On April 6, 2026, India reached a significant milestone in its nuclear energy journey. The Prototype Fast Breeder Reactor (PFBR), a 500 MWe (megawatt electric) reactor located at Kalpakkam in Tamil Nadu, achieved first criticality at 8:25 PM IST. This means the reactor initiated a self-sustaining nuclear chain reaction for the first time a controlled process where the number of neutrons produced equals those lost, allowing the reactor to operate steadily.
The PFBR is indigenously designed and built by Indian scientists and engineers, primarily under the Department of Atomic Energy (DAE) and the Indira Gandhi Centre for Atomic Research (IGCAR). It uses sodium-cooled fast breeder technology with mixed oxide (MOX) fuel made from plutonium and uranium recovered from spent fuel of earlier reactors. Unlike conventional reactors, fast breeder reactors can produce more fissile material (fuel) than they consume, making them highly efficient.
iconiclabs on
All the cool kids been on fusion for ages now though
MegaDingo5plus on
With all the pastel colours and chimneys I would have thought this was just a very serious ice cream factory
tesakills on
Vijigishu on
India’s nuclear plants are also colorful 🙂
Abhi_4178 on
Had they not achieved controlled Nucear fission so far.
Were not they already running Atomic Power Plants?
WetAndMeaty on
I thought this was a Minecraft screenshot at first
[deleted] on
[deleted]
Time_Seaworthiness43 on
They should burn their trash. That’s sustained energy for them.
synthsnstuff84 on
If it’s like their space program, it will fail.
ckc1151 on
Not sure why people are putting them down, NGL I’m not a fan of India in the slightest
But I think this is a great achievement even for them
Thick-Ad-4168 on
Shitty title , India had achieved sustained nuclear fission in the 60’s itself as literally every commercial reactor on earth works on sustained nuclear fission.
This reactor is special because it creates more fuel than it consumes , and makes India one of the only 2 countries on earth with commercial breeder reactors
New_Horse3033 on
That looks like a copy of Chernobyl’s reactor #4?
CalmestUraniumAtom on
misleading title
[deleted] on
[deleted]
brknmad on
Um, shit?
waffleking9000 on
Gives off Dr Seuss vibes
BS-Calrissian on
sorry for being a hater but I have a bad feeling about this
Upset-Disaster1907 on
It’s hard to look past all the evil things that go down in India.
i_just_farted123 on
What a shitty title, minimizing a great achievement.
The criticality was achieved in a Fast Breeder Reactor(FBR). It’s a type of reactor that produces more nuclear fuel than it consumes by turning unusable uranium isotopes into an isotope that can produce energy.
Only the SECOND in the whole world btw.
It’s a major step in India being able to utilise its vast reserves of thorium to achieve independence for polluting fossil fuels
tetten on
“What do we do with the run off?” “A direct pipe to our sacred and holy river Gagnes of course!”
Spartan_S134 on
Why the hell is the UK government sending them aid every year when they have this and a space program that the UK does not even have. Xox
ThatShadyJack on
Ayo let’s go!
popmeer_on_call on
OP please explain the audience what’s actually happening and what’s special here.
This is the first time India reached the criticality of Thorium based nuclear fuel. It’s the 2nd country to do this after Russia. Many developed countries (US,UK,Japan,Germany) dropped trying this as it’s technically and financially difficult (and availability of uranium)
India has a 3 step plan to use Thorium as a fuel – that can power the country for the next 1000 years. India has rich Thorium deposits (found simply on the beach sands) and very less uranium.
Stage 1 – use Uranium to generate plutonium 239
Stage 2 – use plutonium 239 from stage 1 to generate uranium 233 from Thorium 232. Thorium is not fissile but uranium 233 is fissile – hence this stage creates more fissile material than it consumes – hence called breeder reactor.
Stage 3 – uses 233 from stage 2 to get electricity
This 3 stage plan was conceived 50 years ago and is now bearing results.
HonestEgg1973 on
Well we all know India takes workplace safety seriously and Indians are not know for scams so everything should be just fine. 🤣
s04ep03_youareafool on
Misleading title btw.
