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A Harker attendee rides Green Team’s smoothie bike on Oct. 7 in the Auxiliary Gym. The club collaborated with the Harker Robotics team starting earlier this year to build zero-energy bike consisting of only upcycled materials.

Making a smoothie typically involves plugging in a powerful blender into an outlet, dumping in an assortment of fruits and pressing down on the lid. The blade instantly accelerates to thousands of revolutions per minute, and voilà, the contents turn into a consistent puree.

However, nearly 775 million people worldwide lack access to electricity and live without the everyday commodities that many have grown accustomed to. The upper school Green Team, working together with Harker Robotics, designed a bike capable of blending smoothies solely powered by pedaling. 

Talk for a collaboration between Green Team and Harker Robotics first began at the beginning of last year as a way to promote sustainability by upcycling materials. Green Team sourced all of the parts for the bike from thrift stores or bought them secondhand, demonstrating the possibilities of reusing resources.

“It was kind of a cool way to show how stuff has a longer life than we think it does,” Green Team co-president Siddhi Jain said. “You can repurpose things that you’d normally throw out. Obviously, some of it isn’t the most practical, but the point of [the bike] was to show that you can do zero waste things and sustainability can be fun.”

Although delays caused by the Robotics regular season pushed back the construction of the smoothie bike, Harker Robotics managed to build the bike in around one month’s time, finishing the design at the end of September.

During the engineering process, the team encountered significant obstacles. Firstly, the ovular shape of the gears in the bike resulted in an uneven feel as the rider pedaled. They eventually reduced this problem by designing a tensioner to prevent the bike chain from skipping on the gear.

Additionally, in order to achieve an RPM high enough to blend fruit, the team combined gears of various sizes to increase the number of blade rotations for every pedal cycle. Harker Robotics mechanical and machining co-director Akul Goyal (11), the primary lead for the smoothie bike, remarks on the project result.

“I think it’s a success because it addresses what the project was meant to do,” Akul said. “The smoothie bike gives you an idea of the amount of energy it takes to blend a smoothie and the effort that goes into it, and it also reminds you to be more carbon efficient.”

During Harker Day, Green Team used the bike to fundraise money for Good Karma Bikes, a nonprofit community bike shop. Selling smoothies blended through pedal power, they raised around 1,500 dollars. Going forward, the smoothie bike will star in Green Team’s Earth week activities after some mechanical improvements, alongside annual events like Earthchella and the Buy Better Boba sale.

Green Team advisor Diana Moss explained how initiatives like this highlight how young people, students in particular, can make a meaningful impact on the environment in their communities. 

“It’s really important for students to get behind climate solutions,” Moss said. “Let’s get off the fossil fuels; let’s get off those dependencies. I’m very hopeful that smart, young people will take the initiative to solve these problems.”