Fusion at scale: Critical enablers in global energy transitions

Fusion is a promising sustainable energy source that can potentially contribute to achieving the most ambitious climate goals with firm carbon-free baseload electricity. Due to recent advancements, fusion is transitioning from a purely research stage to a pre-commercialisation phase. However, many aspects related to its commercialisation are uncertain. Energy scenarios within the EUROfusion TIMES model (ETM) have been used to explore the conditions that could enable fusion to play a significant role in a future decarbonised global energy system, assuming moderate socio-economic development. The results indicate that a maximum share of 21% in a ∼140 PWh global electricity generation is achievable by 2100 under the following concurrent conditions: fusion is commercialised by 2040; the capacity doubling time is as large as that experienced by fission in the ‘70s and a stable tritium supply chain is established; the average overnight cost of the first fleet of fusion plants does not exceed 7200 USD/kW with a learning rate of 10%, and solar and wind generation is limited to 75% in each model timeslice. In contrast, the share of fusion under the most conservative assumptions reaches only a few percent, despite corresponding to an operating fleet comparable in size to the current fission fleet. The study also proves two insights: firstly, that early availability alone cannot guarantee high fusion shares in power markets. Secondly, deployment speed along with restriction to variable renewable energy contribution are dominant structural factors.