COMPANY PROFILE / NEXT-GEN ENERGY STORAGE
Invinity Energy Systems
A U.K. AIM-listed maker of vanadium redox flow batteries (VFBs) built in the U.K. and Canada and through partners: deliveries are accumulating, but losses continue and cash has fallen
Invinity Energy Systems comes up in any discussion of next-generation storage because it is one of the few companies that has delivered the vanadium flow battery, which uses an aqueous electrolyte containing vanadium ions, as a standardized factory product to many places around the world. Its 2025 annual report, published in June 2026, says it has delivered more than 2,000 batteries, that the energy discharged by customers' systems has reached 9.0 GWh (11 GWh in the September 2026 interim announcement), and that 2025 revenue was £8.2 million, or £17.8 million with U.K. government project grants added. On the other hand, gross loss for 2025 was £2.9 million, the pre-tax loss was £24.1 million, the loss for the first half of 2026 was £12.1 million, and cash fell from £28.8 million at the end of 2025 to £10.5 million at the end of June 2026. This profile follows the company's official disclosures, such as the annual report and the interim announcement, as written, setting out what the company has put in, what is progressing and what cannot be confirmed, in a neutral way. It is not an assessment of the company's financial condition or technology.
- Invinity Energy Systems in 30 seconds, and where it stands in next-generation storage
- The logo and how the name is written
- Where the company sits in the field
- Scale
- Resources committed to next-generation storage
- What it has done so far
- What comes next
- What the company is aiming for in next-generation storage
- Map of partnerships in next-generation storage
- Technologies, products and services
- The risks this company carries
- Glossary, references and claim-to-source audit
1. Invinity Energy Systems in 30 seconds, and where it stands in next-generation storage
(sales and IR)Design and manufacturing in Bathgate and Motherwell (Scotland) and Vancouver (Canada); sales and customer support in California
Invinity Energy Systems is a company whose disclosures show a delivery and operating record alongside losses and falling cash Sourced. According to the company, it has delivered more than 2,000 batteries, and the energy discharged by customers' systems reached 11 GWh. First-half 2026 orders were 34.2 MWh (11.7 MWh in the same half of 2025), the firm order book exceeds 77 MWh (for delivery in 2026-2028), and a 43 MWh order in the U.S. (its largest) was announced in August 2026, along with a design contract for up to 1.5 GWh in Switzerland in May. On the other hand, revenue has swung widely, from £22.0 million in 2023 to £5.0 million in 2024 and £8.2 million in 2025, and first-half 2026 revenue was small at £1.1 million. The company says revenue recognition in 2026 is expected to be heavily weighted to the second half. The annual report and interim announcement also say that the directors judge that the going-concern basis is appropriate, while they expect that additional funding will be needed for expansion Sourced. This profile keeps the record in figures, orders and plans, and finances separate, as the company's materials present them.
2. The logo and how the name is written
A note on names: the legal entity is Invinity Energy Systems plc (shortened to "Invinity"). Its predecessors were Camco Clean Energy and redT energy plc, and the name was changed in 2020 (company filings). The battery product names are the current Endurium (large-scale) and Endurium Enterprise (commercial and industrial), and the previous generation VS3 (all company names). The logo image (SVG) was taken from the one served by the company's official website (invinity.com).
Official site: https://invinity.com/3. Where the company sits in the field
Invinity Energy Systems falls under the "long-duration & new chemistries" type. The annual report describes its business as the manufacture and sale of vanadium flow batteries, with three sources of revenue: battery sales, service and warranty, and licence and royalty agreements Sourced. In practice, battery modules (Endurium, 340 kWh) are packaged as container-format units and combined into configurations from a few megawatt-hours up to gigawatt-hours. Its approach to manufacturing is a mix of its own plants (U.K. and Canada) and partner manufacturing (China, the U.S. and elsewhere), which the company calls a "low-capex, partnership-led manufacturing model". The strengths one would expect in this type are the company's "no thermal runaway mechanism" and "long life", and the weakness one would expect is "limited manufacturing scale and the need to respond on price" Our calculation (the categories and axes of assessment are our own framing, not the company's self-assessment). Others of the same long-duration type include Form Energy (iron-air), Eos Energy Enterprises (zinc-based) and ESS Tech (iron flow).
