Modernization and industrialization have significantly increased energy consumption, causing environmental problems. Given that China is the largest energy user, the rise in building energy consumption necessitates clean energy alternatives. The purpose of this study is to summarize typical building models for primary and secondary schools in Hainan Province, and to use software to simulate and calculate the photovoltaic utilization potential of primary and secondary school buildings. In China, the government is usually the manager of primary and secondary schools, and due to their architectural characteristics, these buildings can be used to assess photovoltaic applications. The aim is to drive the application of photovoltaic systems in all types of buildings and promote urban energy reform. This study summarizes the types of primary and secondary school buildings in Hainan Province and analyzes them. It evaluates rooftop photovoltaic projects at the Second Middle School and the Siyuan School in Wanning City, Hainan Province, and uses PVsyst 7.2 software to assess the photovoltaic utilization potential. The results show that the optimal orientation in Hainan Province is south-facing, and the optimal inclination angle is 10° to 20°. The most favorable orientations of facade photovoltaic systems are 20° southeast or southwest. The longest dynamic investment payback period is approximately 15 years, and the environmental benefits are $0.012/kWh. The findings indicate significant potential for photovoltaic applications in primary and secondary school buildings. A combination of facade and rooftop photovoltaics can result in the zero-energy consumption of these buildings, reducing the pressure on urban power grids and achieving sustainable utilization.

The abundant land resources in rural areas have allowed for a rapid growth of the photovoltaic (PV) industry. However, the largescale construction of PV facilities has significantly impacted rural landscapes. This study systematically analyzed the visual impact of PV facilities on rural landscapes using the visual Q-method. By selecting images of PV facilities within rural natural, settlement, and production landscapes from different regions in China, visual perception scoring was conducted between experts and non-experts. Statistical analysis of the scoring results using PQMethod2.35 software identified five primary factors influencing the visual impact of PV facilities on rural landscapes: boundary integration, morphological innovation, color richness and coordination, multifunction, and scale. The findings indicate that PV facilities exert the most significant visual impact on rural natural landscapes, with a clear disparity in satisfaction. PV facilities negatively affect rural settlement landscapes, with dissatisfaction frequencies significantly exceeding satisfaction frequencies. However, their visual impact on rural production landscapes is negligible. The results will provide a reference for landscape planning and design of PV facilities in rural areas, supporting the sustainable development of PV facilities.

Under the guidance of the “dual carbon” goals, building energy efficiency policies are currently in a critical phase of transitioning from “dual controls on energy consumption” to “dual controls on carbon emissions.” Based on the theory of policy instruments, this paper takes 26 building energy efficiency policy documents issued in Tianjin from 1991 to 2025 as samples. By comprehensively applying content analysis and social network analysis, it systematically examines the evolutionary trajectory, combination characteristics, and structural relationships of policy instruments over the past three decades. This study reveals that Tianjin’s building energy efficiency policy system demonstrates a phased transformation trend—shifting from singular control to diversified incentives and from energy consumption constraints to integrated carbon emission management. The structure of policy instrument combinations has been progressively optimized; however, there remains room for improvement in terms of policy synergy, continuity, and the role of market mechanisms. Consequently, this paper proposes recommendations for optimizing local building energy efficiency policies across dimensions such as instrument coordination, temporal allocation, and mechanism innovation. These suggestions aim to enhance policy implementation effectiveness, accelerate the transition towards energy conservation and carbon reduction in the building sector, and provide empirical references for similar cities seeking to optimize their “dual carbon” policy frameworks.