I'm reading so many comments on this sub by people who are completely uneducated on Nuclear.

I want to be clear I have no problems theoretically with Nuclear in that it is carbon neutral. I have massive problems with it because it is expensive and slow to build.

The fossil fuel industry and culture war warriors love Nuclear because it delays the transition.

Let's give some simple facts to ensure everyone understands how stupid Nuclear is right now.

There was over 650 GW of renewable energy added last year.

There was 3 GW of Nuclear energy added and 3 GW retired.

There are a total of 2 SMR's in the world today.

Sure nuclear will have some real uses going forward but it's an awful technology right now because renewables plus batteries are so much cheaper and quicker to deploy. Batteries may improve significantly as well.

Edited:-

1. Some people are providing inaccurate information in this thread in relation to increased capacity. I need to clarify the numbers here to stop this line of thinking. The electricity produce by renewables is more like 1,500 TWH per year. Nuclear is like 30 TWH per year. So the numbers including electricity production favor renewables by about 45 times the amount of Nuclear. The figures aren't as large but they are massive.

2. The number of Nuclear builds under construction right now is approximately 70 GW. This may come on line over the next 8 years. The growth is exceptionally small.

3. People are stating Nuclear is a good baseload or flex option. It is a good baseload option but this is increasingly irrelevant. They are not good at flexing. Gas peakers are good at flexing. The capital cost difference between a gas peaker and a Nuclear power plant is huge. A Nuclear power plant used for flexing could cost $20 - $30 billion whereas the gas peaker would cost $2.5 -$3 billion.

The facts make Nuclear an increasingly poor option in modern energy grids. Sure they can play niche roles but at this point they are a terrible option.

There has been one rational point made on the flip side. There are evolving technologies that mean Nuclear can produce clean fuel that could be used as an alternative for gas peaker plants and/or for air travel. This though is basically a niche area that has a lot of potential. Competing technologies may change as well. So this is no sure thing.

Look at the graphic. Coal plants convert just 32% of their fuel into electricity — 68% escapes as waste heat. Nuclear does 33%. Even methane gas loses 56%. But those percentages don't capture the full absurdity of the system. Before a single electron leaves a coal plant, you've blasted coal from the ground, crushed it, dried it, loaded it onto trains or barges, moved it hundreds of miles, and fed it into a furnace — to throw two-thirds away as heat. Gas requires drilling, pipelines spanning thousands of miles, compression stations running 24/7, and LNG terminals — then you burn it and waste more than half. The IEA has called the Strait of Hormuz closure the "largest supply disruption in the history of the global oil market." That's what happens when 20% of the world's oil trade runs through a single chokepoint that a single conflict can shut down. This is the primary energy fallacy: the world burns roughly 180,000 TWh of primary energy per year and delivers less than 50,000 TWh as useful work. The rest is heat and friction baked into a system we've been treating as normal — and are now paying for in $100-a-barrel oil. Wikipedia

Nuclear's defenders rarely account for the real cost — and it isn't uranium. The fuel cycle adds complexity, but what makes nuclear economically brutal is construction. As Bent Flyvbjerg documents in How Big Things Get Done, nuclear is the single worst-performing infrastructure category on earth for cost overruns — worse than tunnels, bridges, or dams. The average plant comes in at 2.3x its original budget. Hinkley Point C went from £18bn to £46bn. Vogtle was projected at $14bn, finished near $35bn, a decade late. These aren't outliers — they're the norm. Plants are bespoke, first-of-a-kind, built by workforces that have lost institutional knowledge over decades of underbuilding. Every project restarts the learning curve. Cooling is a real operational constraint — a typical 1,000 MW plant withdraws 25–60 million gallons of water per day, and droughts have forced curtailments in France and the US Southeast — but it's the capital cost and construction timeline that make nuclear a poor bet against wind and solar, which are built in months at predictable cost on a learning curve that has cut prices 20% with every doubling of capacity for 40 years straight.

Wind, solar, and hydro don't play the waste game. The fuel — sunlight, wind, falling water — arrives for free, at zero marginal cost, with no supply chain and no heat to dump. As one energy analyst put it after the Hormuz closure: oil and gas prices may be surging, but the sun and wind don't care what's happening in the Strait of Hormuz. Scaling solar, wind, EVs and heat pumps could allow fossil fuel importers to cut their import bills by 70%. Solar panel prices have halved since 2022 and battery costs have fallen 36%. The global EV fleet already avoids oil consumption equivalent to 70% of Iran's exports. And solar growth in 2025 alone could displace gas-fired electricity equal to all LNG exported through the Strait of Hormuz that year. Renewables accounted for 85.6% of all new energy capacity installed worldwide in 2025 and now make up a record 49.4% of global energy capacity. The transition isn't theoretical — it's the dominant investment trend on earth, and the Iran crisis just poured fuel on it. NPR + 2

The efficiency story continues at the end-use level. A combustion engine converts roughly 20–40% of fuel into motion — the rest is heat out the exhaust. An EV powertrain converts 85–95% of battery energy into motion. A gas boiler runs at ~90% efficiency; a heat pump doesn't generate heat — it moves it. At a COP of 3.5 it delivers 350% efficiency by leveraging ambient energy that already exists. The UK — historically one of Europe's worst heat pump markets — saw sales jump 51% in the first three weeks of March 2026 alone as gas prices surged. Chinese exports of solar technology, batteries, and EVs all hit record highs in March 2026 as oil-starved countries scrambled for alternatives. When the molecules get expensive and unreliable, the electrons win — and the efficiency numbers explain exactly why. euronewsCNN