4. Scale
The fiscal year runs January to December and amounts are in pounds sterling (£). The figures below are from the annual report for 2025 and the interim results announcement for the first half of 2026 Sourced.
| Indicator (£ million) | Year to Dec 2023 | Year to Dec 2024 | Year to Dec 2025 | First half 2026 [prior-year half] |
|---|---|---|---|---|
| Revenue | 22.0 | 5.0 | 8.2 | 1.1 [0.3] |
| Project grants | 0.3 | - | 9.1 | 0.6 [0.6] |
| Revenue and project grants (company's measure) | 22.3 | 5.2 | 17.8 | 1.7 [0.9] |
| Gross profit / (loss) | (3.3) | (3.5) | (2.9) | (0.7) [(1.9)] |
| Adjusted EBITDA | (22.3) | (19.3) | (20.6) | (10.6) [(9.1)] |
| Pre-tax loss / loss for the period | (23.2) | (22.8) | (24.1) | (12.1) [(10.6)] |
| Cash flow from operating activities | - | (24.9) | (17.2) | (12.9) [(12.3)] |
| Cash (net cash) | 5.0 | 32.4 | 28.8 | 10.5 [18.7] |
| Other indicators | Value | As of |
|---|---|---|
| Sales and shipments (MWh) | Orders in 2025 of 31.4 MWh (5.2 MWh in 2024), shipments of 24.9 MWh (7.3 MWh) and an average deal size of 4.5 MWh (2.6 MWh). Orders in the first half of 2026 were 34.2 MWh (11.7 MWh in the same half of 2025) | Year to Dec 2025 / first half 2026 |
| Order book (company's wording) | Signed unconditional contracts of more than 77 MWh (for delivery in 2026-2028). Expected revenue from them: £11 million in 2026, £25 million in 2027, £5 million in 2028 (company outlook) | September 2026 |
| Projects and track record | More than 2,000 batteries, about 100 projects in 17 countries, and cumulative discharge since 2022 of 11 GWh (September 2026). The 2025 annual report said 9.0 GWh and more than 90 projects | September 2026 / May 2026 |
| Major shareholders (share of issued capital) | U.K. National Wealth Fund 19.11%, Atri Energy Transition 11.27%, Next Gen Mobility 11.27%, Schroders 9.97%, Janus Henderson 5.31%, Artha Global Opportunities Fund 3.94% | 30 April 2026 |
| Revenue breakdown (2025) | By region: Europe £6.18 million, Asia £0.96 million (royalties), North America £1.00 million, Australia £0.04 million | Year to Dec 2025 |
The figures above are the company's disclosed figures set side by side, not an assessment of financial condition. What the company calls "revenue and project grants" includes grants from the U.K. Department for Energy Security and Net Zero (DESNZ) (£9.1 million in 2025), so it is not revenue itself. The company puts the 2025 gross margin at -35% (-70% in 2024). The annual report and interim announcement say that the directors prepared cash forecasts to June 2027 (including a downside case that excludes unsigned pipeline contracts) and expect the company to remain cash positive during the period without further fundraising. However, the forecast assumes deferred capital expenditure and lower operating costs, and the directors expect that additional funding would be needed for expansion and for the period beyond. Against cash of £10.5 million at the end of June 2026, first-half operating cash flow was -£12.9 million. The company itself lists funding risk as a "high likelihood, high impact" item.
5. Resources committed to next-generation storage
The whole of Invinity is a vanadium flow battery business, so company-wide figures are almost entirely figures for next-generation storage. However, total capital expenditure and the latest manufacturing capacity (GWh a year) could not be confirmed.
