Solar-powered greenhouse heating with gravity storage: A techno-economic and environmental perspective

As global efforts to decarbonize agriculture intensify, the need for integrated renewable energy and storage systems in greenhouse operations has become increasingly urgent. This study investigates the technical, environmental, and economic feasibility of a hybrid system combining photovoltaic (PV) electricity generation with a shaft-based Gravity Energy Storage System (GESS) for greenhouse heating. The proposed system is applied to the Zonguldak region of Türkiye, where decommissioned mining shafts offer a unique opportunity to repurpose post-industrial infrastructure for long-duration energy storage. An optimization model is developed to determine the optimal capacities of PV and GESS under different investment scenarios. The model outputs are then evaluated through a comprehensive life cycle assessment (LCA) and financial analysis, including Levelized Cost of Storage (LCOS), Net Present Value (NPV), and Internal Rate of Return (IRR). Results reveal that the integrated PV-GESS system significantly reduces dependency on grid electricity while maintaining low greenhouse gas emissions and fine particulate matter formation. Notably, GESS demonstrates a much lower environmental impact per discharged kilowatt-hour compared to conventional battery technologies. The findings highlight the potential of mechanical storage systems in agricultural decarbonization and demonstrate how underutilized infrastructure can be transformed into climate-friendly assets. By providing a replicable framework that merges energy system design, environmental accounting, and economic viability, this study offers valuable insights for policymakers, researchers, and energy planners aiming to promote low-carbon, resilient food production systems.