Re-evaluating China’s New Energy Demonstration Cities with two-way fixed effects: A comment

China’s New Energy Demonstration City (NEDC) policy aims to address energy and environmental challenges. While two-way fixed effects (TWFE) regression is often used to evaluate such policies within difference-in-differences frameworks, it can lead to incorrect conclusions if unit and time effects are mis-specified. Re-evaluating the impact of the NEDC policy on energy poverty (EP), as studied in Ma et al. (2025), by correctly specifying unit-specific and time-specific effects, we find that: i) the parallel trends assumption fails, and ii) the previously reported impact on EP becomes economically and statistically insignificant. Whether NEDCs reduce EP therefore remains an open question.