| Type of resource | What primary sources confirm | Status |
|---|---|---|
| People | 180 employees (September 2026). The 2025 average was 162 (Canada 87, U.K. 66, U.S. 9) and 145 in 2024. 83 patents granted or pending. The company cites more R&D staff as a reason for the higher first-half 2026 loss (+£0.8 million in staff costs) | Sourced |
| Money (R&D and facilities) | R&D costs were £1.78 million in 2025 (£2.42 million in 2024), with £1.42 million offset by R&D recoveries, tax credits and grants. Capital expenditure and related prepayments were £17.0 million in 2025 (partly offset by £7.5 million of grants received for Copwood), including the purchase and commissioning of a semi-automated stack production line. First-half 2026 investing outflows were £5.0 million (mainly completing Copwood) | Sourced |
| Acquisitions, investments, joint ventures and divestments | (1) Equity raised: on 30 September 2025, £25 million of new shares (128,205,128 shares), subscribed by Atri Energy Transition (India) and Next Gen Mobility. (2) Licensing and manufacturing partnerships: UESNT, C&D Inc. (China), International Resources Limited (Hong Kong) and Atri Energy (India). (3) Associates: Vanadium Electrolyte Rental Limited (50%, for vanadium procurement) and Invinity (HK) Limited (20%). (4) No divestment or new joint venture was found | Sourced |
| Universities, research institutes and public funding | U.K. government (DESNZ): a £10 million grant under the LoDES program for Copwood (£0.3 million recognized in 2023, £9.1 million in 2025 and £0.6 million in 2026). U.S. Department of Energy: supports the PNNL (12 MWh) and Dairyland (43 MWh) projects. California Energy Commission: supports projects such as PSG (32 MWh). Universities: in 2025 a research collaboration with the University of Strathclyde's chemistry department on vanadium electrolyte. U.K. National Wealth Fund: a shareholder with about 19% | Sourced |
| Investments in start-ups | Could not be confirmed | Not confirmed |
Next come the manufacturing sites and main projects. Stages are in the wording of the company's announcements, and plans and targets are Not yet confirmed.
| Manufacturing site | Location | Description (company statements) | Stage | Date | Source |
|---|---|---|---|---|---|
| Own plants | Bathgate and Motherwell, Scotland; Vancouver, Canada | Design, manufacturing and assembly. A semi-automated stack production line was bought and commissioned in 2025. A December 2024 company document said "close to 1 GWh of annual production capacity" | Operating. The latest annual capacity could not be confirmed | Year to Dec 2025 | Reference 1, 6 |
| Partner in China | Suzhou (Suzhou Baojia) | Shown on the company's manufacturing map. A partnership with UESNT and C&D Inc. | Partnership stage. Output could not be confirmed | September 2026 | Reference 3 |
| New U.S. plant | U.S. (site not disclosed) | Planned to make the batteries for Dairyland (43 MWh) and PSG (32 MWh); "on track to be established by year end" | Plan (Not yet confirmed). Deliveries from 2027 | August-September 2026 | Reference 2, 3 |
| Project | Location | Size | Stage (in the announcements' wording) | Date | Source |
|---|---|---|---|---|---|
| Copwood VFB Energy Hub | Uckfield, East Sussex, U.K. | 20.7 MWh (VS3), 3 MWp of solar, 3 to 18 hours | Battery delivery complete. Grid connection is still to be completed (the company expects connection in late 2026); commissioning and first revenue follow | 2025 annual report; September 2026 | Reference 1, 2, 3 |
| FlexBase Group, Technology Centre Laufenburg | Laufenburg, Switzerland | 1.5 GWh initially (0.6 GW), 2.1 GWh in a second phase; co-located with a data center (500 MW) | Invinity has a design (engineering-phase) contract. Selection announced on 21 May 2026; EPC agreement with Equans Switzerland in August. The delivery phase is from 2027 | May and August 2026 | Reference 2, 3, 11 |
| Dairyland Power Cooperative | U.S. Midwest | 43 MWh (Endurium); the company's largest order | Sale announced on 3 August 2026. Funded under the DOE's REVIVE program. Deliveries from late 2027, from the new U.S. plant | August 2026 | Reference 10 |
| Pacific Steel Group, Mojave Micro Mill | California, U.S. | 32 MWh (Endurium), 40 MWp of solar | Contract. Funded by the California Energy Commission. Deliveries from 2027 | 2026 | Reference 3 |
| PNNL (U.S. Department of Energy) | Washington State, U.S. | 12 MWh (Endurium) | Contract (company's list of customer sites). The interim presentation mentions it as a delivery planned for the second half of 2026 | 2026 | Reference 2, 3 |
| U.K. LDES Cap and Floor | U.K. | The 2025 report said bids for 16.7 GWh across 21 projects secured eligibility. The September 2026 interim says Frontier Power's "Legacy" project was selected to progress in Window 1, expected to include up to 260 MWh of Invinity batteries | In June 2026 Ofgem published a consultation on its minded-to decisions for Window 1. A final decision could not be confirmed | June-September 2026 | Reference 1, 2, 7 |
According to the company, a VFB charges and discharges purely through changes in the oxidation state of ions in an aqueous electrolyte containing vanadium, with no metal deposited on a solid electrode, so "no dendrites or plating occur" Sourced (company website). The annual report says vanadium makes up about two-thirds of the value of the electrolyte, and the electrolyte a quarter to a third of the landed cost of a battery, so a 5% change in the vanadium price changes the value of the electrolyte by about 3%. Vanadium is used mainly to strengthen steel, and the report also says it is not a mature market in which prices can be locked in with futures or the like. Where materials matter, then, are (1) vanadium sourcing and price: Invinity holds a 50% stake in an associate for vanadium procurement (Vanadium Electrolyte Rental Limited). (2) Electrolyte composition and life: a research collaboration with the University of Strathclyde on vanadium electrolyte in 2025. (3) The stack's membrane and electrodes: product specifications are not published. The company states a "30+ year life", "no capacity degradation" and "20,000+ deep discharge cycles", but these are manufacturer's stated values and no test conditions (temperature, depth of discharge, rate) could be confirmed. The company says DNV, an independent assurance firm, carried out "bankability" studies (whether lenders can readily finance the technology) in 2022 and 2024 and issued product validation reports in 2025, but we could not confirm the reports themselves. See also our explainers on redox flow batteries and on long-duration storage (iron-air and zinc-based).
