Accelerating the development of new solar absorbers
The replacement of fossil fuels is an imperative in addressing the challenges of climate change. Generating electricity from renewable sources such as wind and the sun is a major part of this. The UK is currently being urged to target 65% of all electricity generation being from renewables by 2030 and it is already committed to reducing emissions by 100% from 1990 levels – the so-called “Net Zero” target. Similar targets exist for many other countries. Part of this will be achieved by a huge expansion in solar power. Expansion from the current ~0.5 terawatts to 10 terawatts is thought to be possible globally by 2030, but requires a 30% year-on-year expansion. The market is currently dominated by silicon solar cells (95% market share), but thin film solar using cadmium telluride is cheaper and has a much shorter energy payback time. Due to the lack of abundance of tellurium in the earth, research is underway to find alternative, but ultimately as effective, thin film materials for solar cells.
In March 2021, a paper titled: “Accelerating the development of new solar absorbers by photoemission characterization coupled with density functional theory” was published in the Institute of Physics’ publication Journal of Physics: Energy. The lead and senior author of this paper is Dr Elisabetta Arca, a Project Scientist in Energy Technologies at Lawrence Berkeley National Laboratory (LBNL), USA. The paper was co-written by Robert Kostecki of LBNL, Tim Veal from the Condensed Matter Physics research cluster and Stephenson Institute for Renewable Energy at Liverpool and David Scanlon from Department of Chemistry, University College London.
The paper provides an overview of the use of photoemission characterization methods and theoretical approaches to accelerate the transfer of emerging solar absorbers into efficient photovoltaic devices. In particular, it is necessary to develop new approaches and techniques that can accelerate decision-making steps on whether further research on a particular material is worth pursuing or not. Development of the most promising candidate materials into highly efficient and stable solar cells is still, in almost all cases, a lengthy process. The ultimate aim is the development of materials containing earth-abundant elements that can contribute to the production of solar cells for tera-watt-scale energy generation.