B^3: Bench/Barrel/Boost

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It’s a bench! It’s a rain barrel! It’s a solar-powered cell phone charging station!

Meet B^3 (B-cubed): Bench/Barrel/Boost, a collaboration between Philadelphia Water, Public Workshop and 9th grade students at Science Leadership Academy’s Beeber campus.

Background and Research
Understanding why we have rain barrels in the first place was critical to the final design. Students learned about Green City, Clean Waters—Philadelphia Water’s 25-year plan to improve our rivers and streams by keeping stormwater runoff out of our sewers—and took a field trip to Fairmount Water Works to get more background on the city’s historic relationship with our water resources.

An early brainstorming session collected ideas about how the schoolyard could be improved and what amenities could accompany a structure built around a rain barrel.


After the initial brainstorm, Nick Nawa from Public Workshop sketched some design ideas. Key elements of the structure would include a shaded place to lounge and charge your phone. (Plans for a hammock, skate ramp, and/or tree house will have to wait.) In addition, the structure would collect stormwater from its canopy, providing water for nearby planter beds in the schoolyard.

Two solar panels are attached to the shade structure to collect sunlight and charge a cell phone attached through a USB port—one charger is for Android phones, the other for iPhones. Students soldered the circuit boards for the charger and helped place the panels in a sunny, southward-facing spot.


While rain barrels are typically connected to a building’s downspouts, the school has interior downspouts that are not accessible. Instead, the rain barrel will collect whatever water falls on B^3’s extended roof, which consists of a rubber liner with a drain connection to the barrel.

A prototype chair was made with a cardboard shade and a working solar charger. Then the students took to the makerspace to cut the pieces of the final product. Once all the pieces were cut, the final bench was assembled in the schoolyard, and the charger and rain barrel were attached.