In the second installment of our Deep Dive: Missing Middle in Climate Tech series, created in partnership with Spring Lane Capital, we dive deeper into why the “missing middle” is not just a gap; it's a structural issue. We're joined by two of the sharpest minds in climate investing: Francis O’Sullivan, Managing Director at S2G Investments, and Rob Day, Co-Founder of Spring Lane Capital. Together, they explore how early-stage innovation and late-stage deployment are well funded, while the crucial middle phase of scaling is dangerously underserved.

We discuss why this gap exists, what solutions are emerging, and how investors are shifting their strategies to meet the moment. If you care about accelerating the climate transition, you’re going to want to listen to this.

What You’ll Learn

• Why the "missing middle" persists despite surging climate capital overall
• How venture capital models can distort scale-up potential
• What new capital strategies (like development expense financing) are emerging
• Why climate investing now enters a “third phase” of full-scale deployment
• How Rob and Francis are rethinking returns and risk for the climate transition

In today’s episode, we cover:

• [2:50 ] Francis' background and journey to S2G
• [4:36 ] Rob's career path in climate tech investing
• [6:30 ] Spring Lane Capital's founding and investment thesis
• [9:54 ] Discussion of the missing middle in climate finance
• [19:04 ] Structural challenges in climate investment
• [25:46 ] Organizational challenges for institutional investors
• [33:57 ] Concrete investment examples
• [41:37 ] Explanation of structured investment instruments
• [44:26 ] Historical context of climate investing

Resources Mentioned

• S2G Investments
• Spring Lane Capital
• World Resources Institute
• Invested in Climate - Missing Middle in Climate Tech Series: The Role of Family Offices with Spring Lane Capital & CREO, Ep #114
• S2G: 2023 Report - The Missing Middle: Capital Imbalances in the Energy Transition
• CREO: 2024 Report - Understanding the Climate Finance Gap
• Soluna

Connect with Us

• Jason Rissman
• Rob Day
• Francis O’Sullivan

Spring Lane Capital

• Website: https://springlanecapital.com/
• Linkedin: https://www.linkedin.com/company/springlanecapital/ 

S2G Investment 

• Website: https://www.s2ginvestments.com/
• Linkedin: https://www.linkedin.com/company/s2g-investments/

Invested in Climate

• Sign up for our Newsletter
• LinkedIn
• Instagram
• Youtube
• Bluesky

Have feedback or ideas for future episodes, events, or partnerships? Get in touch!