Caldera
Caldera Heat Batteries Limited designs and manufactures electric Storage Boilers using proprietary Heat Cell technology — vacuum-insulated thermal storage with an aluminium-rock composite — to deliver industrial steam and hot water from renewable electricity, serving brewers, distillers, food processors, pharma manufacturers, and NHS hospitals.
- Company typePrivate
- Founded2017
- HeadquartersFareham, United Kingdom
- Headcount11–50
- GTM typeB2B
- OfferingHardware or Manufacturing
What Caldera does
Caldera Heat Batteries Limited is a UK-based industrial decarbonization company founded in 2017 by James Macnaghten and Guy Winstanley. It designs and manufactures electric Storage Boilers that combine an electric boiler with integrated thermal storage, converting renewable electricity into stored heat for on-demand delivery as industrial steam or hot water. The core technology is the patented Heat Cell — a vacuum-insulated chamber filled with a proprietary composite of recycled aluminium and volcanic basalt rock — which can store heat at up to 500°C and deliver steam at temperatures between 80–210°C. Modular Heat Cells (1.3–5.3 MWh each) are combined into systems ranging from 5 to 100+ MWh, complemented by a Power & Control Module (variable 0–100% charging) and an Ultra-Pure Water Treatment Package.
The company's primary revenue stream is direct hardware sales of these configurable, turnkey Storage Boiler systems to industrial customers, supplemented by site assessment, engineering, and project services. Sales cycle is enterprise field-led, targeting brewing and distilling, food processing, pharmaceuticals, healthcare/NHS, paper, and industrial heat network operators. A secondary OEM channel supplies solar developers with embedded storage boilers, and a flagship Channel/Reseller partnership with GEA Group (combined with the March 2025 £10m Series A investment) provides global distribution into food, beverage, and pharmaceutical end-markets, especially when paired with GEA heat pumps. Pricing is bespoke per installation; independent analysis by Gemserv suggests fuel-bill savings of up to 45% and payback under six years for typical industrial deployments.
Since founding, Caldera has progressed from a 100 kWh domestic prototype (2019–2020) to a 4 MWh industrial demonstrator (2024) and its first commercial 10 MWh NHS hospital order (March 2025). Capital sources include two Crowdcube equity crowdfunding rounds (£1.5m each in 2021 and 2024), £5.1m in cumulative UK Government grants (Department for Energy Security & Net Zero, 2022 and 2023), and the £10m GEA Series A. The company employs approximately 30 people across engineering, commercial, and operations roles, headquartered in Fareham, Hampshire.
Caldera firmographics
Firmographics- Name
- Caldera
- Legal name
- Caldera Heat Batteries Limited
- Website
- https://caldera.co.uk
- Company type
- Private
- Founded year
- 2017
- Operating status
- Operating
- Headcount range
- 11–50 employees
- Short description
- Caldera Heat Batteries Limited designs and manufactures electric Storage Boilers using proprietary Heat Cell technology — vacuum-insulated thermal storage with an aluminium-rock composite — to deliver industrial steam and hot water from renewable electricity, serving brewers, distillers, food processors, pharma manufacturers, and NHS hospitals.
- Ownership category
- akta.pro rank
Caldera industry classification
Industry- Product category
- Industrial Thermal Energy Storage Equipment
- NAICS
- Power Boiler and Heat Exchanger Manufacturing (33241), Heating Equipment (except Warm Air Furnaces) Manufacturing (333414)
- SIC
- Heating Equipment, Except Electric & Warm Air Furnaces (3433), Fabricated Plate Work (Boiler Shops) (3443)
- akta.pro primary industry
- Boilers, Furnaces & Process Heating Equipment (IMAHAKAD)
- akta.pro secondary industries
- Thermal LDES (High-Temperature, Molten Salt, Carnot/Heat-to-Power) (EUAFADAC), Industrial Boilers, HRSGs & Steam Generators (IMAHAFAF), Heat Transfer Equipment (Heat Exchangers, Boilers, Condensers) (IMAHAEAC)
Keywords
Where Caldera is headquartered
LocationHeadquarters
- HQ city
- Fareham
- HQ country
- United Kingdom
- HQ region
- Europe
Offices1 record
Markets served
Caldera business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Technology or R&D, Supply Chain, Personnel, Operations, Marketing or Sales, Infrastructure
Revenue model
- Electric Storage Boiler Sales: Sale of industrial-scale electric storage boiler systems including Heat Cells, Power & Control Module, and Ultra-Pure Water Treatment Package. Systems are modular and configurable, sold as complete turnkey solutions with capacities ranging from 5 MWh to 100+ MWh.
