Adsorption Chiller Research Articles

Towards enhanced heat and mass exchange in adsorption systems: The role of AutoML and fluidized bed innovations

The selection of optimal design and the most efficient operational parameters for energy devices constitute a priority task for sustainable development and increasing energy efficiency within the net-zero emissions strategy. This is particularly important in adsorption cooling and desalination systems with poor performance due to unfavourable heat transfer conditions in conventional packed beds of adsorption chillers (ACs). Therefore, looking for additional ways of performance improvement is still challenging, especially covering different design variants and operational strategies. The existing complex, time-consuming and costly analytical, numerical and experimental methods, usually focused on a specific design and operating parameters of conventional packed adsorption beds, cannot tackle these comprehensive problems. Since artificial intelligence (AI) based models are considered tools that sometimes may overcome the shortcomings of the programmed computing approach and the experimental procedures, the paper introduces automated machine learning (AutoML) as a general approach for the design and optimization study of adsorption cooling and desalination systems. The double-effect, i.e. specific cooling capacity (SCP) and specific daily water production (SDWP) of various adsorption chillers (ACs) operating in large-, pilot- and small-scale adsorption cooling and desalination systems, is considered in the study. The paper also presents a novel big data optimization procedure for selecting the best operating and design strategy in adsorption cooling and desalination technology. Finally, a new concept of fluidized bed-type application in adsorption chillers is proposed, which allows for enhancing the performance of ACs.The presented approach can be referred to as a complementary design technique in adsorption cooling and desalination systems, besides the existing complex analytical and time-consuming numerical methods and expensive experiments.

Static Analysis of Low Temperature Waste Heat Driven Three-bed Adsorption Chillers Potential for Building Cooling Application

The adsorption cooling system is an environmentally friendly system because of non-CFCs (chlorofluorocarbons) and non-HCFCs (hydrochlorofluorocarbons). The simulation developed is an adsorption system that can operate with a low temperature waste heat source so that this adsorption system can be applied to building cooling systems. The purpose of this research is to obtain the most effective and efficient cycle of three bed silica gel-water adsorption system with a low temperature heat source so that it has the potential for building applications. The method developed is by simulating various design combinations of three bed adsorption systems and simulating 6 (six) cycle types. Furthermore, those designs of silica gel-water based two different types of three-bed adsorption chiller has been analyzed statically. The performance of the chillers was investigated in terms of coefficient of performance (COP) and specific cooling effect (SCE) for heat source temperature between 60oC and 90oC. The result first shows that the performance data of the proposed chillers (Cycle E and Cycle F) were compared with those of other four different types of three-bed adsorption chiller with the same operating conditions. It was observed that the proposed chillers provided a higher SCE compared with other four assorted chillers. Second result show that The Cycle B obtained the higher COP comparing with the other cycles designed in this study. Thus, this system has a good potential to be developed for building cooling systems by utilizing heat waste.

In-field monitoring and numerical parametric analysis of a small size adsorption solar cooling plant in Italy

Solar cooling of small buildings represents a very interesting potential market, still underdeveloped and characterized by a wide range of uncertainties, both on the technological and the economical side. Actually, there are a few low size ready-to-market adsorption/absorption chillers and their costs are significantly higher than technically mature compression systems. The combination of solar thermal systems with solar assisted chillers needs a thorough design stage to be correctly optimized and this may turn out unaffordable for a low size project. A monitoring campaign has been carried on a new building (PUEEL – Prototipo Uffici ad Elevata Efficienza in Legno, High Efficiency Wooden Office Prototype) realized at the facilities of IPLA1 in Turin, Italy. The building has a wooden highly insulated envelope, controlled mechanical ventilation with thermodynamic heat recovery, radiant heating/cooling. A solar thermal collector field is integrated in the building roof (Fig.1), used both for the building heating and cooling demand, thanks to a 9kW adsorption chiller. Dynamic simulations of the system, using software Polysun © for solar cooling plant and EnergyPlus © for building demand assessment, have also been carried on and compared with in-field measurements. The validated model has been used for a parametric evaluation of the effects of the installation of different components and control strategies.