6. What it has done so far
| When | What happened | Why it matters |
|---|---|---|
| 2020 | redT energy plc changed its name to Invinity Energy Systems (April 2020 change-of-name filing). Design and manufacturing are in Scotland and Canada | The start of operations under the current name |
| 2022 and 2024 | DNV carried out "bankability" studies of the product (company statement) | External validation aimed at lenders (reports could not be confirmed) |
| 2023 | Revenue of £22.0 million. Became a recipient of the £10 million DESNZ LoDES grant (total), with £0.3 million recognized | Very different from revenue from 2024 on |
| August-December 2024 | August: the first Endurium was manufactured (the starting point for cost reduction). November: shareholders were sent documents on moving the parent from a Jersey company to a U.K. company (redomiciliation). A December company document described Endurium as "recently launched" | A change of product generation |
| 9 January 2025 | The parent was moved to a U.K. company (a one-for-one share exchange) | Simplifying the structure |
| March 2025 | At La Plana in Spain (V-ION), ABB Renewable Energy (formerly Gamesa Electric) tested the first Endurium (1.2 MWh) | Field testing by an outside party |
| September 2025 | Launched Endurium Enterprise. On 30 September, £25 million of new shares subscribed by Atri Energy Transition and Next Gen Mobility | Commercial and industrial offering; funding and the Indian market |
| October-December 2025 | The company says bids for 16.7 GWh (21 projects) secured eligibility in the U.K. LDES Cap and Floor. In December, the first sale of Endurium Enterprise (a French aquaculture business) | Taking part in policy-driven projects |
| September 2025-January 2026 | Widened relationships with partners in China, Hong Kong and India (signing in China in September 2025; exhibiting at India Energy Week in January 2026) | Regional manufacturing partnerships |
| 21 May 2026 | Announced it had been selected to design a VFB of up to 1.5 GWh for FlexBase Group's Technology Centre Laufenburg in Switzerland | The first GWh-scale project announced |
| June 2026 | Published results and the annual report for 2025 (results presentation in early June) | As disclosed |
| August 2026 | 3 August: a 43 MWh order from Dairyland Power Cooperative. 11 August: an EPC agreement with Equans Switzerland for the FlexBase project. The company announced cumulative discharge of 10 GWh | Large U.S. and European projects |
| September 2026 | 21 September: interim results. Cumulative discharge of 11 GWh, and an order book of more than 77 MWh. Chair Neil O'Brien announced his intention to retire (a successor is being sought). Volker Beckers became a non-executive director | A change in the board |
7. What comes next
These figures are company targets and expectations, not results Not yet confirmed. The official materials also contain the following plans.
- Copwood: complete grid connection, then commissioning and first revenue (connection expected in late 2026)
- U.K. LDES Cap and Floor: Ofgem's final decision for Window 1 could not be confirmed. Invinity batteries are expected to be up to 260 MWh in Frontier Power's "Legacy" project
- Frameworks (signed MoUs and master agreements) are 0.8 GWh and the development pipeline is 11.8 GWh (company metrics: not orders, and with different levels of certainty). The company's revenue outlook shows £157 million from frameworks and £71 million (risk-weighted) from the development pipeline in 2028
- Funding: the directors expect that additional funding will be needed for expansion and for the period after June 2027 (annual report and interim announcement)
- The chair: a successor to Neil O'Brien is being sought
Published round-trip efficiency or energy-density figures for Endurium; specifications of the stack's membrane and electrodes; the latest annual capacity (GWh) of each manufacturing site; the site and investment for the new U.S. plant; a delivery-phase contract and its value for FlexBase; Ofgem's final decision for Window 1 of the U.K. LDES Cap and Floor; the text of DNV's reports; the latest funding plans (after the September 2026 interim announcement). None of this appears in the annual report, interim announcement or website reviewed.
