Participated · Equity · Apr 2026

Vateris operates a proprietary carbon mineralization process that converts industrial flue gas CO2 into GypCarb, a mineral additive for cement and concrete, while co-producing a mineral fertilizer. Its GypCarb product is positioned as a drop-in additive designed to deliver performance and economic benefits without requiring changes to existing production infrastructure. The company has commissioned a pilot plant and is scaling toward a first commercial plant that would be co-located with a partner to take flue gas directly. Vateris recently rebranded from Concrete4Change to reflect its transition from a concept to a precision carbon-to-materials platform focused on engineering vaterite. To support commercialization and industrial execution it has expanded its commercial team with senior hires from the building materials and fertilizer sectors. The company has secured strategic investment from industry players to validate potential integration into mainstream cement production and European construction chemicals channels.

Participated · Series A · Dec 2024

Electrified Thermal Solutions develops the Joule Hive Thermal Battery (JHTB), an MIT-developed system that uses electrically and thermally conductive patented bricks to generate, store, and deliver near-flame temperatures up to 1,800°C. The JHTB is positioned to electrify industrial heat by leveraging renewable electricity to replace fossil-fuel combustion in boilers, dryers, and furnaces. The company emphasizes integration with existing infrastructure and targets sectors including cement, mining, metals, chemicals, power, and food processing. Electrified Thermal says industrial heat processes account for over 20% of global greenhouse gas emissions, making its zero‑carbon heat approach relevant to hard‑to‑abate industries. The company plans a commercial demonstration in 2025, aims to commercialize the JHTB by 2026, and targets deploying 2 GW of thermal power capacity by 2030. It raised $19 million in venture financing to accelerate its commercial demonstration, scale manufacturing, and expand its industrial customer base. Electrified Thermal Solutions builds the Joule Hive — a thermal battery made from electrically conductive 'e-bricks' doped with semiconductor materials. The bricks are heated by running electricity through them like a toaster, can store heat for hours or days, and ETS says over 95% of input electricity can be recovered as heat. A stack can reach temperatures nearing 2,000°C, enabling use in steel, glass, cement and chemical plants, as well as steam generation or power turbines. ETS says its heat is at least three times cheaper than hydrogen and can be competitive with natural gas in regions with low electricity prices or when a $50/metric-ton carbon price is applied. The company has worked with a brick maker to adapt recipes for industrial-scale equipment, is operating a pilot system about the size of an elevator, and is designing a shipping-container-scale commercial unit. ETS plans to sell either heat from the batteries or the complete system; the technology stems from about a decade of work beginning with CEO Dan Stack's graduate research at MIT. Financially, ETS has raised $4.75 million to date, including a $4.5 million seed round led by Clean Energy Ventures.

Led · Equity · Jun 2024

Travertine commercializes the Travertine Process, which combines salt-splitting electrolysis, caustic direct air capture, and mineralization to convert waste gypsum and atmospheric CO2 into sulfuric acid, green hydrogen, and calcium carbonate (permanent carbon storage). The company is building a demonstration plant at Sabin Metal's main facility outside Rochester/Scottsville, New York, with engineering underway and commissioning expected in mid-2025. The demo is sized to upcycle hundreds of tons per year of gypsum, remove tens of tons of CO2 annually, and supply roughly 50% of Sabin Metal’s annual sulfuric acid needs; future expansion could supply green hydrogen for industrial heat. Travertine says the process can decouple critical element extraction and refining from fossil-derived sulfur and is applicable to lithium, nickel, phosphorus, and cement production. The company is headquartered in Boulder, Colorado and is led by founder and CEO Laura Lammers, PhD. Travertine’s core technology upcycles industrial sulfate waste and CO2 captured directly from the air into sulfuric acid and carbonate advanced cement components that permanently sequester CO2. The produced sulfuric acid is used to extract phosphorus, lithium, nickel, and other critical elements from ores, while eliminating sulfate wastes from conventional extractive processes. The company has demonstrated its process by upcycling sulfate waste from major fertilizer and mining companies in a fully integrated, continuous-flow pilot. Travertine is currently focused on engineering and scale-up for a first commercial demonstration plant. The company plans to use recent funding to expand operations and further its development efforts. Travertine spun out of Laura Lammers’ lab at the University of California, Berkeley in 2022 and is based in Boulder, Colorado. Travertine Technologies develops a novel, cost-effective process to capture and permanently sequester ambient CO2 while producing sulfuric acid. The company aims to enable carbon-negative critical element extraction and fertilizer production through its co-produced sulfuric acid. It is building a pathway to pilot-scale implementation in 2023. The $3M seed investment will be used to scale up the team in Boulder, CO and accelerate that pilot pathway. Travertine was founded by Prof. Laura Lammers and describes its ambition as a gigaton-scale carbon dioxide removal solution. The firm combines CDR with industrial chemical production to address both emissions and raw-material needs.