Numerical Study of a Three-Bed Adsorption Chiller Employing an Advanced Mass Recovery Process with Different Cycles

In this paper, the performance comparison between two different cycles has been numerically studied. In cycle1, the configuration of beds in the three bed chiller with mass recovery were taken as uniform in size but in cycle2 the configuration of Hex3 is taken as half of Hex1 or Hex2 (where Hex1 and Hex2 are identical). In the present numerical solution, the heat source temperature variation is taken from 70°C to 90°C (for both cycle) and along with coolant inlet temperature at 30°C and the chilled water inlet temperature at 14°C. Silica gel-water is chosen as adsorbent-refrigerant pair. In the new strategy, if any one bed (3rd bed) is connect with the evaporator during pre-heating or pre-cooling time then it will give better performance than that of existing system. In this strategy, mass recovery process also occurs in all bed. Results show that the cooling capacity (CC) and coefficient of performance (COP) of the cycle1 is much better than that of the cycle2 in the range of heat source temperature from 700C to 900C.

Experimental Analysis of Fin Pitch Distance Variation of Adsorber for Adsorption Chiller Performance

The purpose of this study was to study the performance of silica gel-air adsorption chiller on two types of adsorber fins by conducting experiments at several cycle times, namely 500, 600, 700 and 800 seconds with specific mass recovery times, heat recovery times, and also variations on the input of the cooling fluid, so that optimal cycle times can be obtained related to COP and SCP. The adsorber fin-spacing which has more tightly fin distance does not determine the better performance of the adsorber for chiller application because the shorter distance of the fin, the cross-sectional area of the silica gel surface that has initial contact with the adsorbate will decrease so that the performance of the adsorber will decrease. The highest cooling capacity and COP obtained are 3.1 kW and 0.52, respectively. The results are obtained on adsorber with 3 mm fin distance and 700 s cycle with hot water inlet temperature of 79°C, cooling water inlet temperature of 29.4°C and chilled water outlet temperatures of 8.5°C

Implementation of Fluidized Bed Concept to Improve Heat Transfer in Ecological Adsorption Cooling and Desalination Systems

Sustainable development policy focuses on reducing the carbon footprint generated by the global industry and energy sector. Replacing conventional energy sources with environmentally friendly ones requires advanced research to increase energy efficiency and reduce the instability and intermittence of renewable sources. Moreover, adsorption chillers are an opportunity to introduce net-zero emission technologies to the refrigeration, air-conditioning, and desalination industries. Adsorption devices could be popularized if a method of effective heat transfer in the volume of the adsorption bed is developed. The innovative concept of introducing fluidized beds into the adsorption system can achieve the most promising results in improving energy efficiency. To confirm the adopted assumption, heat transfer coefficient calculations for the packed and fluidized bed were carried out in this paper based on experimental tests and literature data. The empirical research aims to extend the fundamental knowledge in the implementation of fluidization under low-pressure conditions, characteristic of the adsorption systems’ working cycle. Experiments were conducted on a unique test stand equipped with the Intensified Heat Transfer Adsorption Bed (IHTAB) reactor prototype. Five adsorption bed samples were analyzed. The reference sample consisted only of silica gel, and the subsequent ones contained aluminum or carbon nanotubes with 5 and 10% additions. In the case of samples with admixtures, the fluidized state increased the heat transfer coefficient on average from approx. 36.9 W/m2 K to approx. 245.4 W/m2 K.

Use of Ionic Liquid as Crystallization Inhibitor in Water-Lithium Bromide Absorption Chiller

Chillers are used in commercial buildings and industrial plants to provide air conditioning, refrigeration, and process fluid cooling. There are two basic types of chiller cycles: vapor compression and sorption. Sorption chillers are available as either absorption or adsorption designs, depending on the state of the sorbent. Absorption chillers use fluid refrigerants and absorbents (liquid or dissolved), while adsorption chillers employ a solid sorbent (typically silica gel) in combination with a fluid refrigerant. Among the former category, the use of highly hygroscopic LiBr salt as absorbent in combination with H2O as refrigerant comprises LiBr-H2O absorption chillers. Such chillers possess cooling capacities ranging from a few kilowatts (kW) to megawatts (MW) which match with small residential to large scale commercial or even industrial cooling needs. One of the major debilitating factors associated with LiBr-H2O absorption chillers is crystallization. A crystallization event causes a loss of cooling and requires de-crystallization by applying external heat, which results in extensive down-time and requires redundancy designed into a chiller plant. We investigated the use of the imidazolium-based ionic liquid, 1-butyl-3-methylimidazolium bromide ([BMIm]-Br), as crystallization inhibitor additive to LiBr-H2O in the ratio 1:19 [BMIm]-Br:LiBr. It was found that under the operating boundary conditions of 27°C/9°C (cooling water inlet temperature/chilled water outlet temperature), the LiBr-H2O absorption chiller can be operated without modifications and with around 10 K higher heating water inlet temperatures when adding [BMIM]-Br before crystallization occurs compared to pure LiBr-H2O solution. When using the [BMIM]-Br ionic liquid, the refrigeration capacity of the absorption chiller under the above operating conditions and at 85°C heating water inlet temperature exhibited 10% increase after optimizing the solution flow, that lead to higher outputs, such as lower cooling water temperatures. By adding the [BMIM]-Br to the aqueous lithium bromide solution the operating range of the absorption refrigeration system could also be extended to resorption mode, which allows refrigeration below 0 °C. Thus, there is an excellent potential for a significant extension of the application range of LiBr-H2O chillers, e.g. in the field of food cooling and refrigeration processes. Figure 1

