Building integrated photovoltaics (BIPV) can contribute to the decarbonization of the buildings sector. However, existing tools for simulating their energy performance fail to accurately capture the complexity of the environment, design and integration of BIPV, limiting the ability of stakeholders to understand the potential of the technology. Most simulation tools have originally been developed for ground-mounted systems and thus overlook features of BIPV like complex shadings, diverse orientation of modules, or temperature fluctuations due to limited ventilation at the back of the modules. Yet, the capabilities and limitations of modelling tools for BIPV are not understood in detail. Now, Rebecca Jing Yang and colleagues — taking part in the International Energy Agency’s Photovoltaic Power Systems Technology Collaboration Programme — explore the potential of state-of-the-art tools for the modelling of urban layout, weather data and photovoltaic energy generation and compare the simulation results with energy yield data collected from an existing BIPV project.

The BIPV project is equipped with photovoltaic modules in three configurations: on the rooftop, on the façade, and on a canopy. The researchers find that all of the simulation tools return relatively accurate energy yield results for the rooftop system: this is likely because in this configuration the modules experience similar conditions to ground-mounted systems. Instead, the accuracy of most of the tools is low for the façade and canopy integrations. One of the key reasons is that the models do not account for complex shading effects and, for the façade integration, the vertical or curved orientation of the photovoltaic modules. Yang and team suggest that improved modelling of solar irradiance could help address these issues. Additionally, the research team identify other general areas for improvement such as the need for increased interoperability between the models and the input/output datasets as well as the availability of datasets. The findings offer guidance for developing simulation tools that capture the complexity of BIPV projects.

光伏建筑一体化（BIPV）有助于建筑行业的脱碳。然而，现有的能源绩效模拟工具无法准确捕捉 BIPV 环境、设计和集成的复杂性，限制了利益相关者了解该技术潜力的能力。大多数模拟工具最初是为地面安装系统开发的，因此忽略了 BIPV 的特征，例如复杂的阴影、模块的不同方向或由于模块背面通风有限而导致的温度波动。然而，BIPV 建模工具的功能和局限性尚未得到详细了解。现在，Rebecca Jing Yang 及其同事参加了国际能源署的光伏发电系统技术合作计划，探索最先进的工具在城市布局、天气数据和光伏发电建模方面的潜力，并比较了模拟结果与从现有 BIPV 项目收集的能源产量数据。

BIPV项目配备了三种配置的光伏组件：屋顶上、立面上和天篷上。研究人员发现，所有模拟工具都为屋顶系统返回相对准确的能量产量结果：这可能是因为在这种配置中，模块经历与地面安装系统相似的条件。相反，大多数工具对于外墙和顶篷集成的准确性都很低。关键原因之一是这些模型没有考虑复杂的遮阳效果，以及对于立面集成而言，光伏模块的垂直或弯曲方向。杨和团队建议改进太阳辐照度模型可以帮助解决这些问题。此外，研究团队还确定了其他需要改进的一般领域，例如需要增加模型和输入/输出数据集之间的互操作性以及数据集的可用性。研究结果为开发捕捉 BIPV 项目复杂性的模拟工具提供了指导。