Why kraftwerk TUBES' EIC Accelerator Fuel Cell Went Quiet

kraftwerk TUBES is a small Dresden company that makes tubular solid oxide fuel cells, a type of cell that turns gas into electricity at high temperature. In January 2019 the European Commission selected it, together with the Danish drone maker Sky-Watch, for an EU grant to give small fixed-wing drones "10x more flight range than LiPO battery", according to the project's CORDIS fact sheet. kraftwerk TUBES received €1,166,981.90 of the €2,485,875 EU contribution. When the project ended on 31 May 2022, "it has not been possible to produce a fully functioning hotbox with a fuel cell to fit the dimensions and weight of the drone", the final report states. No fuel cell was ever fitted into a drone.

The company's history before and after the grant is as unusual as the result. kraftwerk TUBES was registered in May 2016 at the same Dresden address as eZelleron GmbH, a fuel cell start-up that had gone into insolvency three weeks earlier after crowdfunding a pocket charger it had not delivered, according to the register entries summarised by North Data and the trade magazine H2-international. After the drone project, the company announced a fuel cell patent with Volkswagen and a target of series production in cars from 2026. Its last published accounts are for 2021.

Where kraftwerk TUBES Stands Now

kraftwerk TUBES GmbH is still registered as active at the Dresden local court, and no insolvency notice has been published, according to North Data and online-handelsregister.de. Both list the 2021 accounts, published on 8 January 2024, as the latest on record; North Data shows the 2020 accounts published later still, on 17 May 2024. No accounts for 2022, 2023 or 2024 are listed, although German law requires a limited company to submit its accounts within twelve months of the year end under § 325 of the Commercial Code. The figures in the filed accounts are behind North Data's paywall and could not be checked for this article.

The only register change since the project is a power of attorney (Prokura) granted to Christin Zimmermann in February 2022, which North Data records as revoked on 16 January 2025; online-handelsregister.de still lists February 2022 as the most recent change. No news release, job advert, product launch or customer announcement from kraftwerk TUBES itself has been found from the last 18 months. Because the register shows the company as active but the public record is otherwise silent, its status is classified here as unknown rather than active or dormant.

The group's public face has moved. The website listed for the company in the EU winner list, kraftwerkgroup.com, is now run by kraftwerk AUTO Inc. of Sacramento, California, with Sascha Kühn named as chief executive in its terms and conditions, last updated on 12 June 2025. It says its system is "Designed, built, and assembled in Dresden", calls the business "Cashflow-Positive & Independent" and "Fully bootstrapped", and claims "over $6 trillion in purchase intent from industrial partners worldwide". It does not mention drones.

Where the Company Came From

Sascha Kühn started researching small tubular solid oxide fuel cells made of nano-coated metal in 2000 and founded eZelleron in Dresden in 2008, H2-international reported in February 2021; the register shows a shelf company renamed eZelleron GmbH and moved to Dresden in October 2008, according to North Data. In January 2015 eZelleron's US arm raised more than USD 1.5 million on Kickstarter for "kraftwerk", a pocket charger that ran on lighter gas, from 11,500 supporters, the magazine reported in August 2016. The band Kraftwerk then sued over the name. The case was dismissed, but eZelleron GmbH went into insolvency: proceedings began at the Dresden local court on 18 April 2016, and the register records its liquidation on 25 April 2016.

In the insolvency, the intellectual property went to a US company, kraftwerk ASSETS, and the "fixed assets, materials, cells, design drafts and software went to kraftwerk TUBES in Germany", both owned by kraftwerk Inc., a holding Kühn set up in Silicon Valley with Martin Pentenrieder in 2016, according to H2-international. In April 2018 the magazine, citing the Dresdner Neueste Nachrichten, reported that Kühn had been charged with violating accounting rules, fraud and delaying the insolvency of eZelleron GmbH, and that prosecutors claimed he had put intellectual property in the hands of his parents. Kühn disputed this, saying the patents had only been used as collateral. The outcome of the case could not be found in any public source. The Kickstarter chargers had still not been delivered by 2021, when Kühn described the crowdfunding as a "donation to support a cause".

The Technology: Hot Tubes Instead of Platinum

Most fuel cells in cars and drones today are polymer membrane cells, which need pure hydrogen and platinum catalysts. Solid oxide fuel cells use a ceramic electrolyte and run at high temperatures, which lets them convert hydrogen and hydrocarbon gases without platinum. eZelleron's patent filings were for high-temperature fuel cells, including anode materials and a "reoxidation barrier", North Data's patent summary shows. kraftwerk TUBES describes its product as "advanced solid oxide fuel cells (aSOFCs)", and in 2021 named "unmanned aerial vehicles (UAV) and surveillance" among its markets, in its profile as a winner of the Start-up Energy Transition Award, announced on 20 October 2021.

