EIC Accelerator Check: Rainmaker Holland and Its Desalination Unit

Rainmaker Holland told the European Commission in 2019 that it would build, install and validate the first industrial unit of W2W, a desalination system that runs on wind and solar power without a grid connection, and that 200 units would be installed worldwide by 2025. The EU paid €2,345,474.77 of the €3,350,678.25 project, according to CORDIS. Seven years later the Rotterdam company is alive and listed on a Dutch SME exchange, but by its own account it assembles about 8 water generators a year, and most of its revenue comes from a different machine: one that condenses drinking water out of humid air.

The prototype desalination unit was tested at a desalination living lab on Gran Canaria. The project's final report says the last test phase, running on wind and solar power alone, was finished "within two months after the designated project period". No customer installation of a W2W unit built under the project has been announced.

Where Rainmaker Stands Now

The company is operating. In May 2026 the group sold share certificates to retail investors on NPEX, the Dutch exchange for small companies. The offering, described in an information memorandum dated 26 March 2026, sought up to €3.5 million in 350,000 certificates at €10. The NPEX listing page, last updated on 30 September 2026, shows 57,456 certificates issued. At the €10 issue price that is €574,560, about 16% of the maximum and above the €250,000 minimum set in the offer's key information sheet. The company register shows Rainmaker Holland B.V. as active, with balance sheets filed for 2022 to 2025, according to North Data.

What the business sells has moved away from the funded technology. The memorandum says plainly that Rainmaker Holland's revenue "consists primarily of the sale of AWG systems" (translated), its air-to-water generators, plus development work for the Dutch Ministry of Defence. Water-to-Water units are still in the catalogue, as a 3,000 litre a day WW3 and a container-based WW30 rated at 30,000 litres a day. That is well below the 150,000 litres a day the company advertised for its water-to-water range on its Netherlands Water Partnership profile. Because the lead product today is not the EU-funded desalination system, this article classes the company as pivoted.

Two Companies Called Rainmaker

The EC's list of the April 2019 winners names the beneficiary only as "RAINMAKER", Rotterdam, with the website rainmakerww.com. That website belongs to Rainmaker Worldwide Inc., a Nevada corporation based in Peterborough, Ontario, that trades over the counter in the US as RAKR. The grant went to the Dutch company, RAINMAKER HOLLAND BV, which CORDIS names as the sole beneficiary.

The two were one group when the grant was won. Rainmaker Holland was set up in 2015 as a subsidiary of Rainmaker Worldwide Inc. after a North American investor group joined, according to the NPEX memorandum. A financing round planned for 2020 failed during the pandemic, and in early 2021 the Dutch shareholders bought the business back into a new Dutch holding company. Rainmaker Worldwide's 2021 annual report describes the same deal from the other side: a restructuring signed on 31 March 2021 that eliminated $2,958,497 of its debt, left it with a 12% stake in Rainmaker Holland and made the Dutch company its principal supplier. The two sources state the stake differently: the 2026 memorandum lists Rainmaker Worldwide Inc. with 10,000 of 200,000 shares, or 5% of Rainmaker Holding B.V. before the NPEX issue. Rainmaker Worldwide continues as a separate, very small listed company; its latest filings include an August 2025 conversion of preferred shares at $0.015 a common share.

The Technology: Distilling Seawater With Wind Power

Large desalination plants mostly use reverse osmosis, which pushes seawater through a membrane at high pressure and needs steady power from the grid. W2W uses membrane distillation instead. A heat pump warms the feed water so that vapour passes through a water-repellent membrane and condenses on the cold side, leaving salt and other impurities behind. The heat can come from a compressor driven by wind or solar power, or from waste heat. The 2017 feasibility project described one unit as able to supply "more than 800 people" without a grid connection, and the company argued that thermal desalination copes better with the fluctuating output of wind and solar than reverse osmosis does.

The approach is protected. The European Patent Office granted Rainmaker Holland patent EP3947291, "System and method for purification of water by membrane distillation", on 28 August 2024, according to Google Patents. Its priority date is 3 April 2019, the day of the EIC cut-off. The memorandum lists it as one of five patented technologies held across the group and its shareholders.

The air-to-water machines that now carry the business are older. A wind-turbine-driven RainMaker that condensed about 8,000 litres a day from air was demonstrated at Leeuwarden in 2011, after a pilot running since 2008, Dutch Water Sector reported at the time. The memorandum says the technology was developed with the Dutch water research institute Wetsus, and that air-to-water output depends on heat and humidity, which limits it to warm, humid regions.