8. What the company is aiming for in next-generation storage
We separate what the company says directly from what we read into it. Inference marks an interpretation of ours drawn from primary information.
| What we read from it | Primary information behind it | Status |
|---|---|---|
| The aim is "to move from technology leader to a commercially scaling energy storage business" | The September 2026 interim presentation says "Invinity is transitioning from technology leader to commercially scaling energy storage business". The strategy in the annual report lists winning LDES projects, growing in commercial and industrial and data centers, scaling manufacturing, and reducing cost | Sourced (company statement) |
| The top priority for now appears to be reducing product cost | The company says it is running 18 months ahead of expectations on a 66% cost reduction for Endurium against VS3, and targets upfront cost competitive with lithium-ion by 2030 | Sourced / Inference (priority) |
| Manufacturing is to be spread through regional partner manufacturing | The annual report cites a "low-capex, partnership-led manufacturing model" through partnerships with UESNT, Atri and C&D, and meeting local-content requirements in each region. A new U.S. plant is also planned | Sourced |
| Uses are widening to policy-driven LDES projects, data centers and industry | The U.K. Cap and Floor, projects funded by the U.S. DOE and the California Energy Commission, and the FlexBase project co-located with a data center in Switzerland | Sourced / Inference (a trend) |
The reading that "uses are widening to policy-driven LDES projects and data centers" rests on where the funding for the large projects of 2025-2026 comes from. Of the projects announced, Dairyland (43 MWh) is supported by the U.S. Department of Energy's REVIVE program, Pacific Steel Group (32 MWh) by the California Energy Commission, and Copwood (20.7 MWh) by a £10 million DESNZ grant Sourced. The largest, FlexBase (1.5 GWh initially), is planned to sit alongside a data center and technology campus, and the contract at present is for design Sourced. We therefore read this as the company's large projects depending on public funding and policy frameworks, and on data-center power demand Not yet confirmed. This is our interpretation, not a policy the company has stated. The company itself lists dependence on grants and public procurement as a "high likelihood, high impact" risk.
9. Map of partnerships in next-generation storage
What stands out in Invinity's partnerships is that the providers of capital (the U.K. National Wealth Fund, Atri Energy and Next Gen Mobility) are also large shareholders and partners in opening markets Sourced. The National Wealth Fund holds about 19%, and Atri Energy and Next Gen Mobility about 11% each. The company says the £25 million share issue of September 2025, subscribed by the latter two, was tied to opening up commercial opportunities in India. In manufacturing it is widening partnerships with regional partners such as UESNT and C&D Inc. (China). On the other hand, the names of individual suppliers of cell parts (membrane, electrodes, vanadium) do not appear in the materials reviewed, and we do not speculate on this.
10. Technologies, products and services
Products are described within the annual report and the company's website. Performance values are the manufacturer's stated values; where no test conditions are given we say conditions are unknown, and we make no comparison with other companies.
