Resnick Institute


Solar Army Team Members

Solar Army Shines at Caltech

Spring 2016

Nestled in the South East corner of Crellin, there is a door adorned with the smiling face of Prof. Harry B. Gray welcoming you to the headquarters of the Caltech Solar Army. The Solar Army is the outreach program associated with the NSF Center for Chemical Innovation in Solar Fuels (CCI Solar), whose research focus is the sustainable conversion of solar energy into chemical fuels. Two of CCI Solar’s outreach projects are SEAL (Solar Energy Activities Laboratory) and HARPOON (Heterogeneous Anodes Rapidly Perused for Oxygen Overpotential Neutralization).

The scientific goal of these projects is to discover light-absorbing materials made of combinations of two to four metal oxides that can split water into hydrogen and oxygen. The number of potential combinations is almost endless, so that finding the right one is no easy venture. On the enormity of the task, Prof. Gray remarks “I can either use robots, or I can use kids, so I decided to use students because they are a lot more fun to work with than robots!” Thus, the Solar Army was created and now hundreds of eager high school kids meet weekly with Caltech graduate student and postdoc mentors to search for the elusive active combinations.

For many students, this is their first experience as real scientists, and the hope is that they will be encouraged to continue their studies in STEM fields. For many of the mentors, this is an opportunity to hone their teaching, advising and scientific communication skills. Resnick GS fellow Sam Johnson, is one such mentor. About her current group of Army Privates, Sam says “They’re always so excited about science… they remind me to be optimistic, curious and inquisitive.” Sam’s group is pretty new to the SEAL program, but through the use of the SKIES app (designed by a group of Caltech alumni) they can see what other groups are up to for inspiration.

The SKIES app provides a unique virtual and interactive workspace for the students to upload, share and store their data, as well as ask and answer questions. At the end of the school year, all the Southern California SEAL and HARPOON Brigades meet for a one-day conference at Caltech where they can share their discoveries through a poster or oral presentation and start planning for the year ahead.

Besides SEAL and HARPOON, the Caltech Solar Army arsenal contains a third project called Juice from Juice. Volunteers instruct middle and high school teachers how to build homemade solar cells that generate power via blackberry juice and sunlight. These types of solar cells are known as dye-sensitized solar cells (DSSC) and are significantly cheaper than the commercially available silicon solar cells.

The Juice from Juice workshops take place approximately four times a year, but the team also travels to special events like the annual San Diego Festival of Science and Engineering that was held in March this year. There they teamed up with UCSD Solar Army volunteers to teach kids and adults alike how to make and test their own DSSCs.

On the impact of the Solar Army, Michelle DeBoever, the Director of Education, Outreach, and Diversity for CCI Solar comments, “I think it's very important in several ways… This duality of outreach and professional development makes the Solar Army a valuable program for everyone involved.” In fact, the value is proven even off campus, as students have used their Solar Army projects to enter regional competitions. For example in 2015, a Solar Army student was a finalist in the prestigious Intel Science Talent Search, while my own SEAL brigade from Wallis Annenberg High School was runner up in the Youth Policy Institute Science Fair at CalSTate Northridge.

Prof. Gray’s smiling face also appears on the back of every volunteer’s Solar Army uniform, this time as a caricature of the famous Uncle Sam war poster beckoning for others to join the venture to power the planet with solar energy. The Solar Army is always enlisting new recruits to continue the revolutionary ongoing outreach projects at Caltech. There has got to be a fabulous catalyst out there that is yet to be discovered, and we need the troops to do it.

Want to enlist? Contact Michelle Hansen
Follow the missions on Twitter @thesolararmy and @CCISolar
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Sonja Francis

About the Author

Resnick Postdoctoral Scholar Sonja Francis works in the Lewis research group developing catalysts and product analysis methods for light driven and dark electrochemical carbon dioxide reduction.