Offering reserve capacity to renewable-rich power systems can cut plant factory energy costs by up to 87 %

Controlled environment agriculture (CEA) provides a sustainable solution for food production, but high energy costs hinder its widespread adoption. Using commercial Plant Factories with Artificial Lighting (PFALs) as an example, we demonstrate that selling reserve capacity to renewable-rich power systems, i.e., by committing to decrease (up-reserve) or increase (down-reserve) electricity consumption from flexible electrical devices, can significantly reduce energy costs while maintaining optimal food production climates. Results indicate a cost reduction of up to 87 % per kilogram of food produced, with an average reduction of 82 % across cities. Up-reserve is primarily achieved by reducing consumption for heating or cooling, while down-reserve is supplied by increasing lighting consumption. PFALs with smaller electrical device capacities benefit more from the proposed model. The relative cost reduction per m2 doubles when the capacities are quartered. In addition to analyzing cost reduction, we also examine electricity consumption and the associated carbon emissions. Compared to the benchmark, the new economic model can lead to lower emissions when providing up-reserve or when no reserve is activated. However, in the case of down-reserve provision, achieving lower emissions depends on the relative carbon emission intensity. Our findings improve the cost competitiveness of PFALs and suggest a promising economic transition for CEA with flexible electricity use.