
London's Crossrail will generate electricity using drafts created by trains - rbanffy
http://www.wired.co.uk/article/city-wind-farms-energy-crossrail-london-renewable-energy?utm_content=buffer5dc2f&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer
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gus_massa
I don't understand completely. They want to put some device to harvest the
wind caused by the trains? Is the sheet parallel or perpendicular to the
surface?

IIUC this will decrease the speed of the wind around the train, and it will
probably increase the drag on the trains. Fluid dynamics is too complex and
sometimes you get unexpected results. Have they run a simulation? Is the money
get from the electricity harvested by the device greater than the cost of the
additional draft?

Anyway, at least here in Argentina the walls of the subways tunnels are not
super smooth, so perhaps something attached to the wall would not change the
current situation.

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opless
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?

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jjgreen
While New York's subways may have drafts, the London Crossrail will have
draughts :-)

