Optimization of Greenhouse Microclimate Parameters Considering the Impact of CO2 and Light

Abstract

The most critical parameters of the microclimate in greenhouses are air and soil temperature, air and soil moisture, plant illumination, and carbon dioxide (CO2) concentration in photosynthesis. New energy sources and resource-efficient management of microclimate parameters in greenhouses can be utilized to reduce greenhouse crop cultivation costs and increase profits. As the plant mass increase depends on photosynthesis, which involves the formation of glucose in the plant chloroplasts from water and carbon dioxide under the influence of light radiation, the saturation of greenhouses with carbon dioxide has become popular in recent decades. However, insufficient light slows down the process of glucose formation, while excessive light intensity negatively affects photosynthesis. Based on the experimentally proven Van Henten model of plant growth and using the MATLAB environment, a methodology was proposed, and the dependence between CO2 concentration and leaf lettuce illumination power required for maximum photosynthesis was determined. It is equal to 0.57 ppm/(W/m2). Such dependence should be considered when designing control systems to reduce resource and energy costs for greenhouse crop cultivation while ensuring maximum yield.

Spatial, Temporal, and Vertical Variability of Ambient Environmental Conditions in Chinese Solar Greenhouses during Winter

“…CO2 levels in ambient air are typically about 340 ppm by volume, and all plants grow well at this level [46]. However, when CO2 levels are increased by 1000 ppm, photosynthesis rises correspondingly, resulting in an increase in available sugars and carbohydrates for plant development [47] and inducing a favorable effect on crop yield [48]. According to Figure 11, the CSG with crops demonstrated optimal growing conditions between 600 and 1000 ppm CO2.…”

Energy Design and Optimization of Greenhouse by Natural Convection

“…Studies on the heterogeneous microclimate in typical greenhouses in Central China [15], the development of microclimate models for predicting temperatures in naturally ventilated greenhouses [16], and the formulation and validation of mathematical models of greenhouse microclimates [17] are crucial for our approach. The exploration of greenhouse environment modeling and simulation for microclimate control by [18,19], as well as the works on microclimate conditions in naturally ventilated greenhouses [20], and the optimization of greenhouse microclimate parameters [21] considering the impact of CO 2 and light, make significant contributions.…”