Meet the Researcher: Mahati Chintapalli Showcases a Novel Technology to Improve Energy Efficiency in Windows

Mahati Chintapalli is a PARC researcher specializing in nanostructured and polymer-based materials for energy applications.

Approximately 30% of buildings in the U.S. have single-pane windows. Although they are inexpensive, single-pane windows are poor thermal insulators and lead to low energy efficiency and discomfort for building occupants. Double- and triple-pane windows are more energy efficient, however they come with high material and installation costs.

At this year’s ARPA-E Energy Innovation Summit, PARC Researcher Mahati Chintapalli showcased a scalable, low-cost thermal barrier that is designed to improve the insulation in single-pane windows. We asked Mahati to tell us more about this novel technology.

Mahati, can you describe the technology behind this thermal window barrier?

We are developing a highly porous and transparent polymer aerogel, which forms a thermally insulating layer that we laminate to a piece of glass with a low-emissivity coating.

The aerogel, paired with the low-emissivity coating, demonstrates improved thermal performance over single-pane windows, and is projected to result in significant energy savings, including a reduction in heating costs. The slim and lightweight profile of our aerogel and low-emissivity glass pane makes it easy to install within existing single-pane window sashes.

What was the driving force behind the single-pane window retrofit project?

Xerox invented a technology that was pioneered back in the ‘90s for making polymers using a very controlled process. Researchers at PARC, including Gabriel Iftime, wanted to apply that same technique to make porous materials for single-pane windows. Also, our lab was already working on self-cooling paint, another type of thermal management technology which dovetailed well with the single-pane window project.

Is there anything comparable to this aerogel technology currently on the market?

No. What does exist is a commercial low-emissivity glass. Our aerogel improves on the thermal performance of low-emissivity glass. Other technologies that exist are window insulation films and storm windows, but these alter the appearance of the window, unlike our aerogel-based technology.

How does the performance of the aerogel compare to double-pane windows?

The performance of our aerogel in terms of U-Factor (i.e., rate of heat loss) is on par with that of double-pane windows.

Are there any other applications for this aerogel technology?

Yes, the aerogel’s scalability, high transparency, porosity, and thermal properties make it a good candidate for insulating skylights and storm windows, as well as double- or triple-pane windows that are being used in new construction. Outside of building technologies, there may be many other new applications, as it is unique for a material to be both transparent and porous.

Are you working on any other projects in the energy efficiency space at the moment?

Yes, I am also contributing to a new technology to improve indoor air quality. Specifically, we are working on the removal of carbon dioxide, which is not addressed with air filters and other technologies currently on the market. People don’t often think about carbon dioxide as an indoor air pollutant. Improper air ventilation can cause a build-up of carbon dioxide which can reduce cognitive performance.

We’re exploring the selective removal of carbon dioxide using an electrochemical process. This would reduce the amount of air exchanges that would need to take place, thereby creating a more energy efficient HVAC system.

What do you enjoy most about working at PARC?

What I enjoy most is what drew me to PARC in the first place – working with brilliant and supportive colleagues and having the opportunity to develop novel energy savings solutions that make a positive impact on our environment.  PARC is a highly collaborative workplace!  I enjoy working with the amazing aerogel team, including Stephen Meckler, Gabriel Iftime, Austin Wei, and Jessy Rivest.

When you’re not working in the lab, how do you like to spend your time?

I play the fiddle and I’m currently learning how to play the banjo.  Sometimes, you’ll catch me playing fiddle with fellow colleagues at PARC. I also enjoy hiking and I recently became interested in mushroom foraging.

To learn more about the thermal barrier for single-pane window retrofits, download the information sheet.