Imagine a smart window that could capture sunlight and not only lower building temperatures, but also convert it into electricity? Now, wouldn’t that be cool?
The National Renewable Energy Laboratory (NREL) has revealed a new prototype of a solar-powered smart window that has 11.3% efficiency rating and could also provide 80% of the United States’ electricity needs.
The smart window technology that is developed can keep the heat out of the buildings and also work as a solar panel and convert sunlight into energy.
The smart window can lower building temperatures whilst shifting from clear to opaque and also begin electricity production in the process. The windows are featured with a Low-E (low heat emission) glass that is used by 80% of residential units in the USA. Advanced materials such as perovskites, a calcium titanium oxide mineral and single-walled carbon nanotubes, microscopic structures with remarkable strength are the foundation of this new technology. And, the colour change (reversible) is attributed to methylamine (molecules).
How does the chemical reaction work?
The insulated windows have multiple layers of glass like the absorber layer that is composed of metal halide perovskite-methylamine complex. During illumination, the photothermal heating initiates the absorber layer from a transparent state to an absorbing, photovoltaic coloured state, due to methylamine dissociation. The methylamine complex gets re-formed, after cooling thus returning the absorber layer to the transparent state wherein the device works as a window to visible light.
The paper titled ‘Mechanism of switchable device degradation’ highlights the chemical issues that lead to the degradation. Lance Wheeler, a scientist at NREL, stated in this context that though there are many thermochromic technologies, nothing actually converts that energy into electricity.
The Road Ahead
The smart window has its challenges to balance the sunlight keeping it sufficient for the mental well-being and also using the advantage of sunlight to produce electricity. Meanwhile, the technology could also be integrated into buildings, vehicles, and more.