New Study Casts Doubt on Cheap Fusion Power Future

Fusion power holds the promise of a future with steady, zero-emissions electricity, a vision that has attracted billions in public and private funding. However, a new study published in Nature Energy suggests that even if this ambitious future materializes, the electricity it provides might not be cheap. While technologies typically become more affordable over time – like lithium-ion batteries, which are 90% cheaper than in 2013 – the pace of this cost reduction varies significantly across different innovations, and fusion might not follow the rapid decline seen in solar or battery technologies. To better predict the future cost trajectory of fusion, researchers focused on a crucial metric: the "experience rate." This rate quantifies the percentage by which an energy technology's cost declines every time its installed capacity doubles. Historically, highly successful renewable technologies boast high experience rates: onshore wind power at 12%, lithium-ion batteries at 20%, and solar modules at an impressive 23%. In contrast, nuclear fission, a more complex and established technology, has an experience rate of just 2%, indicating a much slower path to cost reduction. The study's methodology involved interviewing a wide array of fusion experts from both public and private sectors. These experts evaluated fusion power plants based on three key characteristics known to correlate with experience rate: unit size, design complexity, and the need for customization. The consensus was clear: fusion plants will be relatively large, similar to other heat-generating facilities. While they may require less customization than fission plants due to simpler regulatory frameworks, they will still need more tailoring than mass-produced items like solar panels. Crucially, as Lingxi Tang, a co-author from ETH Zurich, noted, there was "almost unanimous agreement that fusion is incredibly complex," with some experts even stating it was off the scale provided. Based on these expert evaluations, the researchers propose an experience rate for fusion between 2% and 8%. This projection suggests that fusion power will see a faster price reduction than traditional nuclear fission but will lag significantly behind the dramatic improvements observed in many contemporary energy technologies. This slower rate implies that achieving a substantial drop in the cost of building a fusion reactor would necessitate extensive deployment over a considerable period, meaning electricity from fusion plants could remain expensive for an extended duration. This finding sharply contrasts with many current modeling studies that often assume a more optimistic experience rate of 8% to 20%. The implications of these findings are substantial for global energy investment. Tang questions the current levels of funding, pointing out that the US allocated over $1 billion to fusion in fiscal year 2024, with private sector funding totaling $2.2 billion between July 2024 and July 2025. "If you’re talking about decarbonization of the energy system, is this really the best use of public money?" he asks. However, some experts, like Egemen Kolemen from Princeton Plasma Physics Laboratory, caution against over-reliance on historical data. He highlights how analysts in 2000 wrongly predicted solar power would remain expensive, only for prices to crash due to massive production increases, particularly from China. Kolemen emphasizes that unforeseen factors like regulations, geopolitical dynamics, and labor costs will ultimately determine the future price, concluding, "We haven't built the thing yet, so we don't know."