Jorge Gutierrez, a retired naval engineer, calls the 15-foot high (5 meters) box-like steel contraptions he helped design a "super tree" and says each one can convert as much carbon dioxide into oxygen as 1,200 trees.
In Peru, which is hosting the United Nations climate change talks Dec. 1-12, the vast majority of electricity is generated from hydropower and natural gas, both relatively clean sources of energy. But exhaust-spewing buses and cars fill the city's air with throat-rasping fumes.
"The secret is to reproduce what nature does for free to clean the air," Gutierrez said.
The machines, which each cost $100,000 to build but just $6 a day to run, suck in the dirty air and trap contaminants in water. Residual solids are eventually packed into secure containers that can be deposited at a landfill.
Although the purifiers run on electricity, Gutierrez said the greenhouse gas emissions they produce are only a fraction of what they can remove. And they would quickly pay for themselves through advertising revenues, the creator said.
They also offer passers-by the rare chance to breathe "pure air," which is pumped into attached walk-in booths. A machine installed in front of a hospital in Lima's Jesus Maria district advertised "free, clean air here" and drew confused stares.
So far, only two machines are up and running, financed by local businesses and charities. Gutierrez said some 400 would be needed to push back pollution levels in Lima, home to 10 million people and swarms of unregulated buses.