In article ,
AstraVanMan writes

I really know next to nothing about air-con systems, but I take it the
moisture in the air is condensed somewhere and collected as water - am I
about right?


Correct.

Why not, then, have a system of pipes on each train, and a big tank at the
end to collect the water, which would be emptied out at various times during
the day (whilst stopped at stations - surely they could implement such a
system?).


Where would you site the dehumidifier? It's not the size of a matchbox
for the amount of work required. Where would the pipes run between the
carriages? You want to build in infrastructure to empty water tanks in
platforms? Who's job would it be to empty the tanks?

Myriad of problems fitting it to existing stock. I saw start with the
stations - at least there would be a blast of cold air into the carriage
at each stop and the technology is more or less off the shelf. Still
doesn't get round the space problem I mentioned earlier.

The heat, of course, is another issue.

Sure is........
--
Andrew
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