSIS FACTOR DETERMINATION STUDY FOR ÇİTGÖL MUNICIPALITY REGIONAL HEATING SYSTEM PROJECT WITH GEOTHERMAL ENERGY

In recent years, with the continuous urban expansion, the central heating sources are commonly insufficient in the areas of Northern China. Besides, the increasing heat transfer temperature difference results in more and more exergy loss between the primary heat network and the secondary heat network. This paper introduces a new central heating system which combines the urban heat network with geothermal energy (CHSCHNGE). In this system, the absorption heat exchange unit, which is composed of an absorption heat pump and a water to water heat exchanger, is as alternative to the conventional water to water heat exchanger at the heat exchange station, and the doing work ability of the primary heat network is utilized to drive the absorption heat pump to extract the shallow geothermal energy. In this way, the heat supply ability of the system will be increased with fewer additional energy consumptions. Since the water after driving the absorption heat pump has high temperature, it can continue to heat the supply water coming from the absorption heat pump. As a result, the water of the primary heat network will be stepped cooled and the exergy loss will be reduced. In this study, the performance of the system is simulated based on the mathematical models of the heat source, the absorption heat exchange unit, the ground heat exchanger and the room. The thermodynamic analyses are performed for three systems and the energy efficiency and exergy efficiency are compared. The results show that (a) the COP of the absorption heat exchange unit is 1.25 and the heating capacity of the system increases by 25%, which can effectively reduce the requirements of central heating sources; (b) the PER of the system increases 14.4% more than that of the conventional co-generation central heating system and 54.1% more than that of the ground source heat pump system; (c) the exergy efficiency of the CHSCHNGE is 17.6% higher than that of the conventional co-generation central heating system and 45.6% higher than that of the ground source heat pump system.

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Shallow geothermal energy integration in district heating system: An example from Serbia

Renewable Energy ◽

10.1016/j.renene.2018.11.103 ◽

2020 ◽

Vol 147 ◽

pp. 2791-2800 ◽

Cited By ~ 4

Author(s):

Miroslav V. Kljajić ◽

Aleksandar S. Anđelković ◽

Vaclav Hasik ◽

Vladimir M. Munćan ◽

Melissa Bilec

Keyword(s):

Geothermal Energy ◽

District Heating ◽

Heating System ◽

Energy Integration ◽

District Heating System ◽

Shallow Geothermal Energy

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Numerical evaluation of building heating potential from a co-axial closed-loop geothermal system using wellbore–reservoir coupling numerical model

Energy Exploration & Exploitation ◽

10.1177/0144598719889799 ◽

2019 ◽

Vol 38 (3) ◽

pp. 733-754 ◽

Cited By ~ 1

Author(s):

Tianfu Xu ◽

Zixu Hu ◽

Bo Feng ◽

Guanhong Feng ◽

Fengyu Li ◽

...

Keyword(s):

Geothermal Energy ◽

Closed Loop ◽

Heating System ◽

Coupling Model ◽

Production Performance ◽

Heat Extraction ◽

Geothermal System ◽

Renewable Energy Resources ◽

Practical Engineering ◽

System Maintenance

Geothermal energy is one of the most potential renewable energy resources. How to efficiently extract and utilize geothermal energy has been a worldwide hot topic. Co-axial closed-loop geothermal system is a novel method using a continuously closed wellbore without water exchange with. It is more suitable for reservoirs with medium or low temperature and permeability because many problems could be avoided such as lack of in situ groundwater or low infectivity of the reservoir. Many companies and research institutes have applied closed-loop geothermal system in building heating engineering and some fine results have been gained. However, in practical engineering construction, the area of a closed-loop geothermal system heating system is a very important parameter. It directly determines the cost accounting and initial design of the project. Accurate and reliable estimation of heating capacity becomes very important. In this study, a wellbore–reservoir coupling model is established, which is calibrated using measured data from a short-term field trial operation. We have carried out mixed convective–conductive fluid-flow modeling using a wellbore flow model for TOUGH2 called T2Well to investigate the heat extraction performance of closed-loop geothermal system. The system evolution and the effect of flow rate and injection temperature on heat production performance are discussed. The result shows that the intermittent production cycles are more beneficial for heat extraction and system maintenance, and the temperature recovery between two heating seasons is enough to maintain system heating. And we can calculate that a geothermal well can ensure heating of buildings of 10,000–20,000 m2 and the heating area of intermittent operation is 4000 m2 more than continuous operation. Besides, the sensitivity analysis of parameters is also carried out.

