Evaluation of the influence of the urban context on the available solar radiation for energy generation

Abstract In this work a methodology was developed to evaluate the influence of urban context on the usable solar radiation for energy generation through photovoltaic modules on building envelope. The methodology is based on computer simulations using the programs Diva-for-Rhino and EnergyPlus. Two Brazilian cities with different climate were selected for the study: Florianopolis and Fortaleza. Different urban contexts were defined considering buildings with uniform height (Uniform Context) and random height (Random Context). Through the analysis of solar radiation on the building envelope the influence of shading on energy generation for the different office building types was determined. In addition, strategies for PV application on building envelope through the detailed analysis of available solar radiation were developed. The results showed that within an uniform context PV modules are a good option for energy generation. For buildings up to 6 floors enough energy can be generated to achieve an equalized annual energy balance. For this context the area with highest potential for energy generation is the roof. For the random contexts the facades of the high-rise buildings are an interesting option for PV application as well.

摘要 本研究开发了一套评估方法，用于量化城市环境对建筑围护结构上光伏组件发电可用太阳辐射的影响。该方法依托Diva-for-Rhino与EnergyPlus两款软件开展计算机模拟实验。本研究选取两座气候特征迥异的巴西城市作为研究对象：弗洛里亚诺波利斯与福塔莱萨。研究设定了两类典型城市环境：建筑高度统一的均匀城市环境（Uniform Context），以及建筑高度随机分布的随机城市环境（Random Context）。通过分析建筑围护结构表面的太阳辐射分布，明确了不同高度办公建筑的遮阳效应对光伏发电量的影响规律。此外，通过对可用太阳辐射资源的详细研判，提出了建筑围护结构光伏应用的优化策略。研究结果显示：在均匀城市环境中，光伏组件具备优异的发电应用价值；对于6层及以下的建筑，其年发电量可实现年度能源收支平衡，且该环境下发电潜力最高的区域为建筑屋顶。而在随机城市环境中，高层建筑的外立面同样是光伏应用的优质可选场景。