Experimental analysis of a solar absorption system with interior energy storage

2012 ◽  
Vol 23 (2) ◽  
pp. 39-49 ◽  
Author(s):  
Bilsay Pastakkaya ◽  
Nurettin Yamankaradeniz ◽  
Omer Kaynakli ◽  
Salih Coskun ◽  
Recep Yamanakaradeniz
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Heat Pump ◽  
Electric Heater ◽  
Cooling Power ◽  
Absorption System ◽  
Solar Absorption ◽  
Test Room ◽  
Daily Average ◽  
Absorption Cooling

This study examines experimentally the cooling application of a solar absorption system with interior energy storage that uses two different auxiliary systems. The experiments were performed at Uludag University, Bursa, Turkey on the 3rd and 4th of August 2010 that had the approximately same average outdoor temperature, 31°C. A solar hot water was delivered via a 40 m2 array of flat plate solar collectors that drove a lithium chloride (LiCl) absorption heat pump with a cooling power peak of 20 kW. A solar-powered air conditioning system was designed for heating and cooling in a test room that had a total floor space of 30 m2. Chilled water produced in the evaporator was supplied to the fan coil units, and the heat of condensation and absorption was rejected by means of a wet cooling tower. An electric heater and an air source heat pump were used as auxiliary systems for the absorption cooling application for two different cases when the solar energy was insufficient. Temperature variations were recorded for the absorption machine components, the test room, and the outdoors. The cooling energy, thermal energy, and daily average coefficient of performance (COP) of the absorption system were calculated for two days. Solar absorption cooling was considered for two different auxiliary systems and is presented in this manuscript. The results showed that the daily average COP of the absorption system was 0.283 for Case 1 and 0.282 for Case 2. For both cases, the interior energy storage of the absorption system enabled it to satisfy the cooling demand during the night while solar energy was not available.

Experimental Analysis of a Solar Energy Storage Heat Pump System

2021 ◽  
Author(s):  
Haifei Chen ◽  
Guiqiang Li ◽  
Yueyue Ling ◽  
Jie Fu ◽  
Yunjie Wang ◽  
...  
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Heat Pump ◽  
Experimental Analysis ◽  
Pump System ◽  
Heat Pump System ◽  
Solar Energy Storage

Designing a novel solar-assisted heat pump system with modification of a thermal energy storage unit

2019 ◽  
Vol 233 (5) ◽  
pp. 588-603 ◽  
Author(s):  
Mustafa Aktaş ◽  
Meltem Koşan ◽  
Erhan Arslan ◽  
Azim Doğuş Tuncer
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Heat Pump ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Solar Collector ◽  
Working Fluid ◽  
Storage Unit ◽  
Heating Systems ◽  
Energy Storage Unit

The integrated usage of solar energy systems, heat pump applications, and thermal energy storage units is an effective way for heating systems due to their sustainability and stability in operations. In this study, a novel direct solar-assisted heat pump with thermal energy system has been designed which uses the solar collector as the evaporator of the heat pump. Besides, two-dimensional transient numeric analyses have been conducted for the thermal energy storage unit using the ANSYS Fluent 16.2 commercial software package. With this direct system, the heat required for heating systems is supplied from the condenser with the heat received from the solar collector of the working fluid. For an effective and high performance system, the solar collector is designed as a double-pass which provided superheating of the working fluid. It is aimed to store the surplus energy from the solar energy in the thermal energy storage unit and to operate the system continuously and efficiently in both sunny and overcast weather conditions. Furthermore, the system has been analyzed theoretically and the results show that coefficient of performance may improve. As a result, this newly designed system can be successfully applied for thermal applications.

scholarly journals Assessment of Energy Storage Technologies and Systems Phase 2: Heat Pump and Solar Energy Applications

1978 ◽  
Author(s):  
J. Asbury ◽  
J. Caruso ◽  
R. Giese ◽  
R. Mueller ◽  
L. Akridge ◽  
...  
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Heat Pump ◽  
Phase 2 ◽  
Energy Applications ◽  
Storage Technologies

scholarly journals OPTIMAL WIND/SOLAR ENERGY MIX FOR RESIDENTIAL NET ZERO-ENERGY BUILDINGS

