Evaluation of Technical Feasibility of Solar Heat Integration in Agri-Food Industries

This work assesses the use of different solar heating integration configurations and heating storage solutions for three different agri-food industries located in southern Europe. TRNSYS is employed to model different Solar Heat for Industrial Process (SHIP) integration options and to quantify the solar thermal share with respect to the overall thermal demand, as well as to estimate the avoided consumption of fuels and CO2 emissions in the existing boiler units as a result of the solar system integration. The SHIP integration is complemented with the evaluation of selected phase-change materials (PCM) to promote latent heat storage under the specific conditions of the considered agri-food demo sites and solar irradiation characteristics. The arrangement of flat-plate solar collectors coupled with latent heat storage was found to enhance the yearly averaged solar share of the SHIP solutions, reaching 13% of the overall thermal demand for an average Spanish winery demo site. Furthermore, the estimation of the gross solar heat production for a mid-size Italian spirits distillery yielded 400 MWh/y, leading to annual fossil fuel savings of 32 tons and yearly avoided CO2 emissions of up to 100 tons. Similarly, the SHIP integration model for an average French charcuterie predicted a 55% solar share of the thermal demand required for plant cleaning purposes, resulting in roughly 50 tons of CO2 emissions avoided per year. The estimated payback period (PBP) for the Italian spirits demo case under the current economic scenario is below 9 years, whereas the PBP for the other demos does not exceed the expected lifetime of the solar plants (25 years).