Study finds fusion power unlikely to beat renewables on cost, warns ETH Zurich researchers

TL;DR A new study from ETH Zurich suggests fusion power may not achieve cost competitiveness with renewable energy sources. Researchers found that fusion technology's cost reduction rate will likely be slower than commonly assumed.

**Context** Fusion power, which merges atomic nuclei to generate vast energy, holds promise for clean electricity production, akin to how the sun produces its energy. Proponents often highlight its potential for exceptionally low energy costs. However, new research published in *Nature Energy* by scientists at ETH Zurich challenges these long-term cost projections, suggesting fusion may struggle to outcompete existing renewables.

**Key Facts** Professor Tobias Schmidt, a senior author of the paper, expressed curiosity regarding the unusually low "levelized cost" promises—the total cost of building and operating a power plant over its lifespan, divided by the total energy output—made by some within the fusion sector. To investigate this, the ETH Zurich team developed a framework to assess "experience rates" for technologies. An experience rate quantifies the percentage cost reduction that occurs when the cumulative deployment of a technology doubles.

Using this methodology, the researchers compared two primary fusion approaches—magnetic fusion and inertial fusion—against other energy solutions. They estimated that fusion power plants will likely exhibit lower experience rates than earlier projections indicated. This implies that the cost of fusion technology will decline at a slower pace than previously anticipated. Lingxi Tang, the paper's first author, stated that this study is the first to offer an evidence-backed range of experience rates for fusion, revealing a significant gap between prior assumptions and a more realistic range for the technology.

**What It Means** These findings suggest that current investment models and policy assumptions for fusion energy may be overly optimistic. The slower cost decline could make it challenging for fusion power to achieve widespread economic viability compared to more mature and rapidly developing renewable energy technologies. The study's implications could prompt a reevaluation of funding priorities, potentially redirecting resources towards accelerating the deployment of established clean energy solutions. Further research will continue to assess the cost dynamics of emerging energy technologies.