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This paper reports about the combined experimental and numerical investigation of a novel small size multi-generation system, for electric (i.e.

The energy demand of industries accounts for about 30–35% of world yearly energy consumption, a relevant percentage is due to the need of heating and cooling demand. Solar heating and cooling technologies can be integrated in industrial processes to reduce the fossil fuels consumption as well as the related greenhouse gas emissions. This paper reports the experimental analysis of a novel hybrid sorption-compression chiller for cooling and refrigeration purposes in cascade layout, which uses silica gel/water for the sorption cycle and a low Global Warming Potential (GWP) refrigerant, i.e. propylene for the compression cycle. The experimental results highlighted the flexibility of the system in terms of performances and operating conditions, these were compared to the theoretical performances and it was found out that electricity energy savings from 15% to 25% can be achieved when using the hybrid system over a compression one with the same cooling capacity. The results were converted in performance maps and processed in a statistical model, in order to get a simplified expression for determining the overall performances of the hybrid system through variables that could be measured by a final user, such as the operating temperatures. Optimization strategies were identified for a further enhancement of the performance of the chiller, i.e. the reduction of the electricity consumption, by controlling the intermediate temperature (evaporation temperature of the sorption chiller) through sorption cycle management and the use of variable speed of the pumps in all the circuits to reduce the parasitic consumption especially at low part loads.

In the present paper design, realization and testing of a novel small scale adsorption refrigerator prototype based on activated carbon/ethanol working pair is described. Firstly, experimental activity has been carried out for identification of the best performing activated carbon available on the market, through the evaluation of the achievable thermodynamic performance both under air conditioning and refrigeration conditions. Once identified the best performing activated carbon, the design of the adsorber was developed by experimental dynamic performance analysis, carried out by means of the Gravimetric-Large Temperature Jump (G-LTJ) apparatus available at CNR ITAE lab. Finally, the whole 0.5 kW refrigerator prototype was designed and built. First experimental results both under reference air conditioning and refrigeration cycles have been reported, to check the achievable performance. High Specific Cooling Powers (SCPs), 95 W/kg and 50 W/kg, for air conditioning and refrigeration respectively, were obtained, while the COP ranged between 0.09 and 0.11, thus showing an improvement of the current state of the art.

This paper presents a new experimental setup devoted to measure the ad-/desorption kinetics of an Ad-HEX (adsorbent + heat exchanger) under typical boundary conditions of an Adsorption Heat Transformer (AHT) as well as the results of the first test campaign carried out. The experimental apparatus can be considered as a gravimetric version of the known Large Temperature Jump method. In fact, the dynamic evolution of the uptake during the isobaric ad-/desorption stages is directly measured by a weighing system suitable to work in the range of 5–600 g of sample mass (adsorbent + HEX) with the accuracy ±0.1 g and the time response shorter than 0.1 s The experimental campaign was conducted on an Ad-HEX composed of granules of a commercial SAPO-34 adsorbent placed on a flat type aluminum HEX, under operating conditions reproducing two different thermodynamic cycles (Th = 90 °C, Te = 10 °C, Tc = 30 and 35 °C), typical for adsorption air conditioning. The influence of the grain size (ranging from 0.350 to 2.5 mm) on the adsorption dynamics both in monolayer and multilayer configurations at variable and constant “heat transfer surface/adsorbent mass” ratios (S/m) was studied. The results showed that, for the Ad-HEX configurations tested, the adsorption dynamics can be properly described by a modified Linear Driving Force approach by the use of a single temperature-invariant characteristic time τ. The invariance of the specific cooling power was revealed when the S/m ratio was kept constant (S/m = 1.23 m2/kg). This ratio is found to be a useful parameter for both assessment of the dynamic perfection and optimization of various Ad-HEX configurations.