Irvine student enters national STEM competition with her solution to food waste

Rhea Sreedhar Broadcom MASTERS
Rhea Sreedhar from Santiago Hills Elementary School is heading to Broadcom MASTERS, a national STEM competition. (Broadcom Foundation)

Households in the United States waste about a third of the food they purchase every year, according to a 2020 study from Pennsylvania State University

Rhea Sreedhar, a student at Santiago Hills Elementary School in Irvine, has a plan that could be a game-changer for reducing food waste and methane emissions, which is a contributor to global warming.

Rhea’s discovery is called the SmartM Detector. Using a Raspberry Pi, a miniature computer, she can code a solution to detect the rising methane levels in food, which in turn can notify her of wasted food. Her detector gained attention at the Irvine Unified School District’s annual Science Fair, where she was honored with the 2022 Broadcom Coding with Commitment Award.

Raspberry Pi SmartM Detector
Rhea Sreedhar connected four sensors to one computer.

The Broadcom Foundation seeks to inspire young scientists, engineers and innovators who will solve complex challenges of the future. Rhea will be competing in the national Broadcom MASTERS competition, which is considered the premier middle school science and engineering fair competition.

Rhea was inspired to create the SmartM Detector when her family, like so many others, sheltered in place during the pandemic. Not knowing how long they would have to stay inside and limit interactions with people outside of their home, the Sreedhar family stocked up on food. Unfortunately, some of the produce would rot before they could eat it. 

Rhea’s mother wished there was an alarm that would inform her that the food was rotten or was approaching its last few days of shelf life. During this time, she also noticed trucks stopping at a landfill located a few miles from her home to drop off waste.

Determined to find a solution, the elementary school student studied how carbon dioxide and methane impacted food. She also turned to YouTube for tutorials to guide her in using her new computer. 

“I knew I needed a sensor to monitor the fresh produce,” Rhea said. “After researching, I noticed that only using a visual monitoring system was not enough. I implemented a different element and decided to work with gas sensors.”

SmartM Detector final design
After creating a prototype, this was Rhea Sreedhar’s final design for the SmartM Detector.

Rhea first showcased her project at her school district’s fair and advanced in March to the 67th annual Orange County Science and Engineering Fair, where she earned second place in the electricity and electronics category.

“I want to be a problem solver — using computing and my love for science to keep innovating and creating new products and solutions,” Rhea shared. “The Raspberry Pi gave me the confidence that I can build something usable with both software and hardware that can help families around the world.”

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