The Nuclear Power Station
Before talking about the substation itself, we should mention Bradwell nuclear power station which it was constructed alongside to serve. The nuclear power station began construction back in 1957 on the edge of the site of RAF Bradwell Bay when nuclear power was emerging as a viable option. It is of Magnox design, referring to a nuclear process using graphite-moderated uranium with carbon dioxide as coolant. Non-oxidising magnesium- aluminium alloy is used to clad the fuel rods, where the process gets its name. The process was first created to produce both general electrical power, as well as plutonium-239 used in nuclear weapons. The power station was constructed by several companies, including A. Reyrolle & Co. who we saw the name of branded on many of the substation components. The power station was complete and started generating in 1962. It had two reactors of 300MW output, although this was reduced to 242MW after discovering that some components were oxidising inside the reactor. Nine turbines and twelve gas circulators were supplied by C. A. Parsons & Co at the turbine hall beside to the reactors, comprising six 52MW main turbines supplying additional power, and three auxiliary 22.5MW turbines (one for each reactor's CO2 circulators, and one standby). The power station provided an enormous amount of electricity capable of powering Essex's larger towns in a single day.
Before talking about the substation itself, we should mention Bradwell nuclear power station which it was constructed alongside to serve. The nuclear power station began construction back in 1957 on the edge of the site of RAF Bradwell Bay when nuclear power was emerging as a viable option. It is of Magnox design, referring to a nuclear process using graphite-moderated uranium with carbon dioxide as coolant. Non-oxidising magnesium- aluminium alloy is used to clad the fuel rods, where the process gets its name. The process was first created to produce both general electrical power, as well as plutonium-239 used in nuclear weapons. The power station was constructed by several companies, including A. Reyrolle & Co. who we saw the name of branded on many of the substation components. The power station was complete and started generating in 1962. It had two reactors of 300MW output, although this was reduced to 242MW after discovering that some components were oxidising inside the reactor. Nine turbines and twelve gas circulators were supplied by C. A. Parsons & Co at the turbine hall beside to the reactors, comprising six 52MW main turbines supplying additional power, and three auxiliary 22.5MW turbines (one for each reactor's CO2 circulators, and one standby). The power station provided an enormous amount of electricity capable of powering Essex's larger towns in a single day.
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The nuclear reactors in 1963. The turbine hall, now demolished is behind. A similar view of the cladded reactors in 2021, reminiscent of the Chernobyl sarcophagus.
In 1969, the power station had a new computer installed to monitor the temperature of its reactors; the Honeywell 316. Whilst this resembles somewhat of a joke by modern standards, it was still in use until 2000 when it finally packed up. In 1999, it was announced that the power station's planned obsolescence would mean it would stop generating by 2002. This made it the first nuclear power station with a planned closure in the UK. All spent fuel was removed by 2005, with the turbine hall demolished in 2011 and underground waste storage vaults (hmm) emptied by 2016. Final demolition was complete by 2019, with the two reactors having been cladded inside 34,000 square metres of weatherproof aluminium sheeting to allow for radiation to finally decay. The buildings have been locked until 2083 when final clearance is planned, quite fascinating really. The date scheduled for completion of full dismantling is 2104. Despite all that effort, China wants to build a 2,200MW Bradwell B nuclear power station next door.
The 132kV Substation
In contrast to the power station, there's not a whole lot to say about the substation itself. It can be presumed that the substation was constructed at the same time as the power station, and served the purpose of receiving the freshly-generated electricity from the reactor and transforming it for delivery across the National Grid's powerlines, still visible at the back of the substation. The electricity would then be sent to Rayleigh Main Substation, still in use today and visible from the A130, which then distributed the electricity locally around Essex. It apparently was designed for 275kV before being scaled down to 132kV, perhaps like the power station's output. At the centre of the transformers and plinths is a rectangular brick control building, where the substations controls and monitoring equipment is. Whilst the building appears plain on the outside, it still has some architectural flair.
Several 1960s' British Pathe and other films show the power station and the substation, timestamped as follows:
The Place Where I Worked (1960s)
Atomic Power Station (1962)
Bradwell Atomic Power Station (1962)
In 1969, the power station had a new computer installed to monitor the temperature of its reactors; the Honeywell 316. Whilst this resembles somewhat of a joke by modern standards, it was still in use until 2000 when it finally packed up. In 1999, it was announced that the power station's planned obsolescence would mean it would stop generating by 2002. This made it the first nuclear power station with a planned closure in the UK. All spent fuel was removed by 2005, with the turbine hall demolished in 2011 and underground waste storage vaults (hmm) emptied by 2016. Final demolition was complete by 2019, with the two reactors having been cladded inside 34,000 square metres of weatherproof aluminium sheeting to allow for radiation to finally decay. The buildings have been locked until 2083 when final clearance is planned, quite fascinating really. The date scheduled for completion of full dismantling is 2104. Despite all that effort, China wants to build a 2,200MW Bradwell B nuclear power station next door.
The 132kV Substation
In contrast to the power station, there's not a whole lot to say about the substation itself. It can be presumed that the substation was constructed at the same time as the power station, and served the purpose of receiving the freshly-generated electricity from the reactor and transforming it for delivery across the National Grid's powerlines, still visible at the back of the substation. The electricity would then be sent to Rayleigh Main Substation, still in use today and visible from the A130, which then distributed the electricity locally around Essex. It apparently was designed for 275kV before being scaled down to 132kV, perhaps like the power station's output. At the centre of the transformers and plinths is a rectangular brick control building, where the substations controls and monitoring equipment is. Whilst the building appears plain on the outside, it still has some architectural flair.
