Episode Summary
Executive Summary: John O’Donnell explains how Rondo Energy uses low-cost renewable electricity to make and store industrial heat at extreme temperatures in brick-based thermal batteries. The conversation covers why industrial heat is hard to decarbonize, comparisons with hydrogen, batteries, natural gas, and carbon capture, and how new financing models are enabling deployment across chemicals, food, paper, cement, and steel.
Main Topics: Why industrial heat is a major climate problem (Priority: 5/5): Industrial heat underpins production of chemicals, steel, cement, paper, food, and fuels, and is still overwhelmingly powered by coal, oil, and natural gas. O’Donnell frames it as one of the largest untapped decarbonization opportunities. Why renewables finally change the economics (Priority: 5/5): Solar and wind have become cheap enough that electricity can now beat fossil fuel on an input-cost basis in many places, creating a new economic case for electrifying heat, not just a climate case. Rondo’s brick-based heat battery technology (Priority: 5/5): Rondo converts electricity to heat with resistive elements and stores it in a highly insulated brick core, enabling high-temperature heat delivery with very high efficiency and long-duration storage. Competitive landscape: hydrogen, batteries, natural gas, and carbon capture (Priority: 4/5): The discussion compares Rondo’s approach with hydrogen combustion, grid batteries, continued fossil fuel use, and carbon capture, arguing that thermal storage is cheaper and more efficient for many industrial heat applications. Industrial deployment and use cases (Priority: 4/5): Rondo is targeting heat-as-a-service for industrial customers, starting with steam and progressing toward higher-temperature applications such as cement calcination and steel-related processes. Project finance and commercialization (Priority: 4/5): A major theme is how project finance is adapting to first-of-a-kind climate infrastructure, with lenders and developers increasingly financing end-to-end systems that include generation, storage, and industrial load. Grid and market value of flexible thermal loads (Priority: 3/5): Rondo’s systems can absorb curtailed or negative-priced electricity, act as dispatchable loads, and in some cases support combined heat and power, creating value for both factories and grids.
Key Arguments: Industrial heat is a quarter of global CO2 emissions and a quarter of final energy use, yet it remains almost entirely fossil-fueled. Renewable electricity has become cheaper than fossil energy in many places, making electrified heat economically viable for the first time at scale. Electricity can be converted to heat at 100% efficiency; the main challenge is storing it cheaply and safely at industrial temperatures. Rondo’s thermal storage is 98% efficient and materially cheaper than lithium-ion storage for heat applications because bricks are low-cost, abundant, and durable. Hydrogen can solve industrial heat, but it is roughly half as efficient as direct electric thermal storage and adds electrolysis, compression, and combustion losses. Carbon capture increases costs and fuel use, and at scale would require an infrastructure buildout comparable to the global petroleum industry. Industrial customers care about continuous, reliable, on-site heat, so solutions must function inside the factory fence and fit existing processes. Heat-as-a-service can be a drop-in replacement that changes only the fuel source, not the factory itself, which lowers adoption friction. Project finance is becoming more sophisticated about financing integrated energy systems rather than isolated generation assets. Flexible industrial thermal loads can help grids by soaking up excess renewable power and reducing curtailment or negative pricing events.
Data Points: Industrial heat share of global CO2: 25% - O’Donnell says industrial heat alone is a quarter of world emissions. Industrial heat share of final energy use: 25% - He states industrial heat is also a quarter of global final energy use. Global industrial heat replacement need: ~10,000 GW - He cites an IEA-based estimate of the power needed to repower industrial heat using clean energy. Rondo / GlassPoint scale built historically: 0.3 GW - He notes they built more than half of all solar industrial heat running worldwide, totaling about 0.3 GW. World solar/wind needed vs existing: About 5x more than currently exists - He says industrial heat would require roughly five times the world’s installed wind and solar capacity. Maximum storage temperature: Up to 1500°C - Rondo’s brick system can store heat at very high temperatures for industrial processes. Thermal battery efficiency: 98% - O’Donnell says Rondo’s system is 98% efficient, near the top of electric thermal storage systems. Best electric thermal storage efficiency range: 90%+ - He says the least efficient systems in the category are around 90% efficient. Hydrogen pathway efficiency: ~50% - He characterizes the hydrogen route to continuous heat as about 50% efficient best case. Lithium-ion efficiency: 90–92% - He compares Rondo’s thermal storage favorably to lithium-ion battery efficiency. Oklahoma negative price hours: 2,000 hours - Used as an example of renewables oversupply and the value of flexible load. Calgary Renewable Fuels pilot: World’s highest-efficiency energy storage at highest temperature - Describes Rondo’s operating pilot at a California biofuel refinery. Industrial heat project size: 180 MW to a couple thousand MW - He says a single industrial site can have very large thermal demand. Rondo larger unit size: 10 by 30 meters - Size of the larger product with 320 MWh storage. Rondo larger unit storage: 320 MWh - Energy capacity of the larger unit. Rondo smaller unit size: 30 by 30 feet - Size of the smaller product. Rondo smaller unit storage: 120 MWh - Energy capacity of the smaller unit. Heat battery lifespan: 40 years - He says the systems last for decades with no deterioration. Cement calcination emissions: 2%–3% of world emissions - He estimates calcination heat alone is a major emissions source. Steel/cement-related temperature capability: 1100°C to 1500°C - Ceramic heaters enable higher temperatures than metal heaters. Daily cycling: Fully charged and discharged every day - He describes the operating pattern of the thermal battery. Tesla comparison: 8,571 Teslas - He says one larger Rondo unit can save as much CO2 per year as 8,571 Teslas.
Pivotal Quotes: "This is the definition of green premium." — John O'Donnell: He explains why carbon capture adds cost without creating corresponding downstream value. "The zero carbon future can be cheaper than business as usual." — John O'Donnell: He describes the moment when renewable electricity and thermal storage become economically competitive. "The more you know about it, the less you like it." — John O'Donnell: His view on molten salt storage from prior work, highlighting why Rondo chose a different approach.
Implications: Industrial heat is becoming a major clean-energy market, not just a hard-to-abate climate problem. If thermal storage scales, factories can buy cheaper renewable heat, grids gain flexibility, and decarbonization can proceed faster without major process redesign.