Malta Inc

Malta Inc. is a Cambridge, MA-based clean energy company that develops ultra-high temperature thermal energy systems-most notably its Steam Energy Management and Storage (SEMS) platform and Advanced Heat Pump (AHP). Originally incubated at X (Alphabet's Moonshot Factory) based on the theoretical work of a Nobel Prize-winning Stanford physicist, Malta spun out as an independent company in 2018. Its core innovation is a pumped-heat energy storage system that uses steam as a working fluid and stores thermal energy in molten salt, which can be reconverted into electricity and process heat on demand. The AHP delivers 300-550°C process heat with industry-leading efficiency (coefficient of performance of ~4.6), making it capable of supporting long-duration energy storage from 8 hours to multiple days at grid scale.

Malta's technology addresses two critical gaps in the energy transition: the need for affordable, long-duration energy storage and the electrification of industrial heat. Its systems can be retrofitted onto existing fossil fuel infrastructure-such as combined cycle gas turbines, methanol plants, and refineries-enabling decarbonization without wholesale replacement of capital assets. The first commercial deployment is currently underway at Proman's methanol plant in Pampa, Texas, where an 11 MWth AHP system will recover waste heat and reduce boiler gas consumption by 61% while cutting CO₂ emissions significantly. Malta's use cases span utilities, data centers, geothermal plants, district heating/cooling, and heavy industry sectors like steel, chemicals, and aluminum.

For the US energy supply chain, Malta represents a compelling and differentiated thermal storage solution that can accelerate grid flexibility, industrial decarbonization, and coal plant repowering-all using domestically manufacturable, off-the-shelf components with established supply chains. Its technology is gaining global recognition, having been named to TIME Magazine's World's and America's Top GreenTech Companies lists in both 2024 and 2025, and recognized as the Most Promising Climate Tech Startup in North America in 2023. With partnerships forming with global energy majors like ACWA and BBVA, and its first US commercial deployment live, Malta is well-positioned to play a meaningful role in America's clean energy infrastructure buildout.