Thermal energy storage in 2026: overview
Thermal energy storage captures heat or cold for later use, helping match energy supply with demand. Systems can store heat as a temperature change in a material, through a phase change, or in reversible chemical reactions. This makes storage relevant to renewable integration and industrial electrification: heat can be supplied when needed even if electricity or solar heat was available earlier. The central engineering challenge is delivering stored energy at the right temperature and rate, with manageable losses and cost.
Recent work is tackling material limits and system design together. In September 2026, studies examined metal-foam and nanoparticle enhancements for phase-change materials, separator plates to improve melting, and graphite-containing concrete pebbles for sensible heat storage. Other research tested hybrid packed beds that combine phase-change materials with quartzite to widen the operating range. On the deployment side, Rondo Energy and Covestro broke ground on a 100 MWh industrial heat-storage system in Germany in January 2026, illustrating the push from laboratory materials toward continuous process heat.
- 1From electricity to process heat: Industrial process heat activity grew 20% in the latest comparison, while Rondo Energy and Covestro’s January 2026 project signals commercial interest in solid-block heat batteries.
- 2Materials meet heat transfer: Phase-change materials offer compact latent-heat storage, but low thermal conductivity and leakage remain barriers, driving work on metal foams, nanoparticles and shape-stable composites.
- 3New routes gain attention: Thermochemical storage activity grew 18.3% in the latest comparison, although reactor design and durable materials still need to prove their value in deployed systems.
Top organizations working on thermal energy storage
Ranked by Linknovate activity score · last 24 monthsThe activity score adds up the relevance of every patent, publication, grant and news item linking an organization to thermal energy storage. Showing 7 of 2,456 organizations.
| # | Organization | Approach | Signals (24 mo) | Momentum | Why it matters |
|---|---|---|---|---|---|
| 1 | 
Xi'an Jiaotong University
Research · China |
Thermochemical storage | PUB 218 · NEWS 1 | -1% | Recently, researchers investigated a rotating moving-bed reactor for thermochemical storage, alongside designs to improve melting in latent-heat units. The university also studies hybrid phase-change and thermochemical materials for high-temperature heat storage. |
| 2 | Latent heat materials | PAT 1 · PUB 200 NEWS 6 |
+35% | Recently, researchers studied helical-tube and triple-tube phase-change storage units, examining their heat storage and release performance. Other work explores nitrate-based composite phase-change materials and molten-salt storage for combined heat and power. | |
| 3 | 
University of Birmingham
Research · United Kingdom |
Thermochemical storage | PUB 98 · NEWS 17 | +35% | Recently, researchers investigated salt-hydrate thermochemical storage designs and falling-particle reactors for direct solar heat storage. They also study high-temperature packed-bed materials and latent-heat storage for heat applications. |
| 4 | 
Rondo Energy Inc.
Startup · United States |
Solid sensible heat | PAT 39 · NEWS 41 | -5% | Its heat battery electrically heats solid storage blocks to supply continuous, high-temperature industrial heat. Patents address system insulation, seismic stability and heater control. |
| 5 | 
Brenmiller Energy
Corporate · Israel |
Solid sensible heat | NEWS 102 | -81% | Brenmiller develops thermal storage systems for supplying heat to industrial users and is positioning its bGen system for integration with small modular reactors. Its work focuses on storing heat in solid media for later delivery. |
| 6 | 
Beijing University of Technology
Research · China |
Liquid sensible heat | PUB 93 | +32% | Recently, researchers investigated vanadium-tailings phase-change composites for packed-bed storage and molten-salt latent storage. The university also studies nitrate and nitrite molten salts for high-temperature thermal systems. |
| 7 | 1U
12579Southeast University
Research |
Latent heat materials | PUB 97 · NEWS 1 | +8% | Recently, researchers developed hierarchical metal-foam structures for latent-heat storage and used machine learning to optimize solar-driven calcium looping. The university also studies phase-change storage and thermochemical materials. |
| 8 | ··Hidden organizationCompany | Approach | PAT 00 · PUB 00 GRANTS 0 · NEWS 00 | +00% | Available to registered users. |
| 9 | ··Hidden organizationCompany | Approach | PAT 00 · PUB 00 GRANTS 0 · NEWS 00 | +00% | Available to registered users. |
| 10 | ··Hidden organizationCompany | Approach | PAT 00 · PUB 00 GRANTS 0 · NEWS 00 | +00% | Available to registered users. |
Startups to watch and leading research centers
Startups to watch 33 total
- Rondo Energy Inc.United StatesIts heat battery electrically heats solid storage blocks to supply continuous, high-temperature industrial heat. Patents address system insulation, seismic stability and heater control.
