Charlotte, in this house we obey the laws of thermodynamics! Seriously though, It's unlikely to be powered by 'trains' but the thermal differences between tunn

Charlotte, in this house we obey the laws of thermodynamics! Seriously though, It's unlikely to be powered by 'trains' but the thermal differences between tunnel endpoints causing the airflow. Sure there's airflow that's generated by trains but harvesting that doesn't seem to make sense as the air needs to be moved out of the path of the train so would end up as a net loss if significant energy was recaptured?