Recent Publications

An Integrated AHP-SWOT Analysis on the Strategic Transition of Traditional Oil and Gas Companies to Fusion Energy in China

Chao Guo, Ya Yuan, Yongxin Zheng, Bo Wang, Xingang Li

China Petroleum Engineering and Construction Corporation, CNPC Capital Company Limited, Fusion Energy Technology Company Limited

Criteria for the economic viability of fusion power plants

D. G. Whyte, A. Lo, R. Bielajew, M. Hancock, R. Moeykens, G. Shaw

Rutherford Energy Ventures, Massachusetts Institute of Technology, Santa Fe Institute

Maintenance strategy, structural design, and site layout of the ST-E1 fusion power plant

J. Willis, K. Chandrasekhar, P. Cheema, J. England, V. Godhani, E. Guise, S.M. Levine, R. Pocock, A. Scott, A. Shone, et al.

Tokamak Energy Ltd, Remote Applications in Challenging Environments (RACE), Tokamak Energy Inc, Princeton Plasma Physics Laboratory

An effective fusion reactor maintenance scheme enables safe operations and short downtimes. This in turn leads to high availability, which is critical to the commercial viability of a power-producing plant. In tokamak-based fusion power plants, the chosen maintenance approach has a significant impact on the spatial design of the tokamak, as well as the surrounding infrastructure, and therefore needs to be considered from the outset. Tokamak Energy has developed a pre-concept design of a fusion power plant, ST-E1. This work describes the major drivers and constraints that have been considered, presents the tokamak architecture and chosen maintenance regime, and discusses how this enables the plant’s two-phased approach to demonstrating commercial operations. It also shows the implications for the design of other systems areas, in particular the machine structural arrangement and bioshield and hot cell layout. The reactor core segmentation and removal scheme replaces entire toroidal segments radially through a large vacuum port, along a single axis only. The result is a change-tolerant machine and plant layout that can accommodate the evolving designs of the tokamak.

Tokamak Energy’s pre-concept design for a fusion power plant: an overview of ST-E1

J. Willis, S.A.M. McNamara, E.N.J. Maartensson, J. Astbury, E. Yildirim, N. Hinton, C.L. Wilson, X. Zhang, J.W. Berkery, L. Baylor, et al.

Tokamak Energy Ltd, Princeton Plasma Physics Laboratory, Oak Ridge National Laboratory (ORNL), Idaho National Laboratory (INL), Savannah River National Laboratory (SRNL)

Climate change and rapidly rising energy demand, driven in part by artificial intelligence and data-centre growth, create an urgent need for stable, low-carbon, and abundant power. Fusion is a promising long-term solution, yet its commercialisation faces a fundamental paradox in today’s investment environment: pilot plants are essential to de-risk physics, engineering, and operations, but their limited lifetime energy output and high upfront costs make them difficult to finance. This paper presents Tokamak Energy’s response: ST-E1, a pre-concept design for a low-aspect-ratio tokamak power plant engineered specifically to overcome this challenge. ST-E1 is designed from the outset for phased operation—pilot and commercial phases, with an upgrade phase in between—with emphasis on commercial viability, maintainability, nuclear engineering, modularity, and upgradability. A key design principle is the deliberate separation of long-lived assets, such as the magnet cage and vacuum vessel, from replaceable in-vessel systems. This provides an attractive and credible investment approach to generate operational data and de-risk key technologies while preserving most capital-intensive assets for later commercial phases. The architecture supports continuous optimisation toward high net electric power (targeting 800–1000 MW net electric), a normalised capital expenditure of $ 12–14k/kW of net electric power, and high availability (targeting > 80 % ). A tokamak core with a 5 m major radius, aspect ratio of 2.3, and on-plasma axis toroidal field of 5.25 T was selected to meet these objectives. This paper summarises the ST-E1 design philosophy, principal features, and development methodology. It introduces a Focus Collection of 11 papers detailing the pre-concept design of the entire tokamak and corresponding plant.

Design scoping and systems modelling of ST-E1 using the PyTok power plant simulation code

C.L. Wilson, J. Astbury, M.J. Ginsberg, N. Hinton, E.N.J. Maartensson, S.A.M. McNamara, J. Willis, E. Yildirim

Tokamak Energy

To support the pre-concept design of Tokamak Energy’s (TEs) ST-E1 fusion power plant, we developed a new systems code, PyTok. PyTok codifies plasma physics and engineering constraints within a pure Python, object-oriented framework designed for rapid design iteration and exploration of the power-plant parameter space. The code base and its human- and machine-readable data structures enable coupling to external physics codes and data-analysis tools. Informed by TEs design philosophy and techno-economic analyses, the code was used to identify an initial reference design point for ST-E1. A commercially competitive fusion power plant is achievable with a tokamak power core of major radius 5.0 m, aspect ratio 1.9 ⩽ A ⩽ 2.3 and toroidal field 3.25 ⩽ B T ⩽ 5.25 T. The selected design point serves both as a pilot plant and as a commercially competitive reactor using the same permanent power core hardware, enabled by an in-vessel component upgrade phase. The commercial phase targets steady-state operation and a normalised capital expenditure of $12 000–15 000 per kW e , corresponding to a fusion power of 2.0–2.5 GW and a net electric power of 800–1000 MW.

A Method of (in)validating the Projected Levelized Cost of Electricity of Fusion Power

Adam Jackson