Actually,they unlocked a 3stage reactor that can produce more fuel than it had before,to further drive the process
ViniusInvictus on
Sustaining a nuclear reaction isn’t the news – that happens in any functional nuclear power plant – sustaining it with a thorium cycle is what is new.
27 Comments
On April 6, 2026, India reached a significant milestone in its nuclear energy journey. The Prototype Fast Breeder Reactor (PFBR), a 500 MWe (megawatt electric) reactor located at Kalpakkam in Tamil Nadu, achieved first criticality at 8:25 PM IST. This means the reactor initiated a self-sustaining nuclear chain reaction for the first time a controlled process where the number of neutrons produced equals those lost, allowing the reactor to operate steadily.
[indiatoday.in](http://indiatoday.in)
The PFBR is indigenously designed and built by Indian scientists and engineers, primarily under the Department of Atomic Energy (DAE) and the Indira Gandhi Centre for Atomic Research (IGCAR). It uses sodium-cooled fast breeder technology with mixed oxide (MOX) fuel made from plutonium and uranium recovered from spent fuel of earlier reactors. Unlike conventional reactors, fast breeder reactors can produce more fissile material (fuel) than they consume, making them highly efficient.
All the cool kids been on fusion for ages now though
With all the pastel colours and chimneys I would have thought this was just a very serious ice cream factory
India’s nuclear plants are also colorful 🙂
Had they not achieved controlled Nucear fission so far.
Were not they already running Atomic Power Plants?
I thought this was a Minecraft screenshot at first
[deleted]
They should burn their trash. That’s sustained energy for them.
If it’s like their space program, it will fail.
Not sure why people are putting them down, NGL I’m not a fan of India in the slightest
But I think this is a great achievement even for them
Shitty title , India had achieved sustained nuclear fission in the 60’s itself as literally every commercial reactor on earth works on sustained nuclear fission.
This reactor is special because it creates more fuel than it consumes , and makes India one of the only 2 countries on earth with commercial breeder reactors
That looks like a copy of Chernobyl’s reactor #4?
misleading title
[deleted]
Um, shit?
Gives off Dr Seuss vibes
sorry for being a hater but I have a bad feeling about this
It’s hard to look past all the evil things that go down in India.
What a shitty title, minimizing a great achievement.
The criticality was achieved in a Fast Breeder Reactor(FBR). It’s a type of reactor that produces more nuclear fuel than it consumes by turning unusable uranium isotopes into an isotope that can produce energy.
Only the SECOND in the whole world btw.
It’s a major step in India being able to utilise its vast reserves of thorium to achieve independence for polluting fossil fuels
“What do we do with the run off?” “A direct pipe to our sacred and holy river Gagnes of course!”
Why the hell is the UK government sending them aid every year when they have this and a space program that the UK does not even have. Xox
Ayo let’s go!
OP please explain the audience what’s actually happening and what’s special here.
This is the first time India reached the criticality of Thorium based nuclear fuel. It’s the 2nd country to do this after Russia. Many developed countries (US,UK,Japan,Germany) dropped trying this as it’s technically and financially difficult (and availability of uranium)
India has a 3 step plan to use Thorium as a fuel – that can power the country for the next 1000 years. India has rich Thorium deposits (found simply on the beach sands) and very less uranium.
Stage 1 – use Uranium to generate plutonium 239
Stage 2 – use plutonium 239 from stage 1 to generate uranium 233 from Thorium 232. Thorium is not fissile but uranium 233 is fissile – hence this stage creates more fissile material than it consumes – hence called breeder reactor.
Stage 3 – uses 233 from stage 2 to get electricity
This 3 stage plan was conceived 50 years ago and is now bearing results.
Well we all know India takes workplace safety seriously and Indians are not know for scams so everything should be just fine. 🤣
Misleading title btw.
Actually,they unlocked a 3stage reactor that can produce more fuel than it had before,to further drive the process
Sustaining a nuclear reaction isn’t the news – that happens in any functional nuclear power plant – sustaining it with a thorium cycle is what is new.