- Solar Developer OEM Supply: Supply of storage boilers as OEM components for solar developers to integrate into their project offerings, enabling expanded project scope and differentiation.
- Engineering & Project Services: Site suitability assessments, system specification, and project execution support services provided alongside hardware sales for enterprise customers.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Other | Multi-year contract | Custom industrial storage boiler systems priced based on storage capacity, power output, and site requirements |
Go-to-market motion4 records
Distribution channels4 records
Marketing channels6 records
Caldera product offering
Product offeringCore offering
Caldera designs, manufactures, and sells industrial-scale electric Storage Boilers that combine an electric/electrode boiler with integrated thermal storage using proprietary Heat Cells (recycled aluminium and volcanic rock composite in vacuum-insulated chambers). The systems convert renewable or grid electricity into stored heat and deliver process steam up to 16 bar (~204°C) or hot water on demand for industrial customers in brewing, distilling, food processing, pharmaceuticals, paper, and healthcare. Configurable modular storage capacity from 5 MWh to 100+ MWh, sold as turnkey installations alongside site assessment, system design, and project execution services.
Product overview
Caldera offers a unified electric Storage Boiler system for industrial decarbonization, combining Heat Cells containing a proprietary aluminium-rock composite with supporting modules. The core Storage Boiler integrates modular Heat Cells (1.3-5.3 MWh each), the Power & Control Module for variable charging, and an Ultra-Pure Water Treatment Package. Systems are configurable from 5 to 100 MWh storage capacity and deliver steam up to 16 bar (204°C), targeting industries including pharmaceuticals, food processing, brewing, distilling, and paper manufacturing.
Differentiator
Problem solved
Functional benefit
Products and services
- Electric Storage Boiler Modular industrial-scale electric boiler with integrated thermal storage that converts renewable or grid electricity into reliable process steam (up to 16 bar / ~204°C) or hot water on demand. Configurable storage capacity from 5 MWh to over 100 MWh, designed as a turnkey 'plug and play' system that connects to existing steam distribution networks for industrial manufacturers in food, beverage, pharmaceutical, brewing, distilling, paper, and healthcare sectors.
- Power & Control Module Factory-assembled subsystem for the Storage Boiler containing switches and thyristor controls that enable variable charging from 0-100%. Delivers 2 MW at 690 V or 650 kW at 400 V, with an integrated energy management system for dynamic response to charging signals and heat demand.
- Ultra-Pure Water Treatment Package Water treatment subsystem that takes Reverse Osmosis water or condensate and runs further processes including a second stage of RO, CO2 removal, Electrodeionization (EDI), and de-oxygenation to produce ultra-pure water for the Storage Boiler's steam generation circuit. Can be co-located with the Storage Boiler or placed near existing water treatment equipment.
- Engineering and Project Services Site suitability assessments, system specification, and project execution support services delivered alongside Storage Boiler hardware sales to enterprise customers, ensuring installations are tailored to each industrial site's heat demand, available space, and integration requirements.
Quantifiable outcome
- Fuel bill savings of up to 45% compared to gas boilers
- +4 more outcomes
Companies that use Caldera
Customer profileNamed customers3 records
Segments7 records
Ideal customer profiles3 records
Caldera technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature5 records
Caldera partnerships and signals
Strategic signalPartnerships
Three partnerships are on record, tiered core.
- Tomatin DistillerycoreTomatin Distillery plans to partner with Caldera to decarbonize whisky production using wind-generated electricity stored as heat via Caldera storage boilers. Part of broader project with Fred. Olsen Renewables for dedicated wind farm power.
- Fred. Olsen RenewablescoreFred. Olsen Renewables is developing Balnespick Wind Farm (64.8MW) to provide dedicated electricity via private wire to Tomatin Distillery. Partnership enables integration of wind power with Caldera storage boilers for renewable heat generation.
- Manufacturing Technology Centre (MTC)coreCaldera partnered with MTC to design a heat cell gigafactory for mass manufacturing of low-carbon heat storage systems at scale. MTC brings expertise in advanced manufacturing techniques to support Caldera's production scaling ambitions.
