The Impact of Adjustments to Time-of-Use Tariff Policies on the Usage Behaviour of New Energy Vehicle Charging Infrastructure

Abstract

Driven by the strategy for green and low-carbon transition, the development of charging infrastructure for new energy vehicles faces the coupled challenge of fluctuating demand and the optimisation of resource allocation. This paper utilises the time-of-use tariff policy adjustment implemented by the Jibei Power Grid on 1 January 2026 as a natural experiment. Questionnaire surveys were conducted at two time points—before and after the policy announcement—and Structural Equation Modelling (SEM) was employed to empirically analyse the mechanisms through which the policy adjustment influences the charging behaviour of new energy vehicle users. Based on the Technology Acceptance Model (TAM) and demand response theory, the study constructs a conceptual model comprising five latent variables: perceived ease of use, perceived usefulness, policy awareness, subjective norms, and willingness to adjust charging behaviour. A total of 669 valid questionnaires were collected from the two rounds of surveys. Data tests indicated that the data met the normality assumption, with no severe common method bias. Harman’s single-factor variance explained was 29.8%, and all VIF values in the multicollinearity diagnostics were less than 3; furthermore, the model used in this study outperformed competing models. The study found that: (1) The policy adjustment significantly enhanced users’ perceived sensitivity to electricity price signals, with the mean willingness to adjust charging behaviour rising from 3.18 to 4.09, an increase of 28.6%; (2) Policy awareness is the most critical factor influencing the willingness to adjust, with a path coefficient of 0.428 (p < 0.001), and it plays a significant mediating role between perceived usefulness and the willingness to adjust, accounting for 34.9% of the indirect effect; (3) Perceived usefulness (0.347) and subjective norms (0.186) have a significant positive impact on the willingness to adjust, whilst perceived ease of use exhibits a slight negative impact (-0.124); (4) Multi-group analysis indicates that the path coefficients for perceived usefulness and policy awareness significantly increased following the policy announcement; (5) There is a marked disparity between users’ willingness to adjust and the availability of charging facilities during specific time slots: during the winter off-peak period (12:00–15:00), the availability of charging points in office areas was only 31.8%, whilst during the summer peak period (18:00–21:00), the congestion rate of residential charging points reached 67.2%. This paper provides theoretical grounds and empirical support for the refined design of time-of-use pricing policies and the coordinated optimisation of new energy vehicle charging infrastructure.