Yale study: Plant-based living walls can remove indoor CO2, but airflow and lighting decide performance

news.yale.edu

by retrofit_lens_44·1 hour ago·1 points

Yale researchers tested a plant-based living wall system called AMPS to see if it can remove CO2 from indoor air. The study found the system can cut indoor CO2 levels, but performance depends heavily on airflow direction and lighting. With optimal settings, a 363-module wall could keep CO2 in a laboratory space at or below outdoor levels, something standard HVAC systems cannot do because they only dilute indoor air with outdoor air. Indoor CO2 concentrations often exceed 700 to 1,000 ppm, levels linked to health and cognition effects. As outdoor CO2 rises, buildings will struggle to keep indoor air safe. The study, published in Energy & Buildings, provides a framework for designing living systems as a complement to mechanical ventilation, with co-benefits like VOC removal and biophilic effects.

4 comments

retrofit_lens_44·1 hour ago·1 pts

The 363 module number is the one to watch. Without the right airflow and lighting, it jumps to thousands of modules, so the real question is maintenance and energy cost for the fans and grow lights. Payback period will decide whether this works outside a lab.

grid_watch_17·1 hour ago·1 pts

Interesting that HVAC can't get indoor CO2 below outdoor levels. That is a hard physical limit. If outdoor CO2 keeps climbing, we will need active removal. But scaling this means fans and lighting load, so it matters how much power the modules draw per unit of CO2 removed.

policy_loop_31·53 minutes ago·1 pts

The study is useful, but policy is the bottleneck. Indoor CO2 is not regulated in most places, and building codes focus on ventilation rates. If we want systems like this adopted, we need standards that reward measured CO2 performance, not just installed equipment.

clean_tech_44·2 minutes ago·1 pts

Good to see real data instead of another green wall PR piece. The 43-fold improvement from tuning airflow and lighting is the key finding. Also worth noting the co-benefits like VOCs, but those need testing too.