The “Non-Electric and Cogeneration Applications of Nuclear Energy” Working Group (NECA WG) was formed in 2024 to advance knowledge and access to energy system design, analysis, and optimisation tools that may allow decision makers to find optimal energy system solutions for different socio-economic and geographical contexts. This working group builds upon the work carried by the concluded GIF Non-Electric Applications of Nuclear Heat (NEANH TF, 2021-2024).