What W2W Promised, and What CORDIS Shows

The project was signed on 29 August 2019 and ran from 1 September 2019 to 31 December 2023, under the Horizon 2020 SME Instrument. The 2017 Phase 1 report had already set out "a 24-month working plan" to bring W2W to market by 2020 and named 250 units by 2024 as the goal, according to the Phase 1 reporting page. The Phase 2 objective scaled that to 200 units by 2025, a market launch in 2021 and 18 new jobs.

1. Build and validate the first W2W industrial unit, about 80 m3 a dayLateTested at the Gran Canaria living lab on grid, hybrid and off-grid power; the off-grid phase finished after the project ended. No measured daily output is published.
2. Industrial manufacturing protocolsDeliveredCompleted by the third reporting period, per the CORDIS report.
3. Protect the technologyDeliveredEP3947291 granted in August 2024.
4. Market deployment from 2021, 200 units installed by 2025Not achievedAbout 15 projects sold since 2019 and 8 generator systems a year in 2024 and 2025, mostly air-to-water.
5. 18 new jobsUnverifiedNo staff numbers are published.

The final report spends more words on what the system could be used for, from process water for green hydrogen to cooling data centres, than on what was measured. The CORDIS results page lists no publications or deliverables. The report itself says the project team "documented all efforts placed in pursuit of successful achievement of the project in face of unexpected challenges and drawbacks of the initial planning", without naming them.

What Rainmaker Has Achieved Since the Award

The company's sales are real but small and concentrated. The memorandum puts revenue from projects delivered between 2022 and 2025 at €6.5 million: Djibouti €2.2 million, Senegal €1.7 million, Defence €0.2 million and an item labelled "Horizon 2020" at €2.4 million, close to the size of the EU contribution to W2W. Its five largest customers account for more than 90% of revenue. The Djibouti and Senegal projects could not be confirmed in any independent source; earlier Senegal announcements found for this article came from Rainmaker Worldwide Inc., not the Dutch company. Invesdor's bond page instead lists initiatives in Somalia, Bali and Nigeria.

Earlier deals were announced by the North American parent. In 2017 the Dutch Ministry of Defence selected Rainmaker and the generator maker Bredenoord for a containerised water-to-water unit producing up to 25 m3 of drinking water a day for military bases, The Water Network reported. In 2018 a water-to-water unit worth $100,000 was shipped to a distributor in Jamaica, according to Dutch Water Sector. Whether either unit is still in use is not public. The memorandum describes a joint development project with the Ministry of Defence, due to end in 2027, on truck-mounted air-to-water systems and a 50 litre unit for military vehicles.

The Money

The memorandum's figures, compiled but not audited for 2023 and 2024 and internal for 2025, show revenue of €2,232,216, €2,395,187 and €2,562,631, and net losses of €266,268, €59,964 and €185,838. Cash at the end of 2025 was €588,212. Equity was €41,554 at the end of 2023, a solvency ratio of 0.6%. It jumped to €6,903,955 in October 2024, when shareholders converted their loans into shares at the same €10 million valuation later used for the NPEX offering. Most of the balance sheet is capitalised development cost: intangible assets of €7,161,736 out of total assets of €11,954,461 at the end of 2025.

Debt replaced the shareholder loans. The group borrowed through two bonds on Invesdor, at 8.75% a year for 60 months: €1,460,500 in January 2025 and €1,500,000 in November 2025, according to the memorandum. The Invesdor round pages show slightly different amounts collected, €1,481,500 and €1,596,500. The bondholders hold a first pledge on the group's receivables and movable assets, and their consent is needed before any dividend is paid.

Why Europe Should Care

Water scarcity is now an EU policy priority. The Commission's Water Resilience Strategy of 4 June 2025 says 30% of Europe's land faces water scarcity every year and sets a goal to "improve water efficiency in the EU by at least 10% until 2030". It also notes that European researchers and companies account for 40% of water technology patents worldwide. Small desalination units that run on local renewable power fit that agenda, especially for Mediterranean islands and tourist areas, the market the 2017 feasibility study targeted first.

Rainmaker's own target markets have moved away from Europe. The memorandum names remote island communities, defence and disaster relief, and eco-tourism, naming Africa and Latin America as its main markets, and Spain, Greece, Portugal and Turkey as markets it still wants to enter.

The Verdict

Rainmaker Holland has not been asked for comment for this article. Its company accounts are summarised here as reproduced in the NPEX memorandum; the filed accounts themselves were not available free of charge. All other facts come from public records and published statements, linked throughout.