Experimental comparative study on thermal performance of latent heat storage tanks with pin, perforated, and rectangular fins at different orientations

Thermal Science and Engineering Progress, Journal Year: 2024, Volume and Issue: 48, P. 102401 - 102401

Published: Jan. 13, 2024

The low thermal conductivity of phase change materials (PCMs) has limited their widespread use in practical applications. In the present study, different fin structures, namely, rectangular, perforated, and pin were examined to analyze performance melting process rectangular latent heat storage tanks. Experiments performed at both horizontal vertical orientations evaluate effectiveness configurations. Visual observation evolution time intervals was enabled through a transparent plexiglass shell. Instantaneous transfer rate energy measured using thermocouple readings photographs. results show that maximum coefficient between heated wall PCM is obtained by pin-finned tank followed perforated rectangular-finned This behavior justified intensification upward convection flows voids provided fins or fins. Although structure lowest convective coefficient, its slightly higher than other structures due larger area. At temperature 70℃, configuration are respectively 25% 4% less those fin. It reveals provides most effective area compared counterparts which have significantly volume. addition, it found regardless configuration, formation more vortical flow within molten PCM. unfinned finned tanks implying orientation should be well-chosen minimize along with adding various

Language: Английский

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Long-term thermal performance analysis of a large-scale water pit thermal energy storage

Journal of Energy Storage, Journal Year: 2022, Volume and Issue: 52, P. 105001 - 105001

Published: June 1, 2022

Large-scale water pit thermal energy storage (PTES) promotes solar district heating (SDH) system as one of the most potential renewable applications for carbon neutrality. PTES needs vast investment and operates in a complicated with numerous components, highlighting need suitable simulation tool tech-economic feasibility investigations. This paper experimentally theoretically investigated long-term performance 60,000 m3 Dronninglund, Denmark. Five years measurements were analyzed to investigate development temperatures, heat flows, stratification storage. A modified 2D model was proposed calculate large-scale based on XST TRNSYS. The results showed that developed predicts well temperatures flows. For one-year validation, deviations annual charged/discharged energy, internal content, loss between 2.0%/1.8%, 2.8% 1.3%, respectively. Dronninglund 90.1% efficiency five-year investigation due its high utilization cycle 2.16. Even without any insulation sidewall bottom PTES, average from two parts only accounted 32.3% total loss. Meanwhile, soil region needed four stabilize. Approx. 24.4% summer is regained by winter, when there low temperature findings serve good reference designers practitioners

Language: Английский

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Solar district heating system with large heat storage: Energy, exergy, economic and environmental (4E) analysis

Energy Conversion and Management, Journal Year: 2024, Volume and Issue: 314, P. 118709 - 118709

Published: June 22, 2024

Language: Английский

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Techno-economic evaluation of waste heat recovery from an off-grid alkaline water electrolyzer plant and its application in a district heating network in Finland

Energy, Journal Year: 2024, Volume and Issue: 306, P. 132181 - 132181

Published: June 25, 2024

The expected extensive production of hydrogen through water electrolysis will generate a substantial quantity industrial waste heat. Waste heat recovery from electrolyzer facilities would provide significant potential for renewable generation into district heating (DH) networks. This paper investigates the techno-economic recovering an off-grid alkaline (AWE) plant and using in DH network under Nordic conditions. A system that includes pumps, pit thermal energy storage (PTES) electric boiler is modeled component capacities are cost-optimized four different scenarios with varying demand coverage rates. AWE based on measurements conducted southeastern Finland. It was found even 100 % rate, levelized cost (LCOH) be 44 €/MWh. Heat pumps constitute largest single while share PTES LCOH varies between 11 19 %. results were compared estimated capacity Finland, leading to conclusion by 2040, there could fulfill entire country.

Language: Английский

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Solar thermal vs. PV with a heat pump: A comparison of different charging technologies for seasonal storage systems in district heating networks

Energy Conversion and Management X, Journal Year: 2024, Volume and Issue: 22, P. 100564 - 100564

Published: March 12, 2024

The majority of district heating networks (DHNs) in Germany and other European countries are still supplied by fossil fuels. While several possible technical solutions exist to decarbonize DHNs, the problem is availability solar energy – thermal electric or renewable sources during winter. A solution shift available from summer winter using seasonal storage systems. Especially pit systems (PTES) have shown an economic advantage compared types. Therefore, we would like further investigate design PTES under different techno-economic conditions. In this study, charging options for were examined. Solar was photovoltaic (PV), supplying air-source heat pump (ASHP). We developed open-source Python package based on mixed-integer linear programming, minimizing total system cost, i.e., annuity, including opex capex. tool selects, operates, designs converters storages. Furthermore, it optimizes network's capacity operation. optimization takes characteristics existing DHN as input supply across locations (LOCs). model separates hydraulic calculation builds up a multi-stage process consider temperatures inside network PTES. applied Eastern Germany. results show low sensitivity electricity price all concepts. Operating at negatively affects capacity, therefore, best suited high-temperature networks. concept PV with ASHP better densely populated regions. However, both concepts cost above 20 ct/kWh area over 120 €/m2. For ca. 19 ct/kWh, below 17

Language: Английский

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Integration of curtailed wind into flexible electrified heating networks with demand-side response and thermal storage: Practicalities and need for market mechanisms

Energy Conversion and Management, Journal Year: 2024, Volume and Issue: 304, P. 118203 - 118203

Published: Feb. 19, 2024

Increasingly high renewable penetration in electrified energy systems causes increasing levels of curtailment that must eventually be mitigated. System flexibility, storage and demand-side response the form flexible heating cooling demands are efficient solutions for mitigation, however challenges remain such as economic benefits financial impacts mitigation on consumers, among others. In this paper curtailed wind energy, incentivised with discount payments, through networks thermal is investigated a genetic optimisation algorithm, results analysed terms overall costs, technical feasibility level use from perspective network operator consumer. It found large-scale lowers cost increases integration, allows district to run almost entirely otherwise (up 97.0 % example considered here). However without adequate market mechanisms, financially beneficial all stakeholders only at low levels; split approach, incentives or mechanisms necessary higher of, more efficient, mitigation.

Language: Английский

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Case study on combined heat and water system for district heating in Beijing through recovery of industrial waste heat in Tangshan

Energy, Journal Year: 2024, Volume and Issue: 300, P. 131316 - 131316

Published: April 14, 2024

Language: Английский

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Charging performance of structured packed-bed latent thermal energy storage unit with phase change material capsules

Journal of Energy Storage, Journal Year: 2023, Volume and Issue: 71, P. 108157 - 108157

Published: June 27, 2023

Language: Английский

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Novel solar-driven low temperature district heating and cooling system based on distributed half-effect absorption heat pumps with lithium bromide

Energy, Journal Year: 2023, Volume and Issue: 270, P. 126884 - 126884

Published: Feb. 6, 2023

Language: Английский

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Improved heat transfer mathematical model forpyramid shaped seasonal heat storage water pit and the influence of boundary conditions

Applied Thermal Engineering, Journal Year: 2024, Volume and Issue: 252, P. 123672 - 123672

Published: June 12, 2024

Language: Английский

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