The national grid pumps electricity into our houses at 230 volts, Alternating Current.
If you are being greedy and have high power demand – using an array of hairdryers to heat your living room let’s say, or running a network of underground marijuana farms with all their heating, lighting and irrigation needs… then you might need an extra two phases of electricity which all comes in at a slightly less handy but much more lethal 415 volts.
Over bigger distances the voltage has to be massively bigged up. Without higher voltages the power seeps out the cabling like water out of a leaky pipe.
How it does this I am not completely clear but the analogy to electricity being just like water must be part of the answer.
Power stations in the UK create the unseen jesus-magic of electricity at 25,000 volts which then gets ‘stepped up’ to 400,000 volts to transmit along the biggest cables of the National Grid. Once this gets to a town this has to be taken back down to lower voltages at sub stations and then on down to your premises.
Across London there are a grid of these substations, sometimes in purpose built sites;
the building most of you think is probably a huge steel toilet in Elephant and Castle is one of these.
The majority were existing buildings that were converted for use.
At first glance they are fairly anonymous, bland buildings, but they are modified fortresses – not surprising their importance and fairly significant Danger of Death potential.
What I like about them is how cleverly they are hidden away until you stop to look carefully and see the full razor wire bizarreness of them. There is one I pass on my way to work everyday that I took some photos of:
Then I started looking out for a few more. One just of Bond Street:
And another very close to where I live:
They are expensive and problematic to replace and so built to last. Many of the building were bought up and converted in the fifties and sixties and so they have a faded, nuclear bunker charm to them. Mid Cent Mod for engineers.