
By Hannah Long
On a recent weekend, Berkeley inventor Dan Freschl could be found climbing the boulders of Yosemite while testing the rechargeable, environmentally friendly headlamp he has designed. The headlamp is the signature product of Bosavi LLC, the outdoor equipment company that Freschl founded in 2010.
Freschl’s love for the outdoors began when, as a teenager, he participated in a 22-day mountaineering and rafting trip with the Outward Bound program. After college, he worked as an engineer creating batteries for products such as pacemakers and implantable defibrillators. That work conflicted with his love for nature, however.
“When I worked for a huge corporation with about 20,000 employees, I saw how much we wasted, how much equipment we bought and then threw out, and how unhappy the people working there were.”
Freschl found inspiration on a camping trip to Joshua Tree National Park. Looking at his headlamp he realized “it was so disposable and cheap. I began to think about the batteries that could really make a better headlamp.”

Thus, the self-described “tech nerd and environmentalist,” quit his job and set out on a quest to revolutionize the headlamp.
Freschl now works out of a space at the Joshua Tree Artisans’ Collective in West Berkeley, which houses artists, designers, and other inventors. He moved to North Berkeley with his wife in 2007. They were attracted to the area’s great food and art, as well as the resources that UC Berkeley provides.
Freschl’s extensive knowledge of batteries allowed him to create the exact specifications for the lithium polymer batteries for the lamp.
“I requested the dimensions, voltage, and size, which allowed me to control the power and capacity of the battery,” he says. This particular design is much more efficient than the typical AAA battery and uses almost 100% of the capability of the battery. “This, of course, allows for more light output with a smaller size headlamp,” Freschl explains.
Efficiency has been one of Freschl’s primary goals throughout the project. He bought his first piece of manufacturing equipment very inexpensively on eBay, and used it to make prototypes out of wood gathered from a local woodshop. By using little money, Freschl notes, “I also made little waste.”
Another environmental touch is that Bosavi’s packaging transforms into an origami lantern that connects to the headlamp, again reducing waste.
Now ready to begin production, Freschl has turned to Kickstarter to gather funds. This site allows inventors to promote their projects and attract investors. In return, contributors receive the product once manufacturing is completed. Freschl has already been promised $30,000 of the $40,000 he needs to begin production. His deadline is just two days’ away. He hopes to begin distributing the headlamp to Bay Area outdoor stores and rockclimbing gyms later this summer.
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