Several 1960s' British Pathe and other films show the power station and the substation, timestamped as follows:
The Place Where I Worked (1960s)
Atomic Power Station (1962)
Bradwell Atomic Power Station (1962)
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These 1960s' film stills show the building (right and bottom)
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The transformers in colour in 1962.
The Explore
The story begins when I recently came across @Speed 's cracking report which you should check out first here: https://www.28dayslater.co.uk/threads/bradwell-132kv-substation-essex-sept-2019.121085/. I can't take any credit for this find so send it all his way, and I have to say I was pretty impressed with this very original find. Having grown up playing on the Essex marshes and spent many later years walking them, it is safe to say I've seen a lot of what there is to explore. But when I saw this gem crop up, I had to take a look. This might be the closest you can get to ever exploring part of a nuclear power station, which is what this is. It's also probably one of the very few substations you can explore without getting cooked to ash. Whilst its pretty obvious it is completely disconnected from the grid with its notable lack of wires or humming, I'm not an electrics expert so understandably if it wasn't for knowing this was doable already I would've probably steered well clear. Given that it's directly opposite two nuclear reactors in the process of dismantling, discretion was key. We surveyed the perimeter and its numerous 'Danger of Death' signs, and couldn't find any good way in without climbing. However, after pressing through some undergrowth and surveying another section, I noticed a very clever and subtle access point just before turning to leave.
We soon found ourselves inside the complex and proceeded to work our way around the control building. We made it into several of its supporting rooms which were only accessible from the outside. The central control room proved a puzzle until we noticed the cable ducting under the floor, covers conveniently lifted by a certain someone. Huge respects for doing that first because sliding under a wall via a narrow concrete channel over several meaty uninsulated wires takes balls. As I made my way under, I suddenly felt a sharp pain in my hand and then realised I couldn't move. Well, fortunately it was merely a splinter and there was no wiggle room, but for a second I thought I was in the process of being fried alive. Anyway, we made it into what was a very tidy control room, sunlight entering via its simple yet tasteful modernist windows at either end. Nothing on the outside suggested something of this quality lie within, another reason why Speed did well to discover this.
We worked our way through a dining room, toilet and key room which were less nice, before exiting and checking out its other outer rooms. We had a little look around the overgrown transformers but didn't want to venture too far into view of the road. On the whole, this was a real gem even if it's pretty small. Its architecture is dull and unassuming, but there is a certain beauty about the way control rooms are designed to let in natural light that harks back to the 1930s' era of Battersea and Kelenfold. It was really nice to see something so interesting and in good shape within previously explored territory that I had no idea existed. Now I've been googling substations all day, such are the joys of urbex - rock and roll.
The Explore
The story begins when I recently came across @Speed 's cracking report which you should check out first here: https://www.28dayslater.co.uk/threads/bradwell-132kv-substation-essex-sept-2019.121085/. I can't take any credit for this find so send it all his way, and I have to say I was pretty impressed with this very original find. Having grown up playing on the Essex marshes and spent many later years walking them, it is safe to say I've seen a lot of what there is to explore. But when I saw this gem crop up, I had to take a look. This might be the closest you can get to ever exploring part of a nuclear power station, which is what this is. It's also probably one of the very few substations you can explore without getting cooked to ash. Whilst its pretty obvious it is completely disconnected from the grid with its notable lack of wires or humming, I'm not an electrics expert so understandably if it wasn't for knowing this was doable already I would've probably steered well clear. Given that it's directly opposite two nuclear reactors in the process of dismantling, discretion was key. We surveyed the perimeter and its numerous 'Danger of Death' signs, and couldn't find any good way in without climbing. However, after pressing through some undergrowth and surveying another section, I noticed a very clever and subtle access point just before turning to leave.
We soon found ourselves inside the complex and proceeded to work our way around the control building. We made it into several of its supporting rooms which were only accessible from the outside. The central control room proved a puzzle until we noticed the cable ducting under the floor, covers conveniently lifted by a certain someone. Huge respects for doing that first because sliding under a wall via a narrow concrete channel over several meaty uninsulated wires takes balls. As I made my way under, I suddenly felt a sharp pain in my hand and then realised I couldn't move. Well, fortunately it was merely a splinter and there was no wiggle room, but for a second I thought I was in the process of being fried alive. Anyway, we made it into what was a very tidy control room, sunlight entering via its simple yet tasteful modernist windows at either end. Nothing on the outside suggested something of this quality lie within, another reason why Speed did well to discover this.
We worked our way through a dining room, toilet and key room which were less nice, before exiting and checking out its other outer rooms. We had a little look around the overgrown transformers but didn't want to venture too far into view of the road. On the whole, this was a real gem even if it's pretty small. Its architecture is dull and unassuming, but there is a certain beauty about the way control rooms are designed to let in natural light that harks back to the 1930s' era of Battersea and Kelenfold. It was really nice to see something so interesting and in good shape within previously explored territory that I had no idea existed. Now I've been googling substations all day, such are the joys of urbex - rock and roll.
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as I say it was 