Kyoto Group ASKyoto Group develops molten-salt thermal batteries for industrial heat. Its projects include a reported 56 MWh storage system for a Hungarian corn-processing plant.
Electrified Thermal SolutionsRecently, Electrified Thermal Solutions announced a 20 MWh Joule Hive deployment as part of Holcim’s industrial electrification roadmap. The system stores electricity as high-temperature heat in conductive solid materials.- ··Hidden startupCountryAvailable to registered users, with funding and founding year.
- ··Hidden startupCountryAvailable to registered users, with funding and founding year.
Leading research institutions 2,012 total
- Xi'an Jiaotong UniversityChinaRecently, researchers investigated a rotating moving-bed reactor for thermochemical storage, alongside designs to improve melting in latent-heat units. The university also studies hybrid phase-change and thermochemical materials for high-temperature heat storage.
North China Electric Power UniversityRecently, researchers studied helical-tube and triple-tube phase-change storage units, examining their heat storage and release performance. Other work explores nitrate-based composite phase-change materials and molten-salt storage for combined heat and power.- University of BirminghamUnited KingdomRecently, researchers investigated salt-hydrate thermochemical storage designs and falling-particle reactors for direct solar heat storage. They also study high-temperature packed-bed materials and latent-heat storage for heat applications.
- ··Hidden research institutionCountryAvailable to registered users, with their key researchers.
- ··Hidden research institutionCountryAvailable to registered users, with their key researchers.
Where thermal energy storage innovation happens
Share of documents with at least one organization from each country.
Open the interactive map with all 2,456 organizationsMain technical approaches
Last 24 months| Approach | What it is | Documents | Leading organizations |
|---|---|---|---|
| Liquid sensible heat | Stores heat by raising a liquid’s temperature; it is established and practical, but capacity depends on temperature range and tank size. | 1,483 |
North China Electric Power University, Brenmiller Energy, Beijing University of Technology |
| Solid sensible heat | Stores heat as solid materials warm and cool; it can serve high-temperature loads, but heat transfer and discharge control can limit performance. | 327 |
North China Electric Power University, Pontificia Universidad Catolica de Chile, KTH Royal Institute of Technology |
| Latent heat materials | Stores or releases heat during a material’s phase change; it can pack substantial storage into a compact system, but conductivity, leakage and cycling stability are challenges. | 4,574 |
Xi'an Jiaotong University, United Arab Emirates University, King Khalid University |
| Thermochemical storage | Stores heat in reversible chemical reactions; it can support long-duration storage, but reactor complexity and material durability constrain deployment. | 155 |
Calmac, CSP GmbH & Co. KG, Siemens AG |
| Carnot batteries | Convert electricity into heat for storage and later reconvert it to electricity; they offer long-duration flexibility, but conversion losses affect economics. | 1,041 |
Brenmiller Energy, EGen LLC, LinkedIn |
Emerging trends
Last 12 months vs previous 36 monthsTerms whose frequency in the last 12 months grew the most compared with the previous 36 months.
Funding and investment
Recent funding rounds
FACTS records $341,153,497 in grant funding across 200 grants since 2020. NEWS reports that MGA Thermal raised US$12 million in March 2026 and received US$2.31 million from ARENA in February 2026 for front-end engineering design studies.
Patent landscape
Top patent holders · last 24 monthsRecent developments
Latest news, duplicates removed- Sep 2026The Ministry of New and Renewable Energy (MNRE) has invited proposals for concentrating solar thermal (CST) technology for Indian industries under the Renewable Energy Research and Technology Development (RE-RTD)…Renewable Watch
- Aug 2026News provided byHanbat National University Aug 17, 2026, 08:32 ET The proposed physics-informed neural network framework enables rapid, autonomous design optimization of latent heat thermal energy storage systems…All Environment
- Jul 2026Thermal Energy Storage: The $102.6 Billion Unsung Hero of the Energy Transition Everyone loves to talk about lithium-ion batteries. We see them in our iPhones. We see them in our Teslas. Consequently, they get all the…Green Living Guy
- Jul 2026The face of energy security is changing. Historically, fossil fuels have represented security thanks to their established supply chains and round-the-clock production potential, while renewable energies represented risk…Oil price
- Month 20XXHidden developmentAvailable to registered users with alerts enabled.