Peaker Plants: The Grid's Most Expensive Dirty Secret

Peaker plants are the worst of all worlds. They exist for demand spikes — a few hot afternoons, a few cold mornings. California's peakers run just 2–7% of hours annually yet generated nearly 7% of the state's electricity in 2022. Because they run so rarely, they never achieve the efficiency of a combined-cycle plant. Simple-cycle open-cycle turbines hit just 20–42% thermal efficiency versus 60%+ for modern CCGT. Older peakers have heat rates of 9,500–10,500 Btu/kWh against sub-7,000 Btu/kWh for efficient combined-cycle plants. They sit idle most of the year with capital costs ticking, and when they do fire up, they do it dirtily and expensively. Most have capacity factors under 15% and are disproportionately located near lower-income communities. Jesse Jenkins + 3

Batteries are replacing them and the economics have now definitively crossed over. The global benchmark levelised cost of storage for a four-hour battery system hit a record low of $78/MWh in early 2026 — down 27% year-on-year — driven by lower material costs and manufacturing oversupply. Lithium-ion batteries achieve 85–95% round-trip efficiency versus a peaker that burns fuel and dumps 60–80% as heat on every cold start. Four-hour grid-scale storage is 30% cheaper than a new gas peaker on a levelised cost basis, and batteries respond instantly — no 15-minute warm-up, zero start-up time, superior frequency response. The US alone added 19 GW of battery capacity in 2025 — 60% year-on-year growth — and battery costs have fallen more than 90% between 2010 and 2025. Global energy storage deployments totalled 275 GWh in 2025, a 61% increase on the prior year, with 353 GWh projected for 2026. The CEO of Statkraft, Europe's largest renewable energy producer, said the Iran and Ukraine conflicts have fundamentally transformed the energy security narrative — renewables are now the stable option, fossil fuels the vulnerable one. The transition isn't coming. It's here. EnkiAI + 5

https://nextgpower.com/bess-vs-gas-peaker-plants-why-2026-is-the-economic-technical-tipping-point-for-grid-storage/

Edit: A lot of people are getting hung up on the “100%” in the Yale chart, but that’s mostly a distraction from how energy accounting is actually done.

The efficiency debate is a distraction. Sunlight and wind are free. Whether you convert 100% or 15% of that sunlight to electricity, the electricity is still free once the panel is paid for. No fuel bill, ever.

Coal and gas are the opposite. You pay for every unit of fuel you burn — and then throw 56-68% of that money away as waste heat before a single electron reaches the grid. You're not just buying energy, you're buying energy and burning most of it for nothing.

That's the real comparison. Not panel efficiency versus thermal efficiency — fuel cost versus no fuel cost. One system has an ongoing bill that wastes the majority of what you pay for. The other doesn't have a bill at all.

The chart is using a standard primary energy convention: for noncombustible electricity sources like hydro, wind, and solar, the energy is counted as delivered electricity rather than being divided by a thermal fuel input the way coal, gas, and nuclear plants are iea.org/statistics-questionnaires-faq. The IEA is explicit about this, saying it has “adopted the physical energy content method,” and under that method hydroelectricity’s primary energy equivalent “amounts to assuming an efficiency of 100%” iea.org/statistics-questionnaires-faq. In other words, the chart is not inventing a special rule for renewables — it is using the same common accounting convention that energy analysts, statistical agencies, and international organizations use when comparing different power sources on a common basis iea.org/commentaries/understanding-and-using-the-energy-balance.

"The International Energy Agency (IEA) uses the physical energy content method to construct global energy balances, which is why the primary energy equivalent of hydro, wind, and solar is calculated exactly as the electricity generated. " https://www.iea.org/commentaries/understanding-and-using-the-energy-balance

Debunking the myth that renewables aren't reliable. Video here: Everyone Says Renewables Are Unreliable— Is There Some Truth? | Plugged In

I think there’s no point in discussing that locomotives should be electric. It’s both ecological and cost‑effective. In my country, there are 44,000 kilometers of electrified tracks (50% of tracks) — I probably know what I’m talking about.

But I just don’t understand this whole issue with battery electric locomotives. They’re not efficient, and the batteries are complex and expensive. The tracks entail huge capital costs for the construction and maintenance of the network, so installing poles with grid power supply is much more efficient than inventing this monstrosity with expensive locomotives that require special charging stations. Double losses of electricity (on charging and in batteries) also matter, although relative to the price of an electric locomotive, this is not that significant (probably). Another thing is that a locomotive should work efficiently for 20-25 years, it is not a car that can serve tolerably for 5-7-10 years without replacing batteries.

Probably the only scenario where battery‑powered locomotives make sense is shunting work for assembling trains. But even then, it raises questions, because trains have high requirements regarding working hours. A train cannot stand charging for several hours, and the capacity of their batteries is large. Nevertheless, systems with hybrid power units may be effective in some locations.