4E analysis of photovoltaic thermal collector-based tri-generation system with adsorption cooling: Annual simulation under Moroccan climate conditions

Using solar photovoltaic thermal technology for tri-generation systems has gained increased interest. However, there is a dearth of literature on the assessment of this solar system integrated with adsorption chiller from a holistic 4E perspective. Hence, energy, exergy, economic and environmental analyses are performed along with sustainability assessment in Moroccan regions.The results revealed that the solar tri-generation system exhibited a promising performance, especially in hot desert region, achieving an energy efficiency of 50.07% due to the high insolation. The exergy analysis proved superior energy production quality in cold Mediterranean region, with an exergy efficiency of 15 %. Economically, the system could be considered cost-effective with a levelized cost of production reaching $0.074/$0.059 per kWh and a discounted payback period of 17.31/15.12 years in cold Mediterranean/hot desert regions. Moreover, in hot desert region, the system could mitigate 3.46 tCO2/m2 of solar collector, while in cold Mediterranean region it exhibits the best sustainability index of 1.18 due to high-quality energy production.Overall, the paper emphasizes the need for further research and advancement of this technology for a sustainable environment. Besides, it aims to offer engineers and researchers valuable insights into the potential of photovoltaic thermal-based tri-generation systems, especially in the building sector.

Review of Micro- and Nanobubble Technologies: Advancements in Theory and Applications and Perspectives on Adsorption Cooling and Desalination Systems

Adsorption refrigerators are a compelling ecological alternative to compressor refrigerators; global warming forces us to constantly look for alternative sources of energy and cold. Cold production in adsorption chillers is based on the use of heat generated by other processes running in the company. Waste heat from production processes, which has, until now, been irretrievably lost, is a potential source of energy for generating cold via an adsorption unit producing chilled water. Cooling optimizes the use of the heating network in summer and can lead to increased electricity production while reducing heat supply losses. Thus far, attempts to implement adsorption refrigerators for widespread use have not been successful as a result of the low efficiency of these devices; this is directly related to the poor heat and mass transfer conditions in the beds and heat exchangers of adsorption refrigerators. The solutions used so far, such as new working pairs, glued beds or modifications to the structure or cycle length, are still not strong enough for these devices. Therefore, it is necessary to look for new solutions. Using micro- and nanobubbles as media to increase mass and heat transfer in refrigerators is an innovative and pioneering solution. Thus, this document describes the most important features of micro- and nanobubble technology applications in adsorption refrigerators. This article is an introduction and a basis for the implementation of further research, consolidating the existing literature as a review.

Development and experimental study of a compact silica gel-water adsorption chiller for waste heat driven cooling in data centers

In recent years, data centers have experienced rapid construction, leading to a significant surge in energy consumption, and cooling systems have emerged as prominent energy consumers of data centers. Among the cooling technologies, liquid cooling allows higher cooling circuit temperatures and provides potential for heat recovery. As a thermally driven cooling technology, adsorption refrigeration systems offer an alternative way to compression refrigeration systems by utilizing low-grade waste heat from liquid-cooled circuits to produce chilled water for air-cooled components. In this study, a compact silica gel-water adsorption chiller is developed for a small modular data center and experimentally investigated under extremely low driving temperatures. Under the typical summer conditions with the hot/cooling/chilled water inlet temperatures of 50 °C/30 °C/23 °C, the adsorption chiller achieves the cooling power of 4.9 kW and the COP of 0.50. When the cooling water inlet temperature changes from 32 °C to 24 °C, both the cooling power and COP show significant improvements, from 3.04 kW to 10.50 kW and from 0.44 to 0.66, respectively. Moreover, the increase of the hot water inlet temperature from 48 °C to 56 °C can enhance the cooling power to some extent, while the chilled water inlet temperature has little influence on the performance. The experimental results demonstrate the feasibility and performance of the developed adsorption chiller in data center waste heat driven cooling. Besides, potential adsorbents and possible optimization strategies are presented for performance improvement based on adsorption potential method.