Frequently asked questions about thermal energy storage
What companies are working on thermal energy storage?
Rondo Energy Inc., Brenmiller Energy and Kyoto Group AS are among the companies developing thermal energy storage. Rondo uses electrically heated solid blocks for industrial heat, while Brenmiller develops solid-media systems and Kyoto Group works with molten-salt thermal batteries. Other active players include Electrified Thermal Solutions, which announced a Joule Hive deployment with Holcim, and Nostromo Energy, which develops cold storage.
Which thermal energy storage startups are notable in 2026?
Rondo Energy Inc., Kyoto Group AS and Electrified Thermal Solutions are notable startups in the available data. Rondo’s projects target industrial heat, including a system with Covestro in Germany. Kyoto Group develops molten-salt storage, while Electrified Thermal Solutions stores electricity as high-temperature heat in conductive solids. MGA Thermal is also scaling its technology and reported funding for engineering studies in 2026.
Which universities and research centers lead thermal energy storage research?
Xi'an Jiaotong University, North China Electric Power University and the University of Birmingham are leading research contributors in the available data. Their work spans thermochemical reactors, phase-change units, salt-hydrate systems and high-temperature storage. The National Renewable Energy Laboratory also contributes research on building and grid applications, including techno-economic assessment and the Stor4Build consortium.
How much funding has thermal energy storage received?
FACTS records $341,153,497 in grant funding across 200 grants since 2020. NEWS also reports recent company funding: MGA Thermal raised US$12 million in March 2026 and received US$2.31 million from the Australian Renewable Energy Agency in February 2026 for engineering design studies. These figures represent reported grants and selected company funding, not a single complete estimate of all investment.
Who holds the most thermal energy storage patents?
Rondo Energy Inc. is the leading patent holder in FACTS, with 39 patents. Carrier Corporation Company follows with 17, while MItsubishi Electric and Holtec International each have 12. Other listed holders include Denso Corporation, Robert Bosch GmbH and Octopus Energy Ltd. The counts identify patent activity in the supplied holder data, rather than the full size of each company’s patent portfolio.
Is thermal energy storage patent activity growing?
No: patent activity declined 15% in the latest 12-month comparison, with 590 patents recorded in the 24-month window. Publication activity moved in the opposite direction, with 4,043 publications in the last year and growth of 3.9%. This contrast suggests that research output remains active even as recent patenting has softened.
What are the main approaches in thermal energy storage?
The main approaches include liquid sensible heat, solid sensible heat, latent heat materials, thermochemical storage and Carnot batteries. Sensible systems store heat through a temperature change; latent systems use a phase change; thermochemical systems use reversible reactions. Carnot batteries convert electricity into heat for storage and later power generation. The best fit depends on the required temperature, duration, output and system economics.
Which countries lead thermal energy storage?
China leads the country data with 11,699 documents, followed by the United States with 8,668 and India with 3,849. The United Kingdom, Germany and Spain are also prominent. These figures reflect document activity, not a direct measure of installed storage capacity or commercial market share.
What are the applications of thermal energy storage?
FACTS identifies data centers, buildings and district heating, cooling and air conditioning, solar thermal power, and industrial process heat as applications. Data centers have the largest listed application activity, with 3,668 documents. Storage can shift heating or cooling loads, support renewable heat, and help supply industrial processes when energy is available at a different time.
What are the latest developments in thermal energy storage?
Recent developments include September 2026 research on phase-change materials, separator-plate designs and graphite-containing concrete pebbles. In January 2026, Rondo Energy and Covestro broke ground on a 100 MWh industrial storage system in Germany. Research is also exploring hybrid packed beds that combine phase-change materials and quartzite, while new designs continue to address heat transfer, leakage and system performance.