100,000 please Mr Livingstone

I’m going to be rich! Apparently there’s a reward for the design of a cooling system for London’s tube network:

…Subterranean heat reached 52 degrees Celsius [on the tube], with humidity factored in. Ken Livingstone, London’s mayor, has promised a reward of £100,000 ($160,000) to anyone who invents an air-conditioning system that will work on the trains.
From the Economist London Briefing, August 2003

So, without further ado, I give you the solution. Mr Livingstone, you can contact me by clicking here and removing the spamtrap – I’ll give you an address to send the cheque. Behold:

plans for the ultimate tube air conditioning: cash please Mr Mayor

And that, I’m sure you’ll all agree, is that.