Carbon capture trains which suck up emissions as they go could carry the rail industry to net-zero, while also helping to battle wider climate change.
Engineers from the University of Sheffield have joined forces with the US-based CO2Rail Company to design air-cleaning wagons that can be easily slotted into existing trains.
Not only would they cut the environmental damage from traditional railway engines, but they would have extra capacity to pull carbon dioxide directly out of the air, bringing meaningful reductions in atmospheric CO2.
“Imagine stepping on to a train each morning, seeing the CO2Rail cars attached, and knowing that your commute to work each day is actually helping to mitigate climate change,” said Eric Bachman of the CO2Rail Company.
Current static carbon capture systems need energy-intensive fans to move polluted air into collection chambers, but the new rail cars take advantage of the slipstream of moving air generated as a train travels down a track.
The fumes are filtered into a large cylindrical collection chamber where they move through a chemical process which separates the carbon dioxide from the air, returning clean air back into the atmosphere.
The harvested CO2 is collected, concentrated, and stored in a liquid reservoir until it can be emptied and transported into the circular carbon economy, where it could, for example, be pumped into greenhouses to help plant growth.
To make the process even more efficient, the carbon capture carriages are powered using energy generated when trains brake and decelerate, which is currently vented as heat.