Participated · Seed · Aug 2026

Mafix develops a mineral conversion process that transforms abundant silicate rocks into silicon-based fertilizers that weather within a single growing season, releasing nutrients and removing CO2 as stable bicarbonate. The company is commercializing a first-generation climate-smart fertilizer and plans a commercial demonstration to produce 1,000 tons of product. Mafix’s manufacturing approach repurposes spare capacity in existing cement kilns to avoid building new facilities and to access established logistics hubs. The technology was developed at Stanford University and the company was co-founded by Jade Marcus and Dr. Matthew Kanan. Mafix raised $5.4 million in a pre-seed round to fund the demonstration, further R&D across additional feedstocks, and development of next-generation mineral products and applications.

Participated · Series C · Jul 2026

Antora Energy develops and deploys factory-built thermal batteries that store low-cost electricity as heat in insulated solid-carbon blocks and deliver that energy as heat or power on demand. The company says its systems can store energy for multiple days, avoid supply-constrained critical minerals, and be deployed faster than conventional multi-year projects. Antora recently brought one of the largest battery storage projects online—a 5 gigawatt-hour system in South Dakota that moved from construction to energy delivery in under 12 months—and expanded its San Jose factory into a three-building manufacturing campus. The company reports a growing pipeline of signed agreements with hyperscalers and industrial customers and states its deployments have created and supported hundreds of U.S. manufacturing and construction jobs. With the $550 million Series C, Antora plans to expand production capacity, establish a second U.S. manufacturing hub, and strengthen its domestic supply chain. The company positions its technology as a tool to deliver affordable, reliable energy at scale to industry, data centers, and the grid.

Participated · Series B · Apr 2026

Sepion Technologies develops ultra-thin, drop-in polymer separator coatings and membrane technologies intended to replace legacy ceramic materials in lithium-ion batteries. Its coatings aim to enable higher energy density, faster charging, and improved durability without requiring changes to existing battery manufacturing lines. The company reports its products are currently being manufactured on commercial production lines to support customer qualification with leading global battery manufacturers. Sepion is supporting multiple concurrent qualification programs for electric vehicle, energy storage system, and consumer electronics applications. Led by CEO Peter Frischmann and based in Alameda, CA, the company plans to use recent funding to scale U.S.-based polymer production, expand product lines, and strengthen quality and operations.

Participated · Series E · Dec 2025

Fervo Energy develops next-generation geothermal power using innovations in horizontal drilling, fiber-optic sensing and advanced reservoir engineering to make geothermal scalable and competitive. Its flagship Cape Station project in Beaver County, Utah is slated to deliver first power to the grid in 2026, reach about 100 MW of operating capacity by early 2027 and has plans to scale to 500 MW. Cape Station is fully contracted through power purchase agreements with Southern California Edison, Shell Energy and community choice aggregators. The company secured long-term non-recourse project financing for the first phase of Cape Station to fund remaining construction costs and meet counterparty credit support requirements. Fervo positions its technology and commercial contracts as enabling Enhanced Geothermal Systems to be treated as a bankable, utility-scale infrastructure asset.

Participated · Seed · Jul 2025

Still Bright develops a vanadium-based electrochemical extraction system that soaks copper-containing ores in a regenerable vanadium solution to recover copper without the high-pollution pyrometallurgical steps. Inspired by vanadium flow batteries, the process electrically regenerates the spent solution and can recover nearly all copper from typical ores and from tailings. Its modular equipment is much smaller than traditional refiners because processing happens in minutes to an hour, enabling installations across a range of mine sizes. The company says its equipment costs 70–90% less than typical pyrometallurgical gear and currently runs at similar operating costs to a typical refinery, with expectations to become cheaper. Still Bright operates a pilot that produces about two tons of copper per year and plans a demonstration unit in 2027–2028 capable of producing 500 tons per year, targeting a commercial system of 10,000 tons annually. Founded in 2022 and based in New Jersey, Still Bright aims to scale to become one of the lowest-cost copper producers by enabling recovery from existing ores and waste streams.