# How Rondo Energy Stores Electricity as High-Temperature Industrial Heat > A system that converts cheap renewable electricity into continuous, high-temperature heat for factories by using two stages of thermal storage units that can charge and discharge independently. - **Patent:** US 12486789 - **Original title:** Thermal energy storage systems for use in material processing - **Owner:** Rondo Energy Inc - **Granted:** 2025 - **Status:** Active - **Times cited:** 0 - **Field:** energy, mechanical, industrial_manufacturing ## What it does This system uses a two-stage thermal battery design to turn electricity into steady industrial heat. A primary storage unit is heated by electricity, which then warms a working fluid. This fluid travels to secondary storage units, which act as heat exchangers to warm up a process gas for industrial use. By having multiple secondary units, the system can charge one unit while another is discharging, ensuring the factory receives a constant stream of heat even if the electricity source is intermittent. ## What it does NOT cover - Does not cover systems that lack a two-stage architecture with primary and secondary storage units. - Does not cover direct electrical heating of process gases without the intermediate working fluid stage. - Does not cover thermal storage systems that cannot operate in charging and discharging modes simultaneously. ## The clever bit The system uses a two-stage design where the working fluid and the process gas can be at different pressures and compositions, allowing the heat storage medium to be isolated from the industrial process gas itself. ## Real-world examples 1. Rondo Heat Battery 2. Industrial brick-based thermal energy storage 3. Renewable-powered cement manufacturing ## Why it matters Industrial processes like cement and steel production require massive amounts of constant heat, usually provided by burning fossil fuels. This patent provides a pathway to replace those fuels with renewable electricity by solving the 'intermittency problem'—the fact that wind and solar power aren't always available when a factory needs them. ## Frequently asked questions ### What does How Rondo Energy Stores Electricity as High-Temperature Industrial Heat cover? A system that converts cheap renewable electricity into continuous, high-temperature heat for factories by using two stages of thermal storage units that can charge and discharge independently. ### Who owns patent US 12486789? Rondo Energy Inc owns this patent, granted in 2025. ### When does this patent expire? This patent is expected to expire on December 2, 2045, when the invention enters the public domain. ### What problem does this patent solve? Industrial processes like cement and steel production require massive amounts of constant heat, usually provided by burning fossil fuels. This patent provides a pathway to replace those fuels with renewable electricity by solving the 'intermittency problem'—the fact that wind and solar power aren't always available when a factory needs them. ### What does this patent NOT cover? Does not cover systems that lack a two-stage architecture with primary and secondary storage units. **Full plain-English explainer:** https://patentbrief.org/patent/us/12486789/spacex-structures-philosophy **Original patent:** https://patents.google.com/patent/US12486789 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [Smart Energy System for Power, Heating, and Cooling Grids](https://patentbrief.org/patent/us/10480867/combined-heating-power-and-cooling-apparatus-with-energy-storage-type-adapted-to) — This patent describes a complex energy system that combines electricity generation, heating, and cooling with energy storage to help power grids manage their load more flexibly. - [Capturing Carbon Dioxide While Making Industrial Materials](https://patentbrief.org/patent/us/20220203297/systems-and-methods-for-carbon-capture) — This patent describes a system and method for capturing carbon dioxide released during industrial processes like making cement or steel, while also producing useful materials and recovering energy. - [How a Special Reactor Makes Methane Fuel Without Constant Electricity](https://patentbrief.org/patent/us/10145018/method-for-operating-an-soec-type-stack-reactor-for-producing-methane-in-the-abs) — This patent describes a method for a Solid Oxide Electrolyser Cell (SOEC) reactor to produce methane, even when electricity is scarce, by switching from electrolysis to a heat-generating chemical reaction. - [How Heated Water and Compressed Air Generate Electricity](https://patentbrief.org/patent/us/11532949/system-for-energy-storage-and-electrical-power-generation) — This patent describes a system that stores energy as compressed air and generates electricity by injecting that air into heated water, creating an upward flow that drives a hydro-electric turbine. - [How a High-Temperature Fuel Cell System Starts, Stops, and Recycles Fuel](https://patentbrief.org/patent/us/7846599/method-for-high-temperature-fuel-cell-system-start-up-and-shutdown) — This patent describes a fuel cell system that uses a smaller, secondary fuel cell to power itself during startup and shutdown, and to recycle hydrogen from its exhaust during normal operation.