Every two years, I keep coming back to one big question -- are Small Modular Reactors really a good idea, or are we chasing a dream that may not work out? I made videos on this in 2020, 2022, and 2024, and honestly, with each video, I became a little more doubtful. So as we move through 2026, let us once again look at where this debated technology really stands today.

For those who are new to this topic, Small Modular Reactors, or SMRs, are basically small nuclear reactors that produce up to 300 megawatts of electricity.

Most of them use proven light water reactor technology, while some companies are working on advanced designs like molten salt reactors and high-temperature gas reactors.

There is even a company called Nano Nuclear Energy Inc that is building extremely tiny reactors called Loki MMR and Kronos MMR, which produce only a few megawatts. Their first demonstration is planned at Idaho National Laboratory around 2027.

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Supporters of SMRs make three main promises. First, since these reactors are modular, many parts can be built inside factories and then transported to the site, instead of slowly building everything in the open for years.

Second, the same design can be repeated again and again, which means mass production should bring down costs over time, just like how aircraft and wind turbines became cheaper after repeated production.

Third, SMRs are designed with passive safety, meaning if something goes wrong, natural forces like gravity, pressure, and heat flow shut the reactor down automatically -- no need for electricity, motors, or even human action. Just like a hot cup of tea cools down by itself.

But the biggest worry is economics. Traditionally, nuclear power becomes cheaper only when reactors are built very large, because expensive things like safety systems, approvals, and staff costs get spread over huge electricity production. When you make reactors smaller, costs do not reduce in the same way. Many fixed expenses still remain. Mass production could help, but only if a huge number of identical SMRs are built -- something the nuclear industry has rarely achieved.

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In nuclear language, the first reactor of a new design is called FOAK, or First-of-a-Kind, which is always slow and expensive because everyone is learning. After many units are built, it becomes NOAK, or Nth-of-a-Kind, where costs may finally fall.

The problem is, today many companies across the world are working on different SMR designs, all competing for the same market. So reaching that NOAK stage is not so easy.

Fuel is another headache. Many advanced SMRs need a special fuel called HALEU, where Uranium is enriched between 5% and below 20%. This fuel allows reactors to run longer and produce more power from a smaller size. But large-scale HALEU production outside Russia is still very limited.

The US Department of Energy and companies like Centrus Energy are trying to build local supply, but this system is still new. Some experts also worry that advanced reactors may produce different or even larger amounts of nuclear waste, though the industry disagrees.

Then there is the opportunity cost question. Solar, wind, and battery storage are growing very fast, and their costs are falling rapidly. Critics ask -- why spend huge money on SMRs which may not become commercial until the 2030s, when renewables and batteries may already fill the gap by then? Supporters reply that the world will still need stable, reliable low-carbon electricity for times when there is no sun or wind.

Why then are governments still backing SMRs strongly? The Russia-Ukraine war and Middle East tensions have shaken global energy supplies, and countries now want secure, independent energy sources.

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SMRs could also be built on old coal plant sites, saving time and using existing grid connections and skilled workers. Some advanced reactors could even provide high heat for steel, cement, and green hydrogen production.

But reality is harsh. According to the World Nuclear Association, only two SMRs are actually operating today. Russia's floating plant Akademik Lomonosov was completed in 2020, almost 10 years late. China's Shidaowan project took 11 years and cost about $430 million, yet produces only a little over 210 megawatts. If even China struggles, doubters surely have a point.

So the real question is no longer whether SMRs are good or bad. The honest question is -- can they really be built fast enough, cheaply enough, and in large enough numbers to help fight climate change before time runs out? That answer, sadly, nobody can give with full confidence today.

The author is a Defence, Aerospace & Geopolitical Analyst.