| Area | What the official materials say | Note |
|---|---|---|
| Endurium (large-scale) | Configurations: 3 to 100+ MW of power, 12 to 500+ MWh of energy, 4 to 18 hours of discharge. One module is 340 kWh, and units can be stacked two or three high. 100% depth of discharge. The company states a "30+ year" life and "unlimited" cycles | Round-trip efficiency and energy-density figures could not be confirmed. The website offers a specification sheet, which we did not check |
| Endurium Enterprise (commercial and industrial) | Configurations: 1 to 20 MW, 4 to 80 MWh, 3 to 18 hours. Launched in September 2025; first sale in December | For behind-the-meter use |
| VS3 (previous generation) | Configurations: 0.7 to 10 MW, 2 to 40 MWh, 2 to 12 hours. The core of the delivered fleet. Target of cutting unit cost of Endurium by at least 66% against VS3 (company) | Most deliveries to date, such as Copwood's 20.7 MWh, are VS3 |
| Performance the company states (manufacturer's stated values) | 20,000+ deep discharge cycles, no capacity degradation, a 30+ year life, and no dendrite formation (company statements). Non-flammable; the electrolyte is aqueous. Field testing at La Plana by ABB, and DNV product validation reports (company statements) | All are manufacturer's stated values; no test conditions (temperature, DoD, rate) could be confirmed |
| Services and licensing | Installation and commissioning support, remote monitoring and optimization, and licence and royalty agreements (royalty income of £0.96 million in 2025) | Battery sales are the main source of revenue |
| Standards and certification | No test results such as UL 9540A could be found in the annual report or website | No certificate or test report could be confirmed |
A VFB uses ions of the same element (vanadium) in different oxidation states on the positive and negative sides, so it is generally explained that even if the electrolyte mixes across over the years, in principle it can be rebalanced and used on Not yet confirmed (a general statement, not a description of Invinity's design). The company says there is "no capacity degradation", but the replacement cycles and costs of the membrane, stacks and pumps could not be found in the materials reviewed. The annual report records, at the end of 2025, a warranty provision of £0.2 million and a provision for contract losses of £2.2 million (£2.4 million of provisions in total), and explains that these relate to servicing legacy systems and higher shipping costs for deliveries to two remote sites Sourced. It also lists as risks the earlier reliance on single sources for some parts (cut from 20% of the battery to 1%, the company says) and the volatility of the vanadium price. See also our explainers on redox flow batteries and on cell evaluation and degradation.
11. The risks this company carries
| Risk | Detail | Status |
|---|---|---|
| Funding and falling cash | Cash fell from £28.8 million at the end of 2025 to £10.5 million at the end of June 2026, with first-half operating cash flow of -£12.9 million and a loss of £12.1 million. The company rates funding risk as high likelihood and high impact. The directors forecast that cash remains positive to June 2027, and expect additional funding to be needed for expansion and beyond | Sourced |
| Swings in revenue and a second-half weighting | Revenue was £22.0 million in 2023, £5.0 million in 2024 and £8.2 million in 2025, and £1.1 million in the first half of 2026; the full year is expected to be heavily weighted to the second half (depending on delivery timing) | Sourced / Not yet confirmed |
| Converting orders into deliveries and revenue | Projects depend on third parties, including a developer's financial close (the company rates "multi-party project risk" high and high). FlexBase is at the design stage. The company says frameworks and the pipeline carry lower certainty | Sourced |
| Dependence on public funding and policy | Grants and public procurement are rated high likelihood, high impact. In 2025 grants of £9.1 million were about 51% of revenue and grants combined (£17.8 million) Our calculation. Ofgem's final decision on the U.K. LDES Cap and Floor could not be confirmed | Sourced / Not yet confirmed |
| Bankability | The company says lenders are slow to engage until a technology is "established" (high and high). It plans to share Copwood's operating data with lenders | Sourced |
| Price competition and supply chain | Price competition from lithium-ion batteries, single-sourced parts (cut from 20% to 1%), the vanadium price (a 5% change moves the electrolyte's value by about 3%), and tariffs | Sourced |
| Scaling manufacturing and overseas sites | A new U.S. plant (expected by the end of 2026) and manufacturing with partners in China and India. The company rates the risk of IP transfer as low likelihood and medium impact | Sourced / Not yet confirmed |
| Changes in management | The chair intends to retire (a successor is being sought). Directors changed in 2025. The CEO and CFO remain in post | Sourced |
| Difficulty of outside verification | Performance values on life, degradation and efficiency are manufacturer's stated values, with no test conditions published. The text of DNV's reports could not be confirmed in public materials | Not yet confirmed |
This profile summarizes a company and is not advice on the design, installation or safety of batteries or storage facilities. Installing and operating storage equipment is subject to national and local laws, standards and operators' safety rules.
12. Glossary
- Vanadium flow battery (VFB)
- A battery in which an electrolyte containing vanadium ions is kept in outside tanks and pumped through the stack for charge and discharge. Both the positive and negative sides use differences in the oxidation state of vanadium.
- AIM
- The London Stock Exchange's market for growing companies. Invinity's shares trade on AIM under the symbol IES.
- RNS (Regulatory News Service)
- The London Stock Exchange's official channel through which listed companies publish important information.
- LDES Cap and Floor
- A U.K. scheme for long-duration storage. If revenues fall below a floor, consumers top up the difference through bills; if they exceed a cap, the excess goes back to consumers (Ofgem's description).
