Here, below London, 32km of new tunnels are nearly finished.
But these aren't for people: they're for power.
Cables carrying 400,000 volts will run through here,
supporting the city as it keeps growing
and keeps demanding more and more electricity.
This project cost a billion pounds,
all to keep the lights on.
So how did we get to this?
Back in the 1920s, electricity was generated by hundreds of small companies
in towns and cities across the country.
They were all different and mostly incompatible:
London alone had 24 voltages and 10 frequencies.
So if you moved to the next street over,
you might have to replace all your light bulbs.
If you had any light bulbs, that is:
the cost of electricity was out of reach of nearly everyone.
Now the answer might have been to do what other countries in Europe were doing:
set up and enforce standards, regulate prices,
maybe even nationalise the power companies.
And bring the price down for everyone --
people and business. Good plan in theory,
but the trouble was that the Prime Minister at the time was Stanley Baldwin,
and he led the Conservative party. Politically,
he couldn't just assume control of private corporations!
That was socialist.
That was something that the Other Side did.
So the solution was a very clever and very British compromise:
the National Gridiron, later just National Grid.
The Central Electricity Board,
backed up by the government and run privately,
would construct and own the central infrastructure.
It would build a network of transmission lines sweeping across the country.
The Grid would reduce the risk for the private generating companies
and let them reach a much, much, larger market.
If they wanted to connect and reach everyone,
they had to meet the Grid's standards for frequency,
for voltage, and for reliability.
The greatest story I found while I was researching this is that
originally, there were six separate grid areas
spread all around the country, all run individually.
It was judged too risky by their managers
to actually connect them all into one National Grid.
But it was theoretically possible.
Sometimes two or maybe even three of those grid areas were connected
to help out if one power station somewhere went down.
So on the night of 29th October, 1937, without any permission,
the engineers in the control rooms quietly decided
to connect the whole country together for an hour or two
and see what would happen.
And it worked. And a year later,
even their managers agreed: it was the only way
to make sure the lights stayed on everywhere.
And so while the level of regulation,
and the level of privatisation,
has changed over the years --
as it has in pretty much every country in the world --
and while the technology has developed to the point
that instead of laying transmission lines,
we are now in billion-pound tunnelling projects 60m under London,
that mostly-private grid is what we still have today.
It's listed on the London Stock Exchange.
If history had turned out differently,
perhaps this tunnel would have been a government operation:
but even if it was,
we'd have still needed this to keep the lights on.
Thank you very much to the National Grid
and all the folks who've helped bring me down to the Power Tunnels,
along with Geoff from Londonist,
who's done a video about these tunnels themselves
and all the infrastructure around me.
Go check that out on his channel!
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