Feasibility Analysis on Compression-Assisted Adsorption Chiller Using Chlorides for Underground Cold Transportation

Thermal-driven refrigeration technologies, e.g., absorption- or adsorption-type, are gathering momentum since they can utilize low-grade heat from industrial, solar or geothermal energy. However, heat sources and end users are usually mismatched, which could lead to potential heat pollution and increased carbon emissions. Long-distance thermal energy transportation is good for district heating and cooling, which is of great significance if it can achieve a high energy-transportation density and low heat loss. In this paper, a compression-assisted chemisorption chiller driven by a low-temperature heat source for cold transportation is initially proposed, which aims to transport liquid ammonia with chemical potential and generate a cooling effect for end users. A feasibility analysis of the compression-assisted chemisorption chiller is preliminarily performed for 2 km cold transportation. The results show that the highest theoretical coefficient of performance and the energy efficiency of the compression-assisted adsorption chiller using a sodium bromide–ammonia working pair can reach 0.46 and 0.25, respectively, when the evaporation temperature is 20 °C. Among the three selected low-temperature salts, ammonium chloride–ammonia shows the best performance, which is up to about 40% higher than those of sodium bromide–ammonia and barium chloride–ammonia. It is demonstrated that compared with common absorption chillers, a compression-assisted adsorption system has a reasonable working efficiency to transport cold energy when the low- or ultralow-temperature heat source, e.g., lower than 60 °C, is required to be utilized.

Solar-Powered Adsorption-Based Multi-Generation System Working under the Climate Conditions of GCC Countries: Theoretical Investigation

In this study, transient modelling for a solar-powered adsorption-based multi-generation system working under the climatic conditions of the Gulf Cooperation Council (GCC) countries is conducted. Three cities are selected for this study: Sharjah in the United Arab Emirates, Riyadh in Saudi Arabia, and Kuwait City in Kuwait. The system comprises (i) evacuated tube solar collectors (ETCs), (ii) photovoltaic-thermal (PVT) solar collectors, and (iii) a single-stage double-bed silica gel/water-based adsorption chiller for cooling purposes. A MATLAB code is developed and implemented to theoretically investigate the performance of the proposed system. The main findings of this study indicate that among the selected cities, based on the proposed systems and the operating conditions, Riyadh has the highest cooling capacity of 10.4 kW, followed by Kuwait City, then Sharjah. As for the coefficient of performance (COP), Kuwait City demonstrates the highest value of 0.47. The electricity generated by the proposed system in Riyadh, Kuwait City, and Sharjah is 31.65, 31.3, and 30.24 kWh/day, respectively. Furthermore, the theoretical results show that at 18:00, the overall efficiency of the proposed system reaches about 0.64 because of the inclusion of a storage tank and its feeding for the adsorption chiller. This study analyzes the feasibility of using a combination of ETCs and PVT collectors to drive the adsorption chiller system and produce electricity in challenging weather conditions.

Dynamic performance analysis of a solar adsorption system: the effect of operating conditions and collectors’ area

A continuous adsorption refrigerator, aiming for cold production to a fruit storage room installed in arid regions, is proposed. After cooling load estimation, a technical-economic study of different types of solar collectors was performed. Then, the dynamic performances of a solar-driven two-bed adsorption chiller are studied. Furthermore, this study shows that an optimal choice of the collector-type area and the operating conditions can reduce the global system cost and ensure better energy management. With 43.47 m 2 collectors’ area, a solar fraction of 55% is reached at cycle time (tcycle) 1600s; however, 49% is obtained at tcycle of 900s. With a total collectors’ area of 43.47 m2, a tcycle of 1600s and a cooling water inlet temperature (TCW,in) of 22°C, 60% of the cooling demand is solar produced. However, 57% is achieved at a tcycle of 900s, 50.61 m2 collectors’ area and TCW,in of 25°C. Highlights The cooling load of a storage room used for indigenous fruit preservation was estimated. A technical-economic study of different types of solar collectors is carried out to choose the most suitable one. A detailed dynamic approach to the thermodynamics of a solar adsorption refrigerator according to the time-varying solar radiation intensity and climatic data were presented. The effect of solar collectors’ area and different operating conditions has been studied to optimise the global system performance and cost.

