Participated · Equity · Aug 2023

Rondo Energy manufactures Rondo Heat Batteries (RHBs) that store intermittent wind and solar electricity as continuous, high-temperature heat and power for industrial processes. Its systems are designed for seamless integration with existing equipment to deliver high-pressure steam and power as a service, enabling “drop-in decarbonization” for industries that currently rely on fossil fuels. Rondo operates the world’s highest-temperature, highest-efficiency commercial energy storage system at Calgren Renewable Fuels in Pixley, California, and is expanding production capacity of its storage media with partner Siam Cement Group from 2 GWh/yr to 90 GWh/yr. The company is pursuing storage-as-a-service contracts and a large pipeline of global projects to replace industrial gas use with renewables. Recent project funding will support European deployments to deliver long-term low-cost clean energy under contracts with manufacturers and industrial parks. Rondo is headquartered in Alameda, California. Rondo Energy develops a heat battery that captures low‑cost renewable electricity and delivers high‑temperature, high‑efficiency energy storage to enable customers to power industrial operations with zero‑carbon energy. The company is led by CEO John O’Donnell and is headquartered in Alameda, California. In 2023 Rondo began operations of its first commercial unit, which lowered the carbon intensity of biofuel produced by Calgren Renewable Fuels. In partnership with Siam Cement Group (SCG) the company reported current Heat Battery production capacity of 2.4 GWh/year and plans to scale to 90 GWh/year. Financially, Rondo recently raised $60M and intends to use the funds to grow international operations and to develop and build storage projects around the world. Rondo Energy’s core product is the Rondo Heat Battery (RHB), which stores low-cost renewable electricity as high-temperature heat in brick and delivers dispatchable heat on demand at temperatures up to 1500°C. The technology is designed to decarbonize energy-intensive industrial processes and to eliminate Scope 1 and Scope 2 emissions while reducing operating costs for large energy users. Rondo says its approach leverages proven steel-industry experience with large-scale brick heat storage and the falling costs of wind and solar to offer low-cost zero-carbon heat. The company plans to scale manufacturing capacity, originate customer projects, and develop services for heavy industry and energy producers, including Heat as a Service offerings. Rondo and its investors intend to deploy the technology at scale across sectors such as cement, chemicals, paper, and packaging. Recent funding—from Siam Cement Group alongside existing backers—will support earlier deployments and enable rapid production and wider commercial rollouts across Southeast Asia and worldwide. Rondo Energy develops a high-temperature thermal storage system—the Rondo Heat Battery—that stores renewable electricity as heat in engineered solid materials. Its system uses resistive heating to heat engineered "brick" materials and AI-powered controls to supervise charging and discharge, delivering superheated air that can be converted to steam or supplied directly to high-temperature industrial processes. Rondo says its storage operates at up to 1,200°C and claims roughly 98% round-trip efficiency, positioning the technology as cheaper and simpler than electrochemical batteries or hydrogen systems. Target customers include food processing, oil production, cement manufacturing, hydrogen generation and raw-material refining—sectors that consume large amounts of industrial heat. The company raised $22 million in a Series A to begin manufacturing and delivering customer systems later this year. Rondo frames its technology as a way to use excess midday renewable power to decarbonize industrial heat and highlights California as its home state and an important market for industrial gas consumption.