A research team in Korea has made a breakthrough in developing semi-transparent solar cells, making solar windows more of a possibility.
Scientists have been searching for ways to develop transparent or semi-transparent solar surfaces, which can be substituted for glass walls or windows in modern buildings, allowing more efficient harnessing of solar energy. This has been difficult because transparent solar cells reduce the efficiency of sunlight absorption, thus negatively impacting the amount of generated electricity. However, a Korean research team recently developed a semi-transparent solar cell which is highly efficient, and effective as a thermal mirror.
The Korean research team, which was led by Professor Nam-Gyu Park of Sungkyunkwan University and Professor Seunghyup Yoo of the Korea Advanced Institute of Science and Technology, used perovskites to achieve their breakthroughs. Solar cells are traditionally made out of crystalline silicon, which drops sharply in efficiency if made transparent. However, the perovskite-based solar cells are made out of hybrid organic-inorganic materials, and their efficiency has rapidly increased over the past few years.
Semi-transparent solar cells require the development of a transparent electrode for the top layer of the cell, that is compatible with photoactive material. The development team in Korea managed to develop a ‘top transparent electrode’ (TTE) that is compatible with perovskite based solar cells. The TTE developed by the team lets visible light pass through while also reflecting infrared rays. The average power conversion rate for the TTE utilizing cells was as high as 13.3%, which is impressive when considering that silicon solar cells can have up to 25% efficiency, but must be entirely opaque.
The research team believes that if the pervoskite solar cells make solar windows for buildings and automobiles a real possibility, which will not only generate electricity but also assist in heat management in indoor environments.