742: Mosaic’s Journey to $15 Billion in Residential Solar Loans with Co-founder & Executive Chair, Billy Parish

When I started SunCast, it seemed like there were lots of “Pioneers”; I even did a series focused on Solar Pioneers.  That was 9 yars ago.  Nowadays, most people are following playbooks others have written, and true pioneers are few-and-far-between. But I do still get to bring real pioneers on the show.  Today’s guest has taken all 9 years to lock down, despite having first met Billy Parish in 2011, fully 4 yrs before I started SunCast! Good things come to those who wait.  And you’ve waited a long time for this story, as Never Before Told…The Billy Parish, Mosaic Anthology!

How does a social activist unexpectedly become a pioneer in solar financing, helping shape the industry while funding over $15 billion in residential solar loans?

Billy Parish, Co-founder and Executive Chairman of Mosaic, turned his passion for activism into a mission to make solar power accessible and affordable for millions of homeowners. Before founding Mosaic, Parish was a youth activist and impatient budding entrepreneur.  His first real breakout success was Energy Action Coalition, a youth-driven climate movement, which laid the foundation for his work in clean energy. His work brought him international acclaim, including being a Rolling Stone Climate Hero and Mother Jones Student Activist of the Year, all while he was “taking time off” from Yale!  When he turned his focus to solving solar energy’s finance & scalability problem, little did he realize it’d turn into a nearly 2-decade journey, much naysaying, and a few ‘pivots’. Nevertheless, through Mosaic's innovative financing models, they have empowered thousands of contractors and funded billions in residential solar loans - and in many ways, it seems they’re just getting started.

Billy traveled from his residence in Berkeley, CA, to Washington, DC, to sit down with Nico and share his journey, insights, and Mosaic’s standout innovations. One of Mosaic’s major achievements includes launching the first 20-year solar loan product and a fully digital point-of-sale system credit application process that revolutionizes solar financing. Parish explains his "theory of change," focusing on making clean energy accessible to all through engagement and equity—a journey that earned him a feature in Rolling Stone for his climate leadership.

Expect to learn:

• Billy Parish’s blend of activism and entrepreneurship as a driving force for opening solar as an accessible asset class to millions.
• Mosaic’s shift from crowdfunding to institutional investors, scaling to $15 billion in loans.
• Mosaic’s innovations in digital infrastructure that makes solar financing fast and easy for homeowners.
• Why U.S. solar installations take months, and how Mosaic is working to cut delays.
• How tools like SolarAPP can save thousands per project by speeding up solar permitting.

Listen now as Nico finally gets to deeply connect with one of Solar’s widely-accepted iconic pioneers, Billy Parish.

If you want to connect with today's guest, you’ll find links to his contact info in the show notes on the blog at https://mysuncast.com/suncast-episodes/.

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