- LoDES
- DESNZ's Longer Duration Energy Storage demonstration program. Invinity's Copwood project received a £10 million grant under it.
- Bankability
- The degree to which lenders judge that a project using a technology can readily be financed.
- EPC
- A contract covering engineering, procurement and construction as a package.
- VS3 / Endurium / Endurium Enterprise
- Generations and types of Invinity's batteries: VS3 is the previous generation, Endurium the current large-scale product and Enterprise the commercial and industrial version.
- Order book / frameworks / development pipeline
- The company's categories: signed unconditional contracts / signed MoUs, master agreements and similar / projects in a procurement process. Certainty falls in that order.
- DNV
- An independent technical assessment and certification body. The company says it carried out studies of Invinity's product (2022 and 2024).
13. References
- Invinity Energy Systems 2025 Annual Report & Financial Statements (year to 31 December 2025; published June 2026; PDF). Business overview, finances, risks, major shareholders, grants, the Copwood case study. https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf
- Invinity Energy Systems 2026 Interim Results (interim announcement for the six months to 30 June 2026; RNS of 21 September 2026, as posted by Investegate). https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784
- Invinity Energy Systems 2026 Interim Results presentation (22 September 2026; PDF). Projects, manufacturing sites, cost reduction, pipeline, finances. https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf
- Invinity Energy Systems Company website, 'Vanadium Flow Batteries'. Product range (Endurium, Endurium Enterprise, VS3) and stated specifications. https://invinity.com/vanadium-flow-batteries/
- Invinity Energy Systems Company website, 'Vanadium Flow Battery Lifespan'. Stated life and degradation. https://invinity.com/vanadium-flow-battery-lifespan/
- Invinity Energy Systems Company document (factsheet, December 2024; PDF). Annual capacity, Endurium, partners. https://invinity.com/wp-content/uploads/2024/12/Invinity_factsheet_Dec24.pdf
- Office of Gas and Electricity Markets (Ofgem) U.K. Office of Gas and Electricity Markets (Ofgem), 'Long duration electricity storage' page. The LDES cap and floor scheme and the consultation on Window 1 minded-to decisions. https://www.ofgem.gov.uk/energy-policy-and-regulation/policy-and-regulatory-programmes/long-duration-electricity-storage
- Invinity Energy Systems Company website home page (source of the logo image; product range; company overview). https://invinity.com/
- Invinity Energy Systems Company website, 'Shareholder Documents'. Annual reports, shareholder notices and redomiciliation documents. https://invinity.com/investors/shareholder-documents/
- Invinity Energy Systems RNS '43 MWh Sale to U.S. Power Cooperative' (3 August 2026). The Dairyland Power Cooperative order. https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/43-mwh-sale-to-u-s-power-cooperative/9699759
- Invinity Energy Systems RNS 'Progress on FlexBase Project Delivery' (11 August 2026). The EPC agreement with Equans Switzerland. https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/progress-on-flexbase-project-delivery/9714407
14. Claim-to-source audit
| Claim in the text | Status | Source |
|---|---|---|
| Legal name, U.K. company, the parent's move to the U.K. (9 January 2025), AIM listing (IES), December year-end, the business and its three sources of revenue | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 9 https://invinity.com/investors/shareholder-documents/ |
| Revenue, project grants, gross loss, adjusted EBITDA, pre-tax loss, net cash, operating cash flow, capital expenditure and the breakdown of grants for 2023-2025 | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf |
| Revenue, grants, gross loss, adjusted EBITDA, loss for the period, cash flows, cash, inventory and balance sheet for the first half of 2026 | Sourced | Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf |
| Orders (31.4 MWh in 2025; 34.2 MWh in the first half of 2026), shipments, average deal size, the order book of more than 77 MWh, frameworks of 0.8 GWh, the pipeline and the revenue outlook (11, 25 and 5 million) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf |
| Employees (180; a 2025 average of 162), 83 patents, about 100 projects in 17 countries, more than 2,000 batteries, 11 GWh discharged (September 2026), 9.0 GWh (May 2026) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf |
| Major shareholders' shares (30 April 2026) and the £25 million share issue of 30 September 2025 (128,205,128 shares) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf |
| Copwood (20.7 MWh, VS3, the £10 million DESNZ grant, delivery complete, grid connection still to come) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf |
| FlexBase Group (1.5 GWh initially, 2.1 GWh in a second phase, a design contract, selection on 21 May 2026, the EPC agreement with Equans Switzerland) | Sourced | Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf Reference 11 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/progress-on-flexbase-project-delivery/9714407 |
| Dairyland Power Cooperative 43 MWh (the DOE's REVIVE program; deliveries from late 2027), PSG 32 MWh and PNNL 12 MWh | Sourced | Reference 10 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/43-mwh-sale-to-u-s-power-cooperative/9699759 Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 |
| The U.K. LDES Cap and Floor: 21 projects and 16.7 GWh secured eligibility in 2025; up to 260 MWh in Frontier Power's project; Ofgem's consultation on minded-to decisions (June 2026) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 7 https://www.ofgem.gov.uk/energy-policy-and-regulation/policy-and-regulatory-programmes/long-duration-electricity-storage |
| Endurium (3 to 100+ MW, 12 to 500+ MWh, 4 to 18 hours, 340 kWh), Endurium Enterprise and VS3 configurations; stated life, cycles and depth of discharge | Sourced | Reference 4 https://invinity.com/vanadium-flow-batteries/ Reference 5 https://invinity.com/vanadium-flow-battery-lifespan/ |
| Manufacturing sites (Bathgate, Motherwell, Vancouver), the partner in China, the plan for a new U.S. plant, and close to 1 GWh of annual capacity (December 2024) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf Reference 6 https://invinity.com/wp-content/uploads/2024/12/Invinity_factsheet_Dec24.pdf |
| Vanadium as about two-thirds of the electrolyte's value, the electrolyte as a quarter to a third of landed cost, and a 5% price move giving about 3% | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf |
| The University of Strathclyde research collaboration, the associates (Vanadium Electrolyte Rental Limited, Invinity (HK) Limited) and DNV's studies (2022 and 2024) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf |
| Risks: funding, grants and public procurement, bankability, single sourcing (20% to 1%), tariffs, IP and others (the company's risk management report) | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf |
| Going concern: the directors' judgment (cash remains positive to June 2027 without further fundraising) and the expectation that additional funding will be needed | Sourced | Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 |
| The chair's intention to retire, Volker Beckers's appointment, and the names of the CEO, CFO and President (2026) | Sourced | Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf |
| Grants of £9.1 million in 2025 as about 51% of revenue and grants combined (9.1 / 17.8) | Our calculation | Our calculation (a division of figures in the company's annual report). |
| The cost-reduction target (66% for Endurium against VS3, in the first quarter of 2027), the 2030 target, and DNV's validation (company statements) | Not yet confirmed | Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 |
| Endurium round-trip efficiency and energy density, specifications of the stack's membrane and electrodes, the latest capacity, the new U.S. plant's site and investment, a FlexBase delivery contract, Ofgem's final decision on Window 1, and the text of DNV's reports | Not yet confirmed | Nothing in the materials reviewed. We make no estimate. Could not be confirmed, and we do not assert that none exists (our note). |
| The four-type classification (Cells & materials; Long-duration & new chemistries; Storage systems & operators; Recycling) and the example companies | Our calculation | Our own classification. Company names are examples from those covered in this series. |
| The general explanation that a VFB's electrolyte can be rebalanced because both sides use the same element | Not yet confirmed | General commentary, not a description of Invinity's design. |
| The readings that uses are widening to policy-driven LDES projects and data centers, and that cutting product cost is the current top priority | Inference | Our own reading (not a policy stated by the company). Reference 1 https://invinity.com/wp-content/uploads/2026/06/Invinity-Energy-Systems-plc-2025-Annual-Report.pdf Reference 2 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/2026-interims-results/9780784 Reference 3 https://invinity.com/wp-content/uploads/2026/09/2026-Interims-Presentation-22-Sept-2026-WEB.pdf Reference 10 https://www.investegate.co.uk/announcement/rns/invinity-energy-systems--ies/43-mwh-sale-to-u-s-power-cooperative/9699759 |
Last updated: 10 October 2026 / Troy Technical
The figures in this article come from Invinity Energy Systems plc's annual report for 2025, its interim results announcement (RNS) and presentation for the first half of 2026, the company's website, and a public page of the U.K. regulator Ofgem. Market-research estimates, press-report figures, and the market forecasts and third-party market-share projections that appear in the company's materials are not used. This is not an assessment of the company's financial condition or technology. Passages marked "Inference" are our own reading of primary information and are not statements by the company.