When planning future underground systems and sub systems a strategic approach is
There must be co-existence with other systems and a serious system approach needs to adopted.
Environmentally responsible approaches are the
only ones to be considered.
The deep tunnels are becoming Cavern
Thermal Stores. Over the years, there has been a steady build-up of heat in the ground surrounding the tunnels.
We have suddenly discovered that the London Underground deep tunnels is
becoming a massive UTES system. It should be possible to reverse the situation and start taking advantage of the large number of potential storage areas.
The summertime overheating on the Underground Transportation System or
"The Tube" as Londoners know it as is not going to go away, we may be lucky and
have a temporary reversal in the Global Warming trend but make no mistake the
trend is up.
The demand for increased capacity is very much an upward trend.
Energy costs will increase in the foreseeable future
The highest priority is to cool the tunnels, it is tempting to look at the
concourses, platforms and public areas within the station, however only in exceptional
circumstances should the initial effort be applied elsewhere.
It is incumbent upon us to recycle and utilise the thermal energy developed
A first step would be to halt the unnecessary generation of heat within the
Where heat from stations and equipment rooms is entering
the tunnels, dump it somewhere else for the time being then work out ways of
More efficient trains equipped with regenerative braking.
see Grisman. As far as possible reduce the mass of the trains.
Improving the existing ventilation systems and other passive systems, for example the intelligent use of dampers to introduce cooler, or cooled air at the mid-points and to use the piston effect of the trains within tunnels to carry the cooled air towards the stations where it displaces the heated air which will tend to vent using the station pedestrian entry routes.
UTES or interseasonal storage technology is an excellent match to the problem of cooling London Underground. Good fortune has provided opportunities in the shape of an abundance of unused tunnels and voids that lend themselves to roles as
cavern stores. Simply applying tunnel air-cooling derived from winter temperature air to the deep tunnels and communicating tunnels and caverns will
provide stored coolth which can be used to halt and reverse the root cause of the problem, and into the bargain,
create opportunities to store usable energy.
Finally, a significant
proportion of the Terawat-hours plus used every year to power
London's underground rail system has become heat energy stored in the
ground in the proximity of the deeper tunnels. There is a question about ownership of
this vast store of energy. Will it benefit the people who have paid for it (Mainly London's residents) - through cheaper
heating, or will it be allowed to go to waste.