Optimal control of Chinese solar greenhouse cultivation

The benefits of introducing heating, CO2 supply, ventilation and LED lighting in a Chinese solar greenhouse are investigated. To that end, a two time-scale receding horizon optimal control system is assumed to accompany the introduction. The model of the Chinese solar greenhouse dynamics used by the optimal control system incorporates the effect of a north wall, present in any Chinese solar greenhouse. This wall stores heat during the day and releases heat at night to improve temperature. The optimal control system also takes control of a thermal blanket, that can be partly opened and closed to reduce heat loss to the environment. Apart from performing real-time optimal control, the optimal control system enables computation of improvements in terms of profit. Finally the feasibility of real-time implementation of the two time-scale receding horizon optimal control system on a personal computer is verified. •Application and economic performance of CSG's can be greatly enhanced.•Optimal control of a CSG can be done from a single PC.•LED lighting adds significant economic performance to lettuce cultivation.