To achieve net zero goal by 2050, enhancing energy efficiencies of thermal systems is crucial for advancing sustainable energy conversion and management in the built environment. Embedded cable/pipe thermal systems, as a key technology for heating and cooling systems within buildings and infrastructures, play a significant role in this context. This work presents a comprehensive steady-state theoretical framework to evaluate the thermal performance of embedded cable/pipe systems with different thermal management strategies, including asymmetric low-conductivity coating, high-conductivity surface layer, and independent insulation layer. A novel semi-analytical solution is developed for asymmetric coating strategy, incorporating the image method and thermal conductivity ratio between the substrate and coating material. It considers the effects of thermal conductivity and burial depth of the asymmetric coating materials. Extensive 2D steady-state numerical simulations were performed to validate the proposed solution with MAPE of 0.1042%. The comprehensive theoretical framework is used to evaluate not only the asymmetric coating, but also two other strategies: high thermal conductivity cement concrete as the surface layer and thermal insulation material as an independent layer below. The evaluation reveals that independent thermal insulation layers achieve the highest energy conservation with a relatively high thermal performance enhancement, while the asymmetric coating provides stable performance regardless of burial depth. The proposed framework supports configuration selection and optimization for applications such as pavement de-icing, snow melting, and near-surface energy harvesting, enabling more effective energy management in sustainable infrastructure. • Unified steady-state framework evaluates thermal performance of embedded cable/pipe heat transfer and energy management. • Novel semi-analytical solution for asymmetric coating with MAPE of 0.1042%. • Lower thermal conductivity of asymmetric coatings improves thermal performance. • Greater burial depth raises cable temperature while lengthening the characteristic response time ( T D ). • Independent insulation layer delivers highest performance enhancement.
Wang et al. (Sun,) studied this question.