From Wikipedia, “When the tunnels were built the clay temperature was around 14 °C; this has now risen to 19–26 °C”
According to the same page though, the tunnels only add 4% to the heat and humans add 7% — remaining 89% comes from the trains; unless I misunderstood something.
According to the same page though, the tunnels only add 4% to the heat and humans add 7% — remaining 89% comes from the trains; unless I misunderstood something.
https://en.m.wikipedia.org/wiki/London_Underground_cooling