2018 ◽  
Author(s):  
Janar KALDER ◽  
Alo ALLIK ◽  
Hardi HÕIMOJA ◽  
Erkki JÕGI ◽  
Mart HOVI ◽  
...  
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Heat Pump ◽  
The Self ◽  
Zero Energy ◽  
Cover Factor ◽  
Zero Energy Building ◽  
Net Zero Energy ◽  
Net Zero Energy Building ◽  
Net Zero

The article is concentrated on the energy storage problems arising from microgeneration in private households. The case study involves a small-scale wind and solar electricity production set in a net zero-energy building. Both the net zero-energy building and the microgeneration units are connected to an utility grid. The current article serves to confirm the hypothesis, that the self consumption is at its maximum with the annual 70/30 wind and solar energy mix of in favour of the wind. The maximal self consumption at no additional energy storage in a net zero-energy building is studied as well. Produced and consumed energies are equal, which satisfies the requirements for a net zero-energy building with the utility grid acting as an energy buffer. The consumed energy is used to operate a heat pump, heat up ventilation supply air, run ventilation fans, supplying non-shiftable loads (white goods, TV, lighting etc), heat up domestic hot water via heat pump. To express self consumption, we use the term of supply cover factor, which describes optimally the directly consumed energy in relationship to net consumption or production. In annual scale, the cover factors for a net zero-energy building are equal as the production and consumption are equal as well. Also, seasonal variations in self consumption are studied. According to study results, the annual maximal supply cover factor in a net zero-energy building is 0.375 with 70/30 wind/solar mix. Seasonally, the self consumption is at its maximum in summer when the supply cover factor equals to 0.49.

scholarly journals Performance Analysis of Solar-Assisted Ground-Coupled Heat Pump Systems with Seasonal Thermal Energy Storage to Supply Domestic Hot Water for Campus Buildings in Southern China

2021 ◽  
Vol 13 (15) ◽  
pp. 8344
Author(s):  
Jin Zhou ◽  
Zhikai Cui ◽  
Feng Xu ◽  
Guoqiang Zhang
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Heat Pump ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Heat Balance ◽  
Solar Collector ◽  
Hot Water ◽  
Domestic Hot Water ◽  
Ground Coupled Heat Pump

The supply of domestic hot water (DHW) on college and university campuses is indispensable and is also one of the main components of campus energy consumption. The density of residential patterns and similar occupancy behavior of college students make it economical to use centralized systems to cover the DHW demand, and utilization of solar energy can make the systems more economical. Seasonal thermal energy storage (STES) is a promising key technology that can minimize the imbalance between the availability of solar energy and thermal energy demand. In this paper, a solar-assisted ground-coupled heat pump (SAGCHP) system that meets the DHW demand of 960 students was investigated by means of dynamic simulation and energy-economic analysis. The simulation results in terms of the underground heat balance are compared with a standalone GCHP system and a SAGCHP system without STES. Results show that heat recharging operations during university summer and winter breaks (when there are minimal students on campus) lead to improved underground heat balance and energy performance. Finally, a sensitivity analysis on system performance was carried out by varying solar collector arrays. It was found that there exists an optimal value of solar collector area to achieve the lowest system lifecycle cost (LCC).

Solar-Driven LiBr/H20 Air Conditioning System With a R-123 Heat Pump Assist

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
J. J. Rizza
Keyword(s):  
Solar Energy ◽  
Heat Pump ◽  
Air Conditioning ◽  
Solar Thermal ◽  
Fluid Temperature ◽  
Absorption System ◽  
Air Conditioning System ◽  
System Generator ◽  
Temporal Variance ◽  
System Water

This paper presents an energy system that utilizes solar energy to produce air conditioning with an absorption refrigeration system. Since there is often a temporal variance between the availability of the required solar energy and the demand for commercial building air conditioning, a liquid natural gas (LNG) subsystem is often used to supplement the solar-thermal array system. Because of operating cost consideration, this paper proposes the use of a R-123 heat pump to supply the required additional heat and temperature needed to effectively operate the absorption air conditioning system. Waste heat from the absorption system water condenser is used by the R-123 heat pump subsystem evaporator to supply the additional required heat at the appropriate temperature to the absorption system generator using the R-123 heat pump subsystem condenser. Under conditions when the pricing ratio of electric power and LNG is at certain level or when LNG is not available, the proposed R-123 heat pump subsystem offers a cost effective option. The solar-thermal collector array and R-123 heat pump are in a series just before the generator of the absorption system. The temperature differential between the absorption system water condenser temperature and the required absorption system generator temperature is relatively moderate, so that the coefficient of performance of the R-123 heat pump subsystem is sufficiently high to be a competitive alternative when compared to a LNG assist subsystem. Because of this moderate temperature difference, the proposed R-123 heat pump assist subsystem appears to be a better choice under certain conditions, than the use of LNG to raise the solar-thermal array transport fluid temperature to the required generator temperature when the solar-thermal array system fails to do so.

