This blog was written by volunteer Reece Richards.
In my present job, I’ve been supporting work that is connected to the National Grid upgrade. Subsequently I’ve become slightly obsessed with the story behind our electricity network. Our electricity grid is easy to take for granted, but the more I’ve learnt, the more I find beauty in the system (despite the arguably ominous towers). The grid is a piece of national infrastructure to be truly proud of, a significant venture that helped lead the charge in global electrification.
So, to best understand where we’re going next on our electrification revolutionary path, it helps to know just how far we’ve already come.
To appreciate the scale of the Great Grid Upgrade please picture Britain in the 1920s.
The country is coming out of the First World War, industrial dominance is starting to wane, and times are bleak. Electricity wasn’t a given, it was a luxury. Supply was a patchwork of private companies and local councils, which made power expensive and inefficient. For many households, keeping just five light bulbs on for one day could cost a week’s wages! Clearly, something had to change.
1926: The birth of a national network
What’s that…. did somebody say nationalised electricity? Well, not quite.
In 1926, Conservative Prime Minister Stanley Baldwin introduced the Electricity Supply Act. This didn’t nationalise power stations, but it did something revolutionary, it created a coordinated national electricity system. Over 4,000 miles of transmission lines and cables were built across Britain, linking the 122 most efficient power stations into a single network. It was a huge success, and by the start of the Second World War around two-thirds of British homes had access to electricity.
This was the foundations of the ambitious National Grid! Even the infrastructure reflected the era’s determination. The steel transmission towers were designed by architect Sir Reginald Blomfield, who took inspiration from ancient Egypt.
It’s worth keeping in mind the early grid was designed for a fossil‑fuelled world and large, centralised power stations.
1950s–1960s: Enter the ‘Supergrid’
By 1950, a new problem emerged; the original 132 kV grid was already reaching its limits. It simply hadn’t been designed to move electricity in bulk over long distances, and demand had increased around nine‑fold since the grid was first built. This was the age of the electric iron, black‑and‑white televisions, radios and electric cooking. A few boffin engineers also calculated it was now cheaper to transmit electricity than to keep transporting coal by rail. It was almost like they had unearthed a superpower, a Supergrid if you will?
To deliver the Supergrid, the British Electricity Authority committed £52 million (roughly £1.4billion in today’s money) over ten years to build more than 1,150 miles of new 275kV transmission lines.
This increased voltage step change was only possible due to the advancements in insulator technology from the late 1930s. Then by the 1950s, engineers could more than double transmission voltage to 275 kV, moving power efficiently over much longer distances. Within a decade they pushed further again, introducing 400 kV transmission. This is the level that still underpins the grid today!
Many of the transmission routes established during this period remain operational now, continuing to transmit power reliably on towers erected over seventy years ago.
Bigger kit, bigger challenges; substations and logistics
The Supergrid wasn’t just about overhead lines, the power needed substations and equipment on an entirely new scale. Post-war Britain’s engineers and manufacturers were stretched, so substation designs were standardised to speed up delivery. By 1960, around 60 transformers had been installed across the network, often weighing more than 150 tonnes and standing as tall as a London bus!
Even back in those days, one challenge stood out, not electrical performance, but road logistics. Transporting equipment of such size across Britain’s roads is a complex challenge that persists today.
1980s–2000s: Privatisation, markets and a centralised system
The architecture of the electricity network is ultimately governed by the generation mix feeding into it.
In Thatcher‑era Britain, the Central Electricity Generating Board was broken up and the National Grid Company was created to own and operate the high‑voltage transmission network. That company was later sold to private investors, completing the privatisation of electricity transmission. The result is the system we recognise today; regional distribution network operators and National Grid plc (listed on the London and New York stock exchanges).
By the turn of the millennium, the context started to shift again. The digital age began driving demand, and concerns around greenhouse gas emissions grew. However, at the same time, the UK’s ‘dash for gas’ (enabled by North Sea reserves and flexible cheap gas turbines) saw privatisation reinforce a highly centralised electricity system. For a while, that model was the status quo.
2010s onwards: Rise of the Renewables and the outdated grid
Finally renewable energy gained real momentum due not just to environmental factors but also supply chain cost reductions and sovereign energy security draws.
This is where our modern challenge appears. Much of the existing infrastructure wasn’t designed or upgraded for renewable generation. Wind, tidal and solar are geographically dependent. Our strongest resources aren’t always where electricity demand is highest (take Scotland’s wind resource for example). The places that use the most power are rarely the places that can generate the most renewable energy.
So a grid that has served us reliably for decades, now starts to feel a bit like only using the Bakerloo, Metropolitan and Central line to meet London’s current transport needs. What we really need is the electricity equivalent of the Elizabeth line – an upgrade that utilises windy coasts, tidal ranges and even famously elusive English sunshine.
That’s where the Great Grid Upgrade brings us to now.
Future community energy connections
For community energy groups, this is more than just a big national engineering project, the upgrades shape what may be possible locally. Recent announcements from National Grid aim to provide smarter and fairer grid connections for community energy groups at lower costs. Geoprint for Energy Club Connections and Operations (GECCO) seeks to unlock long-term benefits for communities by creating a connection that’s exclusively available for community energy groups, enabling local balancing and lower bills.
Furthermore, recent legislation, in response to the fuel crisis in the middle east, announced by the government aims to facilitate plug-in solar for small homes. Commonly found on apartment balconies, plug-in solar systems are small, lightweight DIY solar kits that allow you to generate electricity and offset your daytime energy bills by plugging directly into a standard 13-amp UK wall socket! Our German counterparts have been leading the way when it comes to plug-in-solar, having installed more than one million systems between 2022 and 2025! We may one day soon see our very own high rises of Croydopolis with plug in solar panels hung off resident’s balconies.
If the last 100 years of the electricity grid advancements can teach us anything, it’s that the network changes when the population habits changes. As the country pushes towards net zero, doing our best efforts to curtail the effects of climate change, this latest iteration of the National Grid overhaul is the next big chapter in Britain’s electrification story. Big ambitions birthed the National Grid and now securing clean local power for generations to come is the modern equivalent of Baldwin’s ideology.
