Decarbonizing desert greenhouse crop production with direct air capture–based CO2 enrichment

High-tech greenhouses in hot-desert climates deliver high yields with minimal water and land footprint but are constrained by costly, emissions-intensive carbon dioxide (CO₂) enrichment supplied via trucked liquid-CO₂. We evaluate two adsorption-based direct air capture (DAC) systems—temperature-vacuum-swing (TVSA) and moisture-swing (MSA)—as on-site enrichment alternatives, benchmarking against conventional liquid-CO₂ supply. Using integrated techno-economic and life-cycle assessment models, we show that DAC systems achieve comparable levelized costs and lower climate-change burdens for high-tech greenhouse cherry tomato and lettuce crop production systems by avoiding transport-related emissions. Sensitivity analysis identifies electricity price and carbon intensity as well as sorbent productivity as dominant performance drivers. In solar-abundant desert regions, powering high-tech greenhouses—including DAC-based CO₂ enrichment systems—with low-cost, low-carbon photovoltaic electricity alleviates both cost and emissions burdens. Results show that adsorption-based DAC systems can provide cost-competitive CO₂ enrichment and reduce associated greenhouse-gas emissions relative to trucked liquid CO₂ when powered by low-carbon electricity, indicating that DAC-E can support more sustainable greenhouse production in hot-desert regions.