Fusion's Illusion

Our sun (and all the other stars) use nuclear fusion to produce massive amounts of radiated energy. Nuclear fusion releases its energy, by forcing small atoms (largely hydrogen) to combine into larger elements. There has been great excitement with news that the National Ignition Facility at Lawrence Livermore National Laboratory in California have demonstrated a net energy gain from nuclear fusion on Earth (https://www.theguardian.com/environment/2022/dec/13/what-is-nuclear-fusion-what-have-scientists-achieved-ignition). This news has reignited the claim that nuclear fusion has the potential 'to provide a near limitless, safe, clean (no carbon is involved) source of energy.' The word 'potential' is most important. The folk at Lawrence Livermore used a really powerful laser to direct 2.05 MegaJoules (MJ) of heat energy at a tiny amount of hydrogen 'fuel'. The resulting nuclear fusion, released 3.15 MJ of energy. Although this establishes that nuclear fusion works in priciple, this energy gain is only sufficient to boil a few kettles of water. The world is light-years away from being able to replace coal, oil, gas and wood by nuclear fusion. In the hype, it would be most unfortunate, if this positive news on nuclear fusion, was used to distract an urgent transition away from using non-renewables. If civilisation survives long enough, nuclear fusion may eventually become an important driver of human technologies. This technology won't, however, save the planet from the coming climate emergency.