Founded in 2009 by Josh Weiner, SepiSolar is an international solar-plus-energy storage design and engineering firm dedicated to serving the needs of solar EPCs, developers, and contractors.

In addition to our design services, SepiSolar provides technical and financial consulting services for solar and energy storage OEMs, developers, financiers, and policy makers.

Our Mission

To build a community of designers who care about solving tomorrow’s energy problems today.

These may seem like just a few words, but they’re truly meaningful for all of us here at SepiSolar. We genuinely care about our work, each other, our clients, and the community.

In fact, the community of designers that we’re building includes everyone. How people create and use energy guides our solutions for transitioning the world to renewables and a more intelligent grid.

Our Design Technology

SepiSolar has developed proprietary solar and storage design tools that create solar plan sets that achieve faster permitting and utility interconnection approvals, keeping projects on time. In fact, most of SepiSolar designs receive approval without revisions. Our technology is flexible, allowing Helioscope, Aurora, and other third-party proposal tools to be seamlessly incorporated to our full plan sets.


“Sepideh”—or “Sepi” for short—is the moment just before dawn. All of the sun’s power emerges out of that first ray of light. In the same way, the power that emerges from a solar -plus-storage project begins with design.

How we design reflects our core values of TRUE PV



We are honest and clear about what we say and do.



We are committed to delivering what we promise.



We work together for a common goal, for ourselves, customers, and advocates.



We are always learning, evolving, and sharing our knowledge and expertise with each other and our communities.



We care about each other, our customers, and everyone we touch.



We are always thinking about and preparing for the future.

We hope you’ll see these core values and mission in our team and in our future work together.

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