Nanoplastic and bio-mulch passively cool greenhouses

Described in the journal Nexus, the dual system uses a combination of a nanoplastic greenhouse covering and biodegradable mulch to significantly reduce heat. According to the study, the KAUST team was able to lower temperatures of miniature greenhouses by 25°C and increase crop yields of Chinese cabbage by nearly 200 per cent.

To create the covering, polyethylene was infused with nanoparticles of caesium tungsten oxide. These molecules absorb heat-carrying infrared light while still allowing the visible light that drives photosynthesis to pass through. 

"Most greenhouse covers, whether they are made of glass, polycarbonate or polyethylene, transmit more than 90 per cent of light, including infrared light, which has no benefit to crop yield but generates heat,” said KAUST Professor Qiaoqiang Gan, an expert in passive cooling systems who developed the nanoplastic.

“Our goal was to create a cover that lets good light in and keeps bad light out.”