Seasonal energy storage for greenhouse production

F. de Ridder, J. van Roy, B. de Schutter, W. Mazairac
This paper presents a study of seasonal thermal energy storage in the glasshouse horticulture industry. Nowadays, many greenhouses in northwestern Europe are equipped with combined heat and power plants and gas boilers to generate heat, power for lighting and carbon dioxide as a fertilizer. These three drivers do not allow much flexibility to profit from opportunities on the energy spot market. Recently, large seasonal storage devices have become commercially available (e.g., Ecovat systems). In this study, their impact on the operational costs and the carbon dioxide emission was examined. A real-world case study was used, where data of nine greenhouses and 21 CHP's were incorporated. The novelty of this research was that seasonal heat storage in the greenhouse horticulture industry was quantified. Therefore, a simulation, based on a control problem was performed. This allowed us to make comparisons between different situations. We determined that heating costs can be reduced by 0.50 to 6.15 € m‑2 year‑1 and carbon dioxide emissions by 700 g m‑2 year‑1. Next, sensitivity analyses were performed. We concluded that i) the optimal energy storage size is approximately 550 m3 ha‑1 or 50.000 m3 for this case study; ii) insulation properties of the storage device may in reality differ from design values. Therefore, the sensitivity of cost reduction with respect to insolation is examined, but this is not a critical parameter, and iii) carbon capture techniques have a modest impact on the operational costs 
(-0.03 € m‑2 year‑1).
de Ridder, F., van Roy, J., de Schutter, B. and Mazairac, W. (2020). Seasonal energy storage for greenhouse production. Acta Hortic. 1296, 747-752
DOI: 10.17660/ActaHortic.2020.1296.94
greenhouse horticulture, combined heat and power, thermal storage, Ecovat

Acta Horticulturae