Transparent organic photovoltaics (TPV) can harvest energy from the near-infrared (NIR) and ultraviolet region of the solar spectrum and could be used in new applications such as windows. In addition to producing electricity, the transparent organic solar cell absorbs in the NIR region and could reduce the cooling energy demand of buildings during summer. Organic photovoltaic (OPV) is an emerging technology, developed mostly to replace fossil fuel energy, aimed to reduce greenhouse gases emissions. As OPV technology is reaching commercialization, it is essential to quantify its environmental impacts and ensure that new issues are not created. Life cycle assessment (LCA) is often used to compare energy technologies and identify environmental concerns, but this process is challenging for emerging technologies due to lack of inventory data. To guide future transparent OPV development, this work (1) demonstrates a new iterative methodology to evaluate and guide OPV material manufacturing that combines LCA and green chemistry approaches, (2) evaluates the energy saving from organic TPV in window and skylight applications in various cities, and (3) assesses the impact of organic TPV on urban heat island effect.The methodology was used to identify “hotspots,” which correspond to the processes that have the highest impact for chloroaluminum phthalocyanine (ClAlPc) manufacturing. An optimized process that reduces the environmental impact by 3%, the cost by 9% and chemicals hazard by 23% compared to the current process was demonstrated. The impact of TPV during the use phase was studied using ClAlPc based devices in window application. The building energy performance was shown to improve by up to 20 % due to heating and cooling energy saving. The energy saving varies with climate since NIR absorption by TPV in a window is more efficient in a warmer climate. The use of TPV in the window application in an urban area could further reduce the energy demand of buildings. The net energy saving by the TPV application in the urban area was calculated to be higher than in rural area by up to 2 GJ per month.
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