Ernst Theodor Sack is a Partner at Blue Bear Capital who specializes in AI-driven energy and climate software, focusing on startups that use AI to improve performance of existing infrastructure like solar farms, wind turbines, and industrial facilities rather than funding new hardware. He's known for backing founders with deep operational experience in energy field work and for his picks-and-shovels approach to climate investing, emphasizing practical AI tools for asset monitoring, predictive maintenance, and workflow optimization that can improve uptime and efficiency in large existing energy fleets.