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Advanced exergo-environmental analyses and assessments of a real district heating system with geothermal energy

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2016.11.054 ◽

2017 ◽

Vol 113 ◽

pp. 449-459 ◽

Cited By ~ 10

Author(s):

Muhammet Yürüsoy ◽

Ali Keçebaş

Keyword(s):

Geothermal Energy ◽

District Heating ◽

Heating System ◽

District Heating System

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Utilization of geothermal springs as a renewable energy source: Vranjska Banja case study

Thermal Science ◽

10.2298/tsci190816391d ◽

2019 ◽

Vol 23 (6 Part B) ◽

pp. 4083-4093

Author(s):

Stefan Denda ◽

Jasna Micic ◽

Ana Milanovic-Pesic ◽

Jovana Brankov ◽

Zeljko Bjeljac

Keyword(s):

Geothermal Energy ◽

District Heating ◽

Field Research ◽

Economic Assessment ◽

Heating System ◽

Energy Utilization ◽

Geothermal Resources ◽

Geothermal Heating ◽

Public Facilities ◽

Total Energy Balance

Despite the significant natural potential, geothermal energy in Serbia has traditionally been used in balneology and recreation, while its share in the country?s total energy balance is almost negligible (0.05%). The present paper deals with the City Municipality of Vranjska Banja as a pioneer in the territory of Serbia in using geothermal energy for heating. The concept and methodology of the present research are directly related to the utilization of geothermal resources for district heating in the Vranjska Banja area. The presented analysis includes: determining the available amount of energy, identifying the energy needs of selected public facilities, and the estimation of investment necessary for energy utilization. A survey, combined with field research, is focused on four public facilities connected to the heating system relying on geothermal sources, as well as on two facilities that should be connected to the system in the next phases. The results show economic, ecological, and technological advantages of using geothermal heating systems, as well as the acceptable price of equipment maintenance. An economic assessment of the transition of one facility from the existing heating system to a system relying on geothermal energy has also been made. The analysis confirms the cost-effectiveness of using geothermal energy and reveals numerous ecological advantages (safe heating, absence of CO2 emission) over other energy sources.

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Dynamic modeling of а heating system using geothermal energy and storage tank

Thermal Science ◽

10.2298/tsci120222138m ◽

2012 ◽

Vol 16 (3) ◽

pp. 947-953

Author(s):

Predrag Milanovic ◽

Olivera Ecim ◽

Milos Jelic ◽

Vojislav Tomic

Keyword(s):

Energy Efficiency ◽

Dynamic Modeling ◽

Geothermal Energy ◽

Storage Tank ◽

Heating System ◽

Energy Requirements ◽

Air Temperatures ◽

Insufficient Amount ◽

Tank Capacity ◽

And Storage

This paper analyzes a greenhouse heating system using geothermal energy and storage tank and the possibility of utilization of insufficient amount of heat from geothermal sources during the periods with low outside air temperatures. Crucial for these analyses is modelling of the necessary yearly energy requirements for greenhouse heating. The results of these analyses enable calculation of an appropriate storage tank capacity so that the energy efficiency of greenhouse heating system with geothermal energy could be significantly improved.

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Environmental and Economic Benefit Analysis of an Integrated Heating System with Geothermal Energy—A Case Study in Xi’an China

Energies ◽

10.3390/en10122090 ◽

2017 ◽

Vol 10 (12) ◽

pp. 2090 ◽

Cited By ~ 4

Author(s):

◽

Keyword(s):

Geothermal Energy ◽

Economic Benefit ◽

Heating System ◽

Benefit Analysis

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Renewable Energy Sources in a Post-Socialist Transitional Environment: The Influence of Social Geographic Factors on Potential Utilization of Very Shallow Geothermal Energy within Heating Systems in Small Serbian Town of Ub

Applied Sciences ◽

10.3390/app10082739 ◽

2020 ◽

Vol 10 (8) ◽

pp. 2739 ◽

Cited By ~ 1

Author(s):

Nikola Jocić ◽

Johannes Müller ◽

Tea Požar ◽

David Bertermann

Keyword(s):

Climate Change ◽

Renewable Energy ◽

Geothermal Energy ◽

Renewable Energy Sources ◽

Heating System ◽

Energy Sources ◽

Wide Range ◽

Energetic Stability ◽

Shallow Geothermal Energy ◽

Very Shallow Geothermal Energy

Energetic stability is a precondition for a regular functioning of society and economy. Actual climate change raised the awareness of population and policy makers about the importance of exploited energy sources. Renewable energy sources are revealed as the solution which should satisfy both needs—a need for energetic stability, as well as a need for producing ‘clean’ and ‘sustainable’ energy, and therefore reduce humans’ influence on the climate change. Very shallow geothermal energy offers wide range for utilization, among others for heating and cooling living spaces. This article shows potentials of low temperature heating system networks in a small Serbian town of Ub. In addition to technical possibilities, this article combines geographical and social, as well as political and economic circumstances in the town of Ub, which emerge as a result of a complex (post-socialist) transitional vortex.

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