Performance analysis and PCM selection for adsorption chiller aided by energy storage supplied from the district heating system

Performance analysis and PCM selection for adsorption chiller aided by energy storage supplied from the district heating system

Modelling and performance assessment of a two-bed adsorption chiller at different operating conditions

The study aims to assess the performance of an adsorption chiller using the Maxsorb III-methanol as an adsorbent pair. A modified transient lumped parameter model was developed to evaluate the dynamic behavior of the system at various operating parameters. Methanol is used as refrigerant as it has a significant latent heat of evaporation, high normal boiling point, low melting point and environmentally friendly. The results showed that the modified transient lumped parameter model can predict well the dynamic behavior of the adsorption chiller under different operating conditions. The system was able to produce about 13.65 kW (227 W kg-1) cooling capacity with a thermal COP of 0.73 at 85 and 30 oC driving source and cooling temperatures respectively. In addition, simulation tests were made to compare the performance of the Maxsorb III-methanol system with the different working pairs at the same physical dimensions of the present system components and operating parameters. At heat source temperatures of 85 oC which can be gained from waste heat or solar energy, the COP of the Maxsorb III-methanol cycle was about 12.0%, 44.0% and 6.6% higher than that of ACF-ethanol, silica-gel-water and activated charcoal/methanol cycles. The Maxsorb III/methanol adsorption cycle can work effectively with low grade heat sources, which can be gained from renewable energy or waste heat sources.

Modelling and performance assessment of a two-bed adsorption chiller at different operating conditions

The study aims to assess the performance of an adsorption chiller using the Maxsorb III-methanol as an adsorbent pair. A modified transient lumped parameter model was developed to evaluate the dynamic behavior of the system at various operating parameters. Methanol is used as refrigerant as it has a significant latent heat of evaporation, high normal boiling point, low melting point and environmentally friendly. The results showed that the modified transient lumped parameter model can predict well the dynamic behavior of the adsorption chiller under different operating conditions. The system was able to produce about 13.65 kW (227 W kg-1) cooling capacity with a thermal COP of 0.73 at 85 and 30 oC driving source and cooling temperatures respectively. In addition, simulation tests were made to compare the performance of the Maxsorb III-methanol system with the different working pairs at the same physical dimensions of the present system components and operating parameters. At heat source temperatures of 85 oC which can be gained from waste heat or solar energy, the COP of the Maxsorb III-methanol cycle was about 12.0%, 44.0% and 6.6% higher than that of ACF-ethanol, silica-gel-water and activated charcoal/methanol cycles. The Maxsorb III/methanol adsorption cycle can work effectively with low grade heat sources, which can be gained from renewable energy or waste heat sources.

Water, ethanol, or methanol for adsorption chillers? Model-based performance prediction from Infrared-Large-Temperature-Jump experiments

Adsorption chillers are a promising technology to ease the burden on renewable electricity demand by using waste heat as driving energy. Their performance depends on the adsorbent’s kinetics, the chosen refrigerant, the design of the adsorber, and the selected temperatures. Thus, quantifying an adsorption chillers’ performance usually requires expensive experiments at full scale. Here, we efficiently characterize a broad set of working pairs for a wide range of conditions using a two-step approach: First, we conducted Large-Temperature-Jump and equilibrium experiments to extract kinetic and equilibrium parameters of water, ethanol, and methanol with a set of currently discussed adsorbents. Second, we inserted the parameters into a dynamic Modelica model to evaluate the working pairs’ performance in full-scale two-bed adsorption chillers. For chilling above 0 °C, water remains the benchmark refrigerant with the highest volumetric power and efficiency with the silica gels SG123 and Siogel. Ethanol and methanol working pairs offer higher mass transfer coefficients, but could not offset the benefits of water. Coatings of the MOFs aluminum fumarate and CAU–10–H provided exceptionally high heat transfer coefficients, but were too thin to compete. For chilling below 0 °C, ethanol and methanol were on par. ZIF–8 was competitive with the activated carbon CarboTech A35. Overall, CarboTech A35/methanol showed broad applicability, performing comparably to SG123/water above 0 °C while still providing reasonable performance below 0 °C.