The heat is also the difficulty. A small drone needs the cells packed into an insulated, gas-tight "hotbox" that is light enough to fly. That is where UAVEndure II failed: the final report blames the welding seams of the hotbox, which could not "withstand the conditions, when the fuel cell is in operation", and output that stayed below the target in tests.

What UAVEndure II Promised, and What CORDIS Shows

The Commission's list of winners of the 9 January 2019 cut-off of the EIC SME Instrument Phase 2, the Horizon 2020 forerunner of today's EIC Accelerator, gives the project two rows: SKY-WATCH A/S from Støvring in Denmark and KRAFTWERK TUBES GMBH from Dresden, with www.kraftwerkgroup.com as its website. The grant agreement was signed on 25 October 2019. The project ran from 1 December 2019 to 31 May 2022 at a total cost of €3,551,250. kraftwerk TUBES' part of the work was budgeted at €1,667,117, of which the EU paid €1,166,981.90, according to CORDIS. The award was grant only, and no investment by the EIC Fund in the company could be found.

The two partners had already worked together on UAVEndure I, a six-month SME Instrument Phase 1 study in 2018 for electric drones under 3 kg able to fly for up to 24 hours; Sky-Watch received its €50,000 EU contribution, kraftwerk TUBES nothing. A CORDIS search finds no other EU project for kraftwerk TUBES or eZelleron. Sky-Watch's side of the story, including its sale to a US defence group and its battery-powered drones for Ukraine, is told in a separate deep dive.

The project's final report says the work covered choosing a host aircraft and "combining the 10 stacks into the desired configuration required for providing the required output in the range of 250W". It concludes that "the project has therefore not reached a level, where it was possible to integrate the fuel cell into a drone and perform full scale tests". What the report does credit kraftwerk TUBES with is hiring: 15 new employees since the project began.

1. Fuel cell system of about 250 W in a hotbox at drone size and weightNot achievedNo fully functioning hotbox; required output not reached because of welding seam problems, per the final report.
2. Integration into a small fixed-wing drone and full-scale testsNot achievedThe report says the project never reached the point of integration.
3. "10x more flight range than LiPO battery"Not achievedNo flight test or range data published by either partner.
4. ELJUN fuel cell system on the marketNot achievedNo drone product, customer or sale announced; kraftwerkgroup.com does not mention drones.
5. Jobs at kraftwerk TUBESDelivered15 new employees reported in CORDIS; no later headcount is public.

After the Drones: A Volkswagen Patent and a Car Pitch

In November 2022, months after the drone project closed, German media reported that Volkswagen had filed a fuel cell patent together with kraftwerk TUBES. AutoBild gave the publication number as WO2022013359 and reported the company's aim to have the technology in series vehicles by 2026, with up to 10,000 units spread across several carmakers. WardsAuto said the application was filed in July 2021, while UAVEndure II was still running, and quoted Kühn: "The advantage of our solution is that it can be produced much cheaper than polymer fuel cells and it does not require any type of platinum." PC-Welt quoted him promising up to 2,000 km on one tank and a Dresden output of about 50,000 units a day. None of these reports quoted Volkswagen, and the patent registers could not be opened to check the applicants for this article.

2026 was the year series production was meant to begin. By October 2026 no carmaker had announced a vehicle with a kraftwerk fuel cell, and no supply contract had been reported. Instead, kraftwerkgroup.com lists electric cars from other brands "Upgraded by kraftwerk", with prices from 47,889 for a Kia EV6 to 2,098,889 for a Rimac Nevera (no currency is given) and ranges such as 6,302 km for a Lexus; its FAQ promises "ranges of 5,000–10,000 km" per refill. The terms say pre-orders, free or with a paid deposit of at least €1,000, are "non-refundable", "do not guarantee delivery", and depend on "external funding, including the construction of a dedicated production facility".

What Cannot Be Checked

Why Europe Should Care

The technology fits several EU priorities. The Commission's hydrogen strategy of 8 July 2020 counts on hydrogen to decarbonise transport and industry. Platinum group metals, which polymer fuel cells need and solid oxide cells avoid, are on the EU's list of critical and strategic raw materials under the Critical Raw Materials Act. And the Drone Strategy 2.0 of November 2022 aims for a large-scale European drone market by 2030, where longer endurance for small drones would matter.

A European fuel cell made without platinum would serve all three goals. But the EU money in this case went to a company whose predecessor had failed its crowdfunders, whose chief executive had been charged over that insolvency in 2018, months before the cut-off, and whose public record after the project consists mostly of claims that cannot be tested.

The Verdict

kraftwerk TUBES, kraftwerk AUTO Inc., Sascha Kühn and the EIC have not been asked for comment for this article. It is based entirely on public records, company statements, press reports and EU project data, linked throughout.