Super-cool temperature for industrial processes with solar heat
Concentrated solar power CSP systems literally concentrate sunlight onto a receiver where the power collected from the sun is converted into heat. Among all the CSP technologies, HyCool is developing its concept based on the cheap and easy-to-install linear Fresnel system. Consisting of a large number of simple mirrors in parallel rows, these mimic a large Fresnel lens to maximise energy collection.
A hybrid – the pump with synergy
The prime mission of the EU-funded HyCool project is to increase the use of solar heat in industrial processes. “We have developed a new Fresnel CSP solar thermal collectors (FCSP) system with specially tailored hybrid heat pumps (HHPs),” says Silvia Jané, HyCool’s project coordinator. “The ‘two-in-one’ combination of adsorption- and compressor-based heat pumps results in a wider output temperature range, enabling both industrial heating and cooling powered by the sun,” Jané explains. By increasing the flexibility of the system configuration, the objective is to extend the range of application of solar heat in industrial processes with temperatures ranging from 5 °C to 240 °C. “Incorporating a wide range of design and operational configurations, we have increased the number of use scenarios for solar heat in industrial environments,” Jané emphasises. The proposed system improves the adsorption technologies for cold generation – coupled with increased compactness and plug and play features. This also provides seamless integration with other conventional sources such as electrical energy, resulting in a higher deployability of solar heat in industrial processes (SHIP). Moreover, when the HHPs developed in HyCool are driven by solar or waste heat and embedded in real industrial thermal processes, they can achieve twice the coefficient of performance of conventional heat pumps and further improve the overall process efficiency. Component optimisation and final design of the full-scale modular solar HHP and its manufacture and commissioning have been completed. A characterisation protocol for the properties of different adsorber materials such as thermal diffusivity, heat capacity, adsorption behaviour, vapour transport properties and heat of adsorption at different temperatures and pressures has also been developed and will lead to an extensive material testing campaign to select the best candidate for real case applications.
Energy winners in industry and food sectors
“The biggest challenge facing the HyCool project was to obtain a valid configuration for the two pilots based on the first design of the modular heat pump and the hydraulic schematic as well as the specifications for each demonstration site,” Jané comments. This key step has now been achieved, and field work has enabled a full display of energy profiles. At the Spanish production site of consortium partner Givaudan, a flavours and fragrances company, the HyCool concept has been applied to several processes with either heating or cooling needs. Givaudan’s current cold installation makes use of a glycolic water chiller to keep the water entering the liquid ring of the vacuum pumps at 7 °C, with a thermal demand of 125.5 kW. ”For the use cases considered, the electrical consumption of the compression chiller will be reduced by 29 % (spring) and 44 % (summer), respectively, by using HyCool technology,” says Jané. This efficiency gain is even higher if compared to common refrigeration systems. Another prototype applies the HyCool concept to specialised small food industries with cooling needs in their processes and will be tested at Bo de Debò SL in Spain. Here, the industrial cold installation is necessary for the preparation of precooked fresh dishes and is used in different configurations: the food production area at 6-8 °C, whereas the delivery area is to be maintained at 10-12 °C. HyCool is poised to make a big difference in solar heat use in European industry, and so will the EU-funded SHIP2FAIR project, essentially HyCool’s ‘twin’ project that is due to finish in March 2022. Their developments focus in particular on the heating needs of the food and agro industry and are being demonstrated and validated in a variety of processes including spirits distillation (Martini & Rossi), meat transformation (Larnaudie), sugar boiling (RAR group) and wine fermentation and stabilisation (RODA). The objective is to supply 40 % of the heat demand through solar power.
Keywords
HyCool, solar heat, industrial processes, cooling, CSP, heating, concentrated solar power, hybrid heat pump