Sustainable Cooling with Hybrid Concentrated Photovoltaic Thermal (CPVT) System and Hydrogen Energy Storage

2018 ◽  
Vol 1 (2) ◽  
pp. 40-51 ◽  
Author(s):  
Muhammad Burhan ◽  
Muhammad Wakil Shahzad ◽  
Kim Choon Ng
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Optimization Algorithm ◽  
Concentration Ratio ◽  
Cooling System ◽  
Renewable Energy Sources ◽  
Hot Water ◽  
Hydrogen Energy ◽  
Adsorption Chiller ◽  
Back Plate

Standalone power systems have vital importance as energy source for remote area. On the other hand, a significant portion of such power production is used for cooling purposes. In this scenario, renewable energy sources provide sustainable solution, especially solar energy due to its global availability. Concentrated photovoltaic (CPV) system provides highest efficiency photovoltaic technology, which can operate at x1000 concentration ratio. However, such high concentration ratio requires heat dissipation from the cell area to maintain optimum temperature. This paper discusses the size optimization algorithm of sustainable cooling system using CPVT. Based upon the CPV which is operating at x1000 concentration with back plate liquid cooling, the CPVT system size is optimized to drive a hybrid mechanical vapor compression (MVC) chiller and adsorption chiller, by utilizing both electricity and heat obtained from the solar system. The electrolysis based hydrogen is used as primary energy storage system along with the hot water storage tanks. The micro genetic algorithm (micro-GA) based optimization algorithm is developed to find the optimum size of each component of CPVT-Cooling system with uninterrupted power supply and minimum cost, according to the developed operational strategy. The hybrid system is operated with solar energy system efficiency of 71%.

scholarly journals Bifunctional biomorphic SiC ceramics embedded molten salts for ultrafast thermal and solar energy storage

2021 ◽  
pp. 100764
Author(s):  
Qiao Xu ◽  
Xianglei Liu ◽  
Qingyang Luo ◽  
Yanan Song ◽  
Haolei Wang ◽  
...  
Keyword(s):  
Energy Storage ◽  
Solar Energy ◽  
Molten Salts ◽  
Solar Energy Storage ◽  
Sic Ceramics

scholarly journals Developing a Cold Accumulator with a Capsule Bed Containing Water as a Phase-Change Material

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2703
Author(s):  
Robert Sekret ◽  
Przemysław Starzec
Keyword(s):  
Energy Efficiency ◽  
Heat Pump ◽  
Cold Storage ◽  
Cooling Capacity ◽  
Cooling Power ◽  
Storage Process ◽  
Water Ice ◽  
Measurement Results ◽  
Mathematical Relationships ◽  
Change Material

The paper presents the investigation of a prototype cold accumulator using water–ice latent heat for the cold storage process. The concept of the cold accumulator was based on a 200-L-capacity cylindrical storage tank in which spherical capsules filled with water were placed. Beds of polypropylene capsules with diameters of 80 mm, 70 mm, and 60 mm were used in the tests. The cold accumulator operated with a water–air heat pump. Based on the test results, the following parameters were calculated: the cooling capacity, cooling power, energy efficiency of the cold storage, and energy efficiency ratio (EER) of the accumulator. The obtained measurement results were described with mathematical relationships (allowing for measurement error) using criterial numbers and the developed “Research Stand Factor Number” (RSFN) index. It has been found that, for the prototype cold accumulator under investigation, the maximum values of the cooling capacity (17 kWh or 85.3 kWh per cubic meter of the accumulator), energy efficiency (0.99), and EER (4.8) occur for an RSFN of 144·10−4. The optimal conditions for the operation of the prototype cold accumulator were the closest to laboratory tests conducted for a bed with capsules with a diameter of 70 mm and a mass flow of the water–glycol mixture flowing between the accumulator and the heat pump of 0.084 kg/s. During the tests, no significant problems with the operation of the prototype cold accumulator were found.

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