Design and evaluation of climate-adaptive greenhouses for semi-arid regions using CFD model

International audience Greenhouse systems play a critical role in sustaining crop production in arid and semi-arid regions, where open-field agriculture is constrained by harsh climatic conditions and chronic water scarcity. In the southern Mediterranean basin, particularly in Morocco, traditional greenhouses, such as the widely adopted Canarian-type greenhouse, are increasingly challenged by rising temperatures and growing climate variability stressing the need for climate-resilient designs tailored to local conditions. This study presents a systematic evaluation of eight greenhouse shapes integrated into five structural configurations: Canarian (even span), single slope (types A and B), uneven span, slant-leg, Mansard, modified Quonset, and modified Gothic arch. The thermal performance, airflow dynamics, and resource efficiency of each configuration are evaluated using a combination of Computational Fluid Dynamics (CFD) simulations and on-site experimental validation. Based on the insights gained, an innovative design, the Multi-level Ridge greenhouse, was developed, incorporating the most effective geometric and ventilation features identified across the earlier evaluation. This new structure demonstrated superior performance, maintaining internal temperatures up to 7 K lower, enhancing diurnal airflow patterns, and achieving more stable relative humidity levels. Its optimized roof geometry, strategic opening location, and multi-span design significantly improved natural ventilation and passive cooling. The Multi-level Ridge configuration resulted in annual energy savings exceeding 145,000 kWh, along with notable reductions in operational costs and greenhouse gas emissions. A comprehensive 3E (energy, environmental, and economic) analysis confirmed its potential as a scalable, sustainable solution tailored to the climatic challenges of semi-arid regions, providing a practical and robust alternative for future greenhouse development in Morocco and similar environments.