Nuclear power and AI: Is fission or fusion better?

The race to expand nuclear energy capacity is intensifying as countries and tech giants seek clean power solutions for growing energy demands, particularly from AI data centers.

Current landscape and strategic shifts: The nuclear energy sector is experiencing renewed interest with over 20 nations committing to triple their nuclear capacity by 2050.

• Major tech companies including Microsoft, Google, Amazon, Meta, and OpenAI are exploring nuclear options to power their energy-intensive data centers
• Microsoft has recently secured two significant agreements: a Power Purchase Agreement (PPA) with fusion company Helion and a 20-year PPA to restore the Three Mile Island Unit 1 fission facility

Understanding the nuclear options: Nuclear energy production occurs through two distinct processes – fission and fusion – each with their own technological and practical considerations.

• Fission, which has powered the U.S. electrical grid since the 1950s, remains the more established and commercially viable option
• Fusion technology, despite promising cleaner and safer energy with higher density, has consistently fallen short of development expectations

Fusion’s critical milestones: The path to viable fusion energy requires clearing three significant hurdles.

• Scientific breakeven (Q>1): The National Ignition Facility achieved this milestone in December 2022, but with extremely brief reaction times
• Engineering breakeven: No project has yet achieved this crucial milestone
• Commercial breakeven: This remains the most challenging goal due to practical and economic constraints

Technical challenges and limitations: Several substantial obstacles stand in the way of fusion power becoming commercially viable.

• The scarcity of tritium fuel poses a significant challenge, as it’s primarily produced as a byproduct of nuclear fission
• Regulatory frameworks for fusion reactors remain incomplete
• Cost competitiveness against existing energy sources appears unlikely based on current research

Private sector developments: Despite the challenges, fusion research continues to attract private investment and innovation.

• Approximately 45 private companies are currently pursuing fusion technology
• Commonwealth Fusion Systems leads the pack with its SPARC reactor, aiming to achieve Q>1 by 2027
• High-temperature superconducting magnets could enable significant improvements in reactor efficiency and size

Looking ahead – practical considerations: While fusion development continues, fission technology presents a more immediate solution to growing energy demands.

• The commercialization timeline for fusion could extend 15 years beyond engineering breakeven
• Fission technology offers a proven, commercially viable path to support net-zero emissions goals by 2050
• Fusion may benefit from streamlined regulations due to lower proliferation risks, potentially accelerating future development

Market implications and outlook: The immediate future of nuclear power likely belongs to fission technology, though fusion development warrants continued attention.

• The established nature of fission technology makes it better positioned to meet near-term clean energy goals
• Fusion technology, while promising, requires significant technological breakthroughs and regulatory development before commercial viability
• The success of either technology will have significant implications for the global transition to clean energy