Energy losses through windows account for up to 30% of a building’s heating and cooling energy, and cost building owners $200B annually. Products such as triple panes and vacuum insulated glass (VIGs) offer improved performance compared to standard double pane windows but introduce new challenges including cost, thickness, weight, embodied carbon, and aesthetics. Therefore, novel IGU designs are still necessary to make windows more energy-efficient while reducing costs to consumers. While many industry professionals have explored triples, thin triples, and VIGs, many have never seen aerogel-insulated windows despite their potential to radically improve window U-factors.
In their 2022 report “Pathway to Zero Energy Windows” the National Renewable Energy Laboratory (NREL) identified aerogels as a pathway to achieve long-term window performance goals. Aerogels are a novel class of nanoporous materials that exhibit record breaking thermal insulating properties, making them excellent candidates for next-generation high-performance glazing. Radical advances in aerogel technologies have put them on the cusp of commercialization. Barriers still exist, however, that prevent wide-spread adoption of these materials for glazing applications, including material durability, variable transparency, and production costs.
Herein, we present a review on the use of aerogels for high performance glazing applications: the history and science behind aerogels, recent advances in transparent aerogel technology, and innovative strategies to integrate aerogels into the IGU production process.
We will explore recent demonstrations that use glass as a substrate for aerogel-coated glass capable of being used in IGU production, allowing for the measurement of U-Factors in various configurations and passing tests based on ASTM E2190 and AAMA 920. Additionally, we will explore unique material handling and logistical challenges associated with aerogels and how the IGU industry can help. Finally, we will share next steps in scaling aerogel manufacturing to enable the commercialization of transparent aerogels for the first time.