Scale indicators13 records
Recent moves6 records
Expansion highlights6 records
Caldera competitors and assessment
Company assessmentDirect peers
- Malta Inc. US-based pumped heat thermal storage developer targeting grid-scale and industrial long-duration energy storage. Competes in the broader electrified thermal energy storage category.
- Brenmiller Energy: Israel-based provider of the bGen thermal energy storage system for industrial steam and heat decarbonization. Directly competes with Caldera's electric Storage Boiler in industrial markets.
- Kraftblock: Germany-based high-temperature thermal energy storage company for industrial and district heat customers. Closest European direct competitor to Caldera in modular thermal storage.
- Antora Energy: US-based developer of thermal batteries for industrial heat and power using carbon block storage. Directly competes with Caldera in electrified industrial heat storage for the same customer verticals.
- Electrified Thermal Solutions (ETS): US-based developer of the Joule Hive thermal battery for industrial process heat decarbonization. Competes head-to-head with Caldera for electrified industrial heat customers.
- Rondo Energy: US-based industrial heat battery company delivering high-temperature stored heat to heavy industry. Closest analog to Caldera's Storage Boiler in technology, customer base, and decarbonization pitch.
- EnergyNest: Norway-based thermal battery provider for industrial heat decarbonization using modular concrete-based storage. Comparable technology positioning and industrial customer focus.
Broad incumbents
- GEA Group: Global industrial systems supplier for food, beverage and pharmaceutical sectors; Caldera's lead Series A investor and channel partner. Offers heat pumps and process heating equipment that sit adjacent to — and could partly substitute for — Caldera's storage boilers.
- Bosch Industriekessel: Established European manufacturer of industrial boilers and steam systems with deep installed base in food, beverage and pharma. Sets the incumbent standard that Caldera's electric Storage Boiler must displace.
- Siemens Energy: Global broad-line energy and industrial equipment supplier with capabilities across power generation, industrial heat and decarbonization solutions. Large incumbent competing for industrial heat decarbonization budgets.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat5 records
Key risks6 records
Key highlights7 records
Customer concentration
Caldera social profiles
Digital presenceCaldera compliance and trust
Trust signalCompliance3 records
Caldera financial estimates
Financial estimateRevenue estimate
Valuation estimate
Caldera leadership team
Management profileNumber of profiles
Profiles10 records
Caldera funding detail
Funding detailFunding overview
Funding rounds3 records
Investors3 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Caldera M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Caldera
What does Caldera do?
Caldera designs, manufactures, and sells industrial-scale electric Storage Boilers that combine an electric/electrode boiler with integrated thermal storage using proprietary Heat Cells (recycled aluminium and volcanic rock composite in vacuum-insulated chambers). The systems convert renewable or grid electricity into stored heat and deliver process steam up to 16 bar (~204°C) or hot water on demand for industrial customers in brewing, distilling, food processing, pharmaceuticals, paper, and healthcare. Configurable modular storage capacity from 5 MWh to 100+ MWh, sold as turnkey installations alongside site assessment, system design, and project execution services.
Is Caldera a public or private company?
Caldera is a private company. It is classified as venture growth investor backed and is currently operating.
When was Caldera founded?
Caldera was founded in 2017. It employs 11 to 50 people.
Where is Caldera based?
Caldera is headquartered in Fareham, United Kingdom, in the Europe region.
How does Caldera make money?
Three revenue lines are on record. Electric Storage Boiler Sales are the primary driver. The others are solar Developer OEM Supply and engineering & Project Services.
Who are Caldera's main competitors?
Direct peers on record are Malta Inc., Brenmiller Energy, Kraftblock, Antora Energy, Electrified Thermal Solutions (ETS), Rondo Energy and EnergyNest. Broad incumbents are GEA Group, Bosch Industriekessel and Siemens Energy.
Does Caldera have an API?
No public API is recorded for Caldera.
What industry is Caldera in?
Caldera's product category is Industrial Thermal Energy Storage Equipment. Its primary akta.pro industry code is IMAHAKAD, Boilers, Furnaces & Process Heating Equipment, with a secondary code of EUAFADAC, Thermal LDES (High-Temperature, Molten Salt, Carnot/Heat-to-Power). Its NAICS code is 33241 and its SIC code is 3433.