Ammonia Adsorption Performance of Zeolitic Imidazolate Frameworks for Cooling.

Promoting the cooling performance of adsorption chillers (ACs) greatly relies on the exploration of high-performance adsorbent/refrigerant working pairs. Ammonia is not only an environmentally friendly refrigerant but also favorable for heat and mass transfer in ACs owing to its large vapor pressure and enthalpy of evaporation. Zeolite imidazolate frameworks (ZIFs) with excellent ammonia stability are identified as a class of potential adsorbents for practical ammonia-based ACs. However, high-performing ZIF/ammonia working pairs with excellent AC performance are still to be developed. In this work, the cooling performance including the coefficient of performance for cooling (COPC) and the specific cooling effects (SCEs) of 26 ZIFs with the same composites but different topologies was evaluated by combining molecular simulation and mathematical modeling. Five high-performing ZIFs with COPC > 0.45 and SCE > 250 kJ/kg were identified, among which gis-ZIF with the highest COPC of 0.51 and lta-ZIF with the highest SCE of 354 kJ/kg both are promising to be synthesized and applied further. Besides, the quantitative structure-performance relationship (QSPR) was extracted that can help quickly identify and design high-performing ZIFs according to their ammonia adsorption isotherms and structural characteristics. Moreover, "S"-shaped adsorption isotherms with high saturation adsorption capacity (>0.2 g/g), suitable step position (0.2-0.4), and relatively low Henry's constant (<1 × 10-5 mol/(kg·Pa)) are more favorable for excellent COPC and SCE. From the perspective of structure characteristics, ZIFs possessing low crystal density (<0.9 g/cm3), high accessible surface area (>2000 m2/g), balanced largest cavity diameter (∼15 Å), and accessible pore volume (∼0.65 cm3/g) are beneficial for high-efficient cooling performance.

Dynamics of water vapour sorption on composite LiCl/(silica gel): An innovative configuration of the adsorbent bed

Adsorption Heat Conversion (AHC) is energy and environment saving alternative to conventional compression systems. The growth of specific power of AHC systems is a prerequisite for the wider spreading of AHC. To enhance the power, an innovative adsorbent bed configuration was suggested, namely, a compact adsorbent layer prepared by gluing to heat exchanger surface ready-made grains instead of uniform adsorbent coating. The main goal was a comparative study of water sorption dynamics on loose and glued grains of a composite LiCl/(silica gel) to evaluate the power enhancement. The grains were glued to aluminium foil with various binders, both organic and inorganic, the effect of the binder nature was studied. The effective heat transfer coefficient was evaluated under typical conditions of adsorption chilling cycle. The main findings are: (a) the effective heat transfer coefficient is increased up to 1.5 times when using inorganic binders; (b) organic binders do not affect heat transfer; (c) heat transfer intensification leads to accelerating initial stage of the ad/desorption; (d) at longer times, a desorption slowdown is observed due to hindered mass transfer or LiCl crystallisation. The factors controlling the adsorption kinetics are determined and recommendations are formulated for designing innovative bed configuration.

Simulation study of R134a based vapour compression-adsorption hybrid chiller with activated carbon as adsorbent

Vapour adsorption is one of the viable routes for producing refrigeration from low-grade thermal energy. This paper presents the simulation study of a proposed novel hybrid chiller combining a R134a based vapour compression refrigeration (VCR) chiller with a single-bed vapour adsorption (VAd) chiller. The proposed system layout leads to minimal thermal inventory and it also ensures that the VAd system can be integrated with any pre-existing R134a VCR system. The performance of proposed hybrid chiller is compared with the standalone VCR system. Maxsorb-III (MX-III) and a low cost Coconut shell based activated carbon (CSAC) are chosen as the two adsorbents for this comparative study. When compared to standalone VCR system, the hybrid system shows a maximum increment of 50% and 9% in peak refrigeration capacity for 30 kg MX-III and CSAC as adsorbents respectively. Time-averaged specific cooling capacity (SCC) and COP ratio of hybrid to standalone VCR system is used as performance parameters in the present study to evaluate optimum adsorption time, which lies between 450 and 750 s. This paper also presents the evaluation of practical minimum desorption heat source temperature of the hybrid system. For both the adsorbents, minimum desorption temperature lies in the range of 62–71 °C making this hybrid system suitable for both industrial waste heat as well as non-concentrating type solar based heat source.