Top Tech Startups in San Francisco, CA in 2027

Reunion is the leading platform for clean energy tax credits and compliance. Since 2024, we have worked with major corporations to invest over $7 billion in clean energy projects, including some of the industry's largest tax credit transactions. We are a fast-growing and profitable company, and our expert 25-person team knows how to get things done and loves to move fast! Our founders, Billy Lee and Andy Moon, are second-time entrepreneurs and were early pioneers in solar tax equity and project finance. We have recruited an experienced team of early executives from SunEdison, SolarCity, Tesla, GoodLeap, and other leading clean energy companies. We have built a strong company culture which values collaboration and speed… while still having fun. In 2025, we launched Reunion PWA, a software solution that helps developers comply with prevailing wage and apprenticeship (PWA) requirements to unlock the full value of clean energy tax credits. Reunion PWA is rapidly gaining traction in the market, and we’re growing our team to accelerate adoption and expand to additional compliance offerings. Join us in the fight against climate change by helping renewable energy developers build faster!

Sahova is building the first AI-native operating system for construction. We believe the future of construction isn't another project management tool—it's an intelligent operating system that understands every project, document, conversation, and workflow. Our mission is to simplify and advance how builders and contractors run their businesses through AI.

C5R is building facilities that connect frontier AI to the physical world. We believe this connection is a force for good in expanding humanity's scientific discovery.

We help people turn memories into personalized figurines for meaningful gifting