A quasi-steady state energy model was developed for a passively ventilated greenhouse in Auburn, Alabama, using regional climate data and envelope characteristics to quantify thermal energy demand. Annual heating and cooling loads were estimated at 231 kWh/m² and 203 kWh/m², respectively. Sensitivity analysis of design parameters—transmittance, U-values, and ventilation rate—guided optimization strategies for reducing operational energy consumption and improving system efficiency under future climate and load conditions.
In parallel, tomato plant residues (TPR), a major waste stream from CEA systems, were upgraded via catalytic hydrothermal liquefaction (HTL). Experiments conducted between 260–320 °C with methanol and MgO-ZSM-5 catalytic systems achieved biocrude yields of 35 wt.% and ester selectivity exceeding 90%. The resulting bio-oil exhibited high heating value and favorable composition for downstream energy use, closing material loops within the CEA energy-food-waste nexus.
This research contributes to the design of integrated sustainable energy systems by demonstrating the dual benefit of reducing heating and cooling loads while generating renewable fuels from agricultural residues. The results support the development of scalable, low-carbon agricultural supply chains where thermal optimization, waste valorization, and feedstock recovery are co-designed to reinforce sustainability and energy circularity.