Recently nuclear fusion has seen several breakthroughs. One of them happened on the 5th of December 2022, when a research team achieved “ignition” at the National Ignition Facility part of the Lawrence Livermore National Laboratory in California[1]. In other words, for the first time, a fusion reactor has produced more energy that was used to trigger the reaction. This was done by firing 2.05 megajoules of energy toward a cylinder holding a pellet of frozen deuterium and tritium, isotopes of hydrogen. « The pellet compressed and generated temperatures and pressures intense enough to cause the hydrogen inside it to fuse ». The resulting fusion of the atomic nuclei released 3.15 megajoules of energy (Q= 1.54).
The ability to release energy under controlled nuclear fusion had already been demonstrated, for the first time in 1994, when the Tokamak Fusion Test Reactor (TFTR) of Princeton Plasma Physics Laboratory produced 10.7 MW of fusion power[2].
The demonstration of the technical feasibility of the energy use of nuclear fusion is the current objective of the International Thermonuclear Experimental Reactor project (ITER), built in Cadarache, France. The goal is to “generate 500 MW of fusion power in its plasma for long pulses”, the reactor is designed to “yield in its plasma a ten-fold return on power (Q=10)” meaning it will produce 500 MW of fusion power from 50 MW of heating power. The project is set to break to world record for fusion power in a magnetic confinement fusion device, currently held by the Joint European Torus, which produced 16 MW of fusion power from a total input heating power of 24 MW (Q=0.67), in 1997. ITER aims to be the first magnetic confinement fusion experiment to generate net energy.
ITER is supposed to be commissioned in 2025 and to achieve 500 MW burning fusion plasma in 2035[3].
ITER will not convert the heating power produced as electricity, it’s the aim of a separate project called DEMO, a demonstration powerplant. The construction of DEMO is foreseen to start in the 2030s and its operation in the 2040s.
Implying that commercial nuclear fusion reactor is not to be expected before the 2050s[4].
The environmental impact of fusion power plants will be comparable to the impact of renewable resources:
In a paper detailing the hypothetical economy of fusion energy and comparing costs of electricity between future fusion power plants and other type of power plants, a research team of the Institute of Plasma Physics of the CAS, used the European methodology, ExternE for the evaluation of external costs of energy concluded that fusion (DEMO2 input model data) would have the lowest external cost among all the benchmark types of power plants[5].
With a calculated average external cost of 1$/MWh, it is lower than the main renewable energy resources, on and offshore wind turbine with respectively 4.7 and 2.7$/MWh or large solar powerplant with 16$/MWh and considerably lower than the external cost of nuclear fission with an average of 23$/MWh and that of fossil energy (39$ for natural gas and 100$ for coal).
The European methodology “assesses three main categories of the energetics impact: damage to human health (increased risk of mortality and morbidity), effects on ecosystems and biodiversity (changes in the environment, biodiversity loss) and the impact on resources and depletion (mainly of water, metals and fuels, but also crops, buildings, etc.). The impacts include climate change, ozone depletion, soil acidification, eutrophication of freshwater and marine environments, increasing the toxicity of the environment, increasing background radiation, land appropriation, annexation of areas in cities, transforming the natural soil, depletion of water resources, depletion of mineral deposits, exploitation of energy resources and disasters and accidents”[6].
The external costs are low because unlike nuclear fission, nuclear fusion does not create any long-lived radioactive waste and fusion reactors are inherently safer than fission ones[7].
[1] Scientists achieve a breakthrough in nuclear fusion. Here’s what it means. (nationalgeographic.com)
[2] Tokamak Fusion Test Reactor | Princeton Plasma Physics Laboratory (pppl.gov)
[4] art.torvergata.it/bitstream/2108/132174/1/JG12.356-web.pdf
[5] https://doi.org/10.1016/j.energy.2018.03.130
[6] https://doi.org/10.1016/j.energy.2018.03.130
[7] Fusion – Frequently asked questions | IAEA
