Toyota building an engine that cleans the air as it drives
The company is working on an engine that filters the CO2 out from the air around it, but there’s a catch, as Nile Bijoux explains.
Toyota is developing an engine that cleans the air as it runs, but it won’t be in production cars any time soon. First prototypes of the ‘carbon capture’ system are being tested in a GR Corolla race car, and initial results are good. Toyota says the air coming out of the back of the Corolla contains less carbon dioxide (CO2) than the air around it.
The system comprises a pair of filters mounted just before the intake manifold made from a ceramic catalyst and coated in a CO2 absorbent developed by Kawasaki. Air passes through the filters which catch the CO2 and send it to a recovery fluid.
One property of Kawasaki’s absorbent is that it releases CO2 when exposed to temperatures above 60C, which means that heat from the engine oil causes the CO2 to separate.
The CO2 released is passed through the recovery fluid, bubbling away as it dissolves.
“Typically, facilities for capturing CO2 from the atmosphere use fans to suck in air and heat to detach the CO2, all of which requires energy,” said Naoaki Ito, GR Vehicle Development Division project general manager.
“The key point about the H2 Corolla’s system is that it uses the existing air intake and heat within the engine.”
But there’s a catch. If the mention of a GR Corolla race car rang any bells, that’s because it’s the same one in which Toyota put a liquid hydrogen-powered threecylinder engine, which emits far less CO2 than regular petrol.
Toyota admitted there is still room for improvement, with the amount of CO2 currently able to be captured limited to 20 grams over 20 laps of Fuji Speedway (4.563 km per lap), and the filters must be replaced by hand at every pitstop.
But that’s why it’s a prototype. Toyota and Kawasaki are working to increase capture capacity and reduce the amount of human interaction needed.