Quantum Dot Solar Windows to Power the Base of the Future

Air Force facilities, such as AFCEC, AFIMSC, and Base of the Future strongly rely on structural and energy resilience, mitigating power loss and increased stability of building materials. An interesting approach to achieve this goal is to use laminated glass solar windows for both increased structural stability and protection, as well as for covert power generation. Luminescent solar concentrators (LSC) represent a specific kind of solar window technology that enables window-integrated sunlight harvesting for electricity generation, in which an adjustable portion of light absorbed by the window “tint” is shifted to a specific color and directed towards small solar cells attached at the edges of the glass. Inherently, laminated glass LSC solar windows combine the safety benefits of laminated glass with solar energy generation in a single autonomous device. When combined with an embedded battery, the window can provide a steady uninterrupted supply of power for any local need, or be optimized for putting the energy into the local power grid. In its simplest implementation, the LSC is comprised of two panes of glass sandwiching a fluorescent polymer interlayer, with attached solar cells covering the perimeter of the window. Up to now, this concept was mostly developed for use in commercial buildings with a goal of optimizing performance and aesthetics relative to cost, and the company is deploying the first projects now. For Air Force or other DoD users, new priorities besides aesthetics and cost will be considered. Working prototypes with certified power conversion efficiency (PCE) up to ~4% and sizes up to 4 ft x 4 ft have been manufactured and tested using stable and non-toxic CuInS2/ZnS quantum dots (QDs) in the nanocomposite interlayer. One example of how this might be tailored for the Air Force is that multi-interlayer laminates have been shown to increase performance (ACS Appl. Energy Mater. 2020, 3, 8159-8163), which is expected to also improve structural rigidity, similar to bullet proof glass. This is readily achievable at scale due to availability of thin glass, for example, from Corning (eg, Gorilla glass), however is not considered economically viable in commercial uses due to the added costs of high performance glass. Additionally, the QDs can enable a wide range of different colors that could be designed to make the technology hidden, or covert, potentially even camouflaged in the near-infrared portions of the spectrum where night vision is sensitive. Another possibility would be to focus on the electrical system and design it for a specific Air Force need, including active sound dampening or powering sensors on the window. There are numerous uses cases that the technology could be adapted for within the Air Force. This phase I project seeks to identify those needs and collaborate with potential users on the technology development and initial deployment.