SH01@@Solar powered smart windows break 11% efficiency – enough to generate more than 80% of US electricity

The National Renewable Energy Laboratory, (NREL), has demonstrated a prototype of a solar powered smart window. The smart window lowers building temperatures by shifting from clear to opaque under strong sunlight. When the shift to opaque occurs, the solar prototype begins electricity production.

The prototypes tested reached up to 11.3% efficiency. The solar cell is based on the lab/headline favorite material perovskite.

One potential smart window feature is darkening of windows to minimize heat coming into a structure. Heating, cooling, and ventilation of commercial structures is up to 80% of their energy costs.

In the USA, up to 80% of residential units and 50% of commercial units, use some sort of ‘Low-E’ (low heat emission) glass. In this particular hardware, the smart darkening process begins the electricity producing magic when the glass becomes a solar cell via a heat driven chemical reaction.

The chemical reaction described:

Upon illumination, photothermal heating switches the absorber layer—composed of a metal halide perovskite-methylamine complex—from a transparent state (68% visible transmittance) to an absorbing, photovoltaic colored state (less than 3% visible transmittance) due to dissociation of methylamine. After cooling, the methylamine complex is re-formed, returning the absorber layer to the transparent state in which the device acts as a window to visible light.”