Climate change is the environmental challenge of our generation. In 2018, the Intergovernmental Panel on Climate Change (IPCC) released a special report on the impacts of global warming of 1.5°C above pre-industrial level. This reports clearly pronounced the climate related risk if global warming exceeds 1.5°C before 2100, with many impacts being long lasting irreversible damage to the ecosystem.
Limiting global warming to 1.5°C with no or limited overshoot requires “rapid and far-reaching transitions in energy, land, urban and infrastructure (including transport and buildings), and industrial systems.” In energy systems, the special report assessed mitigation pathways consistent with limiting warming to 1.5°C. Amongst all these pathways, renewable energy supply is projected to take up to 70-85% of the primary energy production, in combination of large decline of fossil fuel usage in primary energy supply (-39 to -77% for oil, -13% to -62% for natural gas, and zero coal consumption in some analyses). The figure below speaks to this.
Figure 1: Projection of energy production by fuel types, as proposed in the mitigation pathways studied in the IPCC special report (chapter 2). The consensus among reports was that solar power will play a significant role in the future.
Solar power is a key ingredient in the renewable energy portfolio. Photovoltaic (PV) solar panels, the most common solar energy deployment, come with a unique set of complications which has limited their widespread use. Glass is often used on the top surface of the PV panel, allowing light to pass through while protecting the semiconductor wafer (cells). PV glass sheets are typically coated with a quarter wavelength thickness antireflection layer that reduces reflection losses at the air/glass interface. However, this coating does not provide for antireflection across a broad range of wavelengths or wide range of incidence angles. In addition, solar panels are subject to soiling which degrades their performance.
Figure 2: Graphic representation of a standard PV cell design with glass substrate. Heavy soiling (accumulation of dust or particulate matter on the transparent substrate) can impede transmission of light and degrade solar cell efficiency.
We partner with the Laboratory of Advanced Material at Pittsburgh to develop a new generation of nanostructured glass that is dust resistant without sacrificing optical performance. In this project, we deploy a new Bayesian optimization strategy to efficiently search for the fabrication of nanostructured glass that can carefully balance multiple properties. In a following post, we demonstrate the new nanostructured glass, and we detail how Bayesian optimization can help quickly identify the fabrication process of this device.