Valuing maintenance strategies for fusion plants as part of a future electricity grid

TL;DR

This paper evaluates how different maintenance strategies impact the economic value of fusion power plants within a future decarbonized US electricity grid, highlighting the importance of seasonality and maintenance timing.

Contribution

It introduces a detailed analysis of maintenance scheduling effects on fusion plant economics considering seasonal variations and component replacement strategies.

Findings

Seasonality can increase plant value by up to 15%.

Shorter, spread-out maintenance blocks can outperform longer outages.

Optimal maintenance timing depends on electricity demand and supply patterns.

Abstract

Scheduled maintenance is likely to be lengthy and therefore consequential for the economics of fusion power plants. The maintenance strategy that maximizes the economic value of a plant depends on internal factors such as the cost and durability of the replaceable components, the frequency and duration of the maintenance blocks, and the external factors of the electricity system in which the plant operates. This paper examines the value of fusion power plants with various maintenance properties in a decarbonized United States Eastern Interconnection circa 2050. Seasonal variations in electricity supply and demand mean that certain times of year, particularly spring to early summer, are best for scheduled maintenance. Seasonality has two important consequences. First, the value of a plant can be 15% higher than what one would naively expect if value were directly proportional to its availability. Second, in some cases, replacing fractions of a component in shorter maintenance blocks spread over multiple years is better than replacing it all at once during a longer outage, even through the overall availability of the plant is lower in the former scenario.