SBIR Phase I: Ultra-Thin Silicon Solar Cells for Lightweight Flexible High-Efficiency Photovoltaic Modules

这个小企业创新研究（SBIR）第一阶段项目的更广泛影响将是支持社会对更高采用清洁可再生能源的需求。 该项目将实现的新型高效，轻质和薄型光伏组件将是工厂与商业和工业（C I）建筑屋顶材料集成的理想选择。 这将解决一半的美国C I屋顶市场（低坡度金属屋顶），由于重量限制，风荷载效应和其他因素，现有光伏组件的服务很差。 此外，通过减少安装材料和劳动力，以及简化系统设计和许可等，它将使C I屋顶光伏系统的总成本降低40%。这种颠覆性创新可以将C I光伏系统（目前美国三大光伏市场中最小的一个）转变为美国太阳能增长的关键驱动力。 这种光伏组件产品非常适合美国制造。 SBIR第一阶段拟议项目将允许首次探索吸收层厚度远低于40微米的硅异质结太阳能电池。 更高厚度的硅异质结太阳能电池已经达到了超过26.5%的世界纪录效率。 对于该项目所针对的超薄硅设计，理论预测开路电压（Voc）至少为780 mV，远远超过任何硅太阳能电池的电流记录。 高Voc将降低光伏系统的电阻损耗，并最大限度地减少高工作温度引起的系统性能下降。 关于太阳能晶片技术，这将是实现硅异质结太阳能电池的新的无切口方法，导致新型的稳健的柔性薄光伏模块，与当前的柔性薄膜光伏选项相比具有高得多的效率、上级可靠性和低成本。 在第一阶段项目中，我们的目标是Voc至少为720 mV。 我们还将研究优化硅异质结太阳能电池的后反射器设计，以最大限度地提高薄硅吸收层的光吸收。最后，我们将确定一个详细的路径前进到24%的效率为这个太阳能电池的设计。这个奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的智力价值和更广泛的影响审查标准。

The broader impact of this Small Business Innovation Research (SBIR) Phase I project will be to support the societal need for higher adoption of clean renewable energy. The new kind of high-efficiency, lightweight and thin photovoltaic modules that will be enabled by this project will be ideal for integration at the factory with roofing materials for Commercial and Industrial (C&I) buildings. This will address half of the U.S. C&I rooftop market (low-slope metal roofs) that is poorly served by existing photovoltaic modules due to weight limits, wind-loading effects and other factors. In addition, it will drop total C&I rooftop photovoltaic system cost by up to 40% through reduction of installation materials and labor, as well as simplification of system design, permitting, etc. This disruptive innovation can turn C&I photovoltaic systems--today the smallest of the 3 major U.S. photovoltaic market segments--into a key driver for US solar growth. This photovoltaic module product is ideally suited for US manufacturing. The SBIR Phase I proposed project will allow the first ever exploration of Silicon heterojunction solar cells with absorber thickness substantially below 40 microns. Higher thickness silicon heterojunction solar cells have already achieved world record efficiency of over 26.5%. For the ultra-thin silicon design targeted by this project, theory predicts an open circuit voltage (Voc) of at least 780mV, well in excess of current records for any silicon solar cell. High Voc will reduce photovoltaic system resistive losses as well as minimizing system performance degradation from high operating temperatures. With respect to solar wafer technology, this would be a new kerfless approach to realizing silicon heterojunction solar cells, leading to a new type of robust flexible thin photovoltaic module, with much higher efficiency, superior reliability, and lower cost compared to current flexible thin film photovoltaic options. In this Phase I project we will target Voc of at least 720mV. We will also investigate optimizing the rear reflector design for silicon heterojunction solar cells, to maximize light absorption in the thin silicon absorber layer. Finally, we will identify a detailed path forward to 24% efficiency for this solar cell design.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.