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[Display omitted] • A novel cooling system with a simple design was developed. • The system is based on fluid piston machines and solar collector. • The system was tested on a solar radiation simulation test rig. • The experimental performance results of the system are analysed. • The prototype's performance is comparable to that of main existing technologies. The development of novel and improvement of existing technologies for utilising solar thermal energy for cooling purposes traditionally attracts increased attention in both industry and academia. This work presents the development of a novel cooling system with a simple design and direct utilisation of solar thermal energy. The cooling system combines a liquid piston engine and cooling machine and is driven by an evacuated tube solar collector. A prototype of such the system was designed, built and tested in laboratory conditions using a solar radiation simulator. Variations in pressures, temperatures, and the fluid piston oscillation amplitudes in the system during its operation were recorded, and the indicated power of the engine and cooling capacity of the system were determined for a range of operation and design parameters. For the heat input range of 700–900 W and the constant temperature of the cooling water equal to 26.0 °C, the engine indicated power and cooling capacity of the system varied in the range of 70.0–88.0 and 51.0–61.0 W. The corresponding indicated efficiency of the engine and cooling system were in the range of 10.0–9.7 and 7.2–6.7%. The temperature in the cooling chamber was registered in the range of 20.0–18.2 °C at an ambient temperature of 24.0 °C. The COP of the cooling machine decreased from 0.71 to 0.69. The system performance improved in tests with a constant heat input (700 W) and reducing cooling water temperature. For cooling water temperature reduction from 26.0 to 18.0 °C, the engine indicated power and cooling capacity of the system varied in the range of 70.0–111.9 and 51.0–72.0 W. The corresponding indicated efficiency of the engine and cooling system were in the range of 10.0–16.0 and 7.2–10.3%. The COP of the cooling machine decreased from 0.71 to 0.64. The temperature in the cooling chamber was registered in the range of 20.0–14.4 °C at an ambient temperature of 24.0 °C. Experimental results obtained using the system's initial design demonstrate that the engine has efficiency comparable to low-temperature steam and Organic Rankine Cycle turbines. The Coefficient of Performance of the system is similar to that of single-stage absorption chillers. [ABSTRACT FROM AUTHOR]

• Solar energy and PCM are used to augment the indoor steam curing process. • Mathematical model of the curing process is developed. • Comparison with experiments confirms the accuracy of the mathematical modelling. • Benefits of the proposed technology are quantitively demonstrated. Steam is used to provide heating and moisture in the curing process for the production of precast concrete (PC) construction elements. The generation of steam requires large amounts of fossil fuels. This study considers the incorporation of solar thermal energy into the steam curing of PC construction elements for reducing the need for fossil fuels and associated CO 2 emissions. For this purpose, the board made of composite phase change material covers the inner surface of the main sun-facing wall in the heating & curing building. The PCM board is heated by sun rays and accumulates thermal energy during the PCM's phase transition, and this energy then is released to the indoor environment of the building, reducing the amount of steam required to maintain a certain level of temperature during the curing process. The energy consumption simulation software, EnergyPlus, and two physical models (built on the scale of 1:3) were used to study the effects of two different PCMs on the thermal performance of such new type of heating & curing buildings. Composite PCMs considered were GH-33 and GH-37 with 33 and 37 °C melting temperatures developed by the research team. The theoretical and experimental results are in good agreement and demonstrate that, compared to the GH-33, GH-37 PCM increases the temperature of the inner surface of the main sun-facing wall and the upper surface temperature of the PC construction element by 3.4 and 1.4 °C, respectively. The heat accumulation and discharge rates also were greater by 62%. For the investigated design of the building and given location in China, the deployment of studied PCM wall panels results in a reduction in the annual energy consumption and CO2 emissions by 58.6 GJ and 5 tons, respectively. The method developed for applying solar energy and selecting PCMs for augmenting steam curing of PC construction elements can be deployed in different geographical regions. [ABSTRACT FROM AUTHOR]