Charge your phone with solar power as a first step to going green

The Window Solar Charger is a cheaper and less obtrusive way to go green.


Krystal Persaud, 30, created the Window Solar Charger for people who are in the beginner stages of going zero waste. 

Ben Fox Rubin/CNET

Krystal Persaud, dressed in a casual pink T-shirt and loose gray cardigan, greets me smiling in the Brooklyn coworking space A/D/O. She leads me to her wooden desk, located in a room that's well-equipped with everything from laser cutters to 3D printers. Placed alongside thin strips of bamboo and glue tubes is something that appears to be a picture frame.

But it doesn't display your family photos. The object is a project of Persaud's called the Window Solar Charger.

It's a thin cluster of black solar panels suspended in a transparent plastic sheet and framed in bamboo, designed to collect energy and store it in a lipstick-size battery that's found on the bottom edge of the device. It also houses a USB port, which can charge your phone, AirPods and other gadgets.

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The Window Solar Charger, which costs $149, is meant as a cost-effective alternative to rolling out roof solar panels, which can run you thousands of dollars, and more aesthetic for homes than bulkier solar panels made for camping. Its transparent design and minimal size are meant to make it less visually obtrusive in the home.


It takes between eight to 10 hours to fully charge, allowing for up to two phone charges.

Ben Fox Rubin/CNET

The charger is part of a broader push for sustainability. At a time when Apple says it's powered by 100% clean energy and Amazon plans to cut its carbon footprint in half by 2030, many consumers are also looking for ways to reduce their impact on the environment. Persaud sees her rig as an opportunity for people who are in the beginning stages of going zero-waste.

"I care about sustainability and I'm not going to … sacrifice convenience and style, as awful as it sounds," said Persaud, a 30-year-old native of Oakland, New Jersey. "A lot of people are like that too ... so why not bring it to them instead of asking them to change too much."

Persaud, who previously worked at the DIY- and education-focused startup LittleBits, is putting her charger on Kickstarter to raise money for her new company, Grouphug. Her crowdfunding campaign has already blown past its initial fundraising goal, exceeding her target of $10,000 set earlier this month and jumping to over $55,000. Visitors to the fundraiser can purchase the panel or donate $20 and receive an enamel pin.

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As we talked at her office last week, every few minutes her phone buzzes, signaling someone has donated to her campaign.

"While the emissions saved by charging a phone with solar power may be small, it's exciting to see new opportunities that allow people to play an active role in reducing their carbon footprints," said Amy Turner, executive director at the NYC Climate Action Alliance, a coalition dedicated to reducing greenhouse gas emissions. 

A passion for art and science

Persaud, the youngest of four sisters, was set on creating a distinct path for herself that didn't involve studying medicine like her siblings. She wanted a career that combined her passions in art and science. 

During her undergraduate years at Georgia Tech's School of Industrial Design, she tackled school projects with a sustainability aspect. When a professor assigned classwork to create a lamp, Persaud said the idea of a designer lamp was simply not challenging enough.

"I made a microbial fuel cell lamp … that harvests electricity from the bacteria in the soil when stuff decomposes and electrons are released," she said.

Following school and a few freelancing gigs, Persaud was introduced to Ayah Bdeir, founder of LittleBits, which sells kits of modular electronic building blocks for kids and adults to learn how to make simple gadgets. Throughout her six-and-a-half-year term at LittleBits, she rose from intern to senior director of product design, overseeing the timeline of different products and managing a team of designers.

And she remained true to her roots in sustainability. While she was working a full-time job, she participated in Maker Faire, an event that celebrates hands-on learning. At the event, she and a colleague created a phone charger that was powered by shaking it when you walked around. It wasn't a practical design, but it let her test out another idea in renewable energy.

She knew she wanted to return to sustainability and tech. So, last June, she left LittleBits.

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Persaud started working on an indoor composter but quickly abandoned that project because of its high costs. So she sent out an online survey to 100 friends and family, in which she asked what type of sustainable technology would attract them. Many of the results pointed to solar energy.

 From August to October last year, Persaud started sketching out her vision of a semi-transparent solar-powered product.

She created several prototypes until she arrived at her final design. By December, she had sold several early renditions at a local holiday fair but continued to work on the product.

This spring, prior to the Kickstarter launch, Persaud was able to see her vision of a transparent solar device at the New York Hall of Science with an immense cat-shaped solar panel. The installation served to teach young children how energy was extracted after rays of sunshine hit the device's circuit board. It also resembled the inner workings of her soon-to-be Window Solar Charger.

A product with layers of sustainability

The charger's design has several components that fit the theme of sustainability.

The slender frame is made of bamboo from Thailand and is polished with an organic mineral oil instead of a synthetic varnish. The clear plastic on which the panels are placed also contributes to the durability of the product. Dropping the charger shouldn't result in the panels cracking. It also takes between eight and 10 hours to fully charge, allowing for up to two phone charges.


The Window Solar Charger is a bridge between sustainability and technology. 

Ben Fox Rubin/CNET

"The panel is technically rated to last at least 25 years ... is at the 100% efficiency," Persaud said. "Even if you stepped on yours and accidentally cracked it, it would electrically still work."

She also hopes to work with a recycling company to allow customers to have an eco-friendly route to dispose of the product and potentially take advantage of carbon credits, offsetting the cost of production and shipping.

"I want the Kickstarter run to be as carbon-neutral as possible," she added.

Persaud's Kickstarter campaign ends in early July, but the chargers won't ship out until April of next year, and only in the US and Canada. But as she eyes the April shipment date, she hints at the possibility of a team expansion if all goes well.

For now Persaud's saving her energy to make sure her current product fares well among early adopters. 

"As you increase the quantity, the quality and finesse of [the product] should increase," she said. "Hopefully, next year I'll have all these pillars and start to scale in a more normal way."

A solar farm grows in Appalachian coal country

See all photos

Article updated on June 26, 2019 at 5:00 AM PDT

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Dhara Singh
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Dhara Singh CNET News Intern
Dhara Singh is one of CNET's summer interns and a student at the Columbia Graduate School of Journalism. She loves digging deep into the social issues that arise from everyday technology. Aside from wording around, you can catch her discussing Game of Thrones or on a random New York City adventure with her dSLR.
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