Water treatment for green hydrogen
Save the date! Hydrogen Technology Expo: 21 – 23 October 2025
Efficiente production with minimal water consumption
Green hydrogen - produced using the electrolysis of water with renewable energy - is a key cornerstone on the road to climate neutrality. To achieve this, Europe is currently following ambitious plans to expand production capacities and infrastructure. The challenge is to establish a clean hydrogen industry while at the same time conserving water resources.
Long-term planning security
Herco offers you a reliable supply of ultrapure water in consistent quality for electrolysers and at the same time minimises water and energy consumption in water treatment.
Sustainable solutions for electrolysis
At our site in Freiberg am Neckar, we develop and manufacture high-quality water treatment systems for pilot projects, large-scale projects and mobile container solutions. Thanks to our decades of experience in water treatment, we guarantee fast and worriless installation on site. We rely on particularly durable systems.
Top quality is sustainable
In the production process, an optimised technical design extends the service life of the electrolyser. We offer future-proof water treatment which also significantly reduces your operating costs (more on operational expenditures - OPEX) using pumps with frequency converters and an integrated concentrate stage.
High purity water extends the life of the electrolyser
"Foreign ions in the water such as iron reduce the cathode activity and thus reduce the performance of the electrolyser. At the same time, copper can increase membrane resistance."
Tugay Cerit, Product manager
Technology:
Modular components for every step in the water treatment process
1. Pre-treatment
2. Reverse osmosis
Reverse osmosis (UO)
Membrane degasser(MEG)
Electrodeionisation (EDI)
3. Storage and distribution
Pure water tank
Booster system
Mixed bed demineraliser
UV unit
4. Process water circuit
UV unit
Mixed bed demineraliser
Our portfolio
Flexible water treatment units
Our modular and scalable water treatment units are optimised for the production of green hydrogen. They cover all important steps: from pre-treatment, desalination and reverse osmosis to water storage and distribution.
Due to our extensive expertise in hydrogen applications, we develop high-quality solutions (pilot, frame and container projects) that are precisely tailored to the requirements of the electrolyser.
Our solutions
Pilot project
Frame unit
Container system
Efficient in-house engineering
Customised water treatment systems
Whether standard or customised systems - we combine proven components that are either directly available or manufactured in our facility in Freiberg am Neckar. We can supply you with standard systems up to 30 m³/h immediately; larger systems can also be realised as special systems. We would be happy to plan these together with you.
With our UP (Ultrapure) series, we offer you water treatment systems for electrolysers with an output of up to 100 MW - all from a single source. Our sustainable and durable UP series is suitable for the production of green hydrogen from well water, process water, surface water, drinking water and seawater - with suitable pre-treatment.
Case study customised system
Output and electrolysis technology
100 MW AEL
Unit technology
- Dosing system for antiscalant
- Permeate-staged reverse osmosis with electrodeionisation (20 m³/h diluate capacity)
- Membrane degassing system with side channel compressor
Premium quality that makes a difference
Solution orientated engineering
Flexible design according to your individual wishes and requirements (customised standards).
Comprehensive project management
Fast implementation of your project from standard to special solutions.
Plug & produce
systems
The system is tested thoroughly before delivery in the company's own test centre.
Sustainable water treatment
Low water and energy consumption thanks to FU pump and KR.
References:
Selection of our scalable and proven water treatment systems
UP-Container system for 20 MW (AEL)
Customer: Electrolyser manufacture, Germany
UP-Frame unit for 5 MW (PEM)
Customer: Electrolyser manufacturer, Germany
UP-Frame unit for 3 MW (AEL)
Customer: Electrolyser manufacturer, Germany
UO-Frame unit for 1 MW (AEL)
Customer: Electrolyser manufacturer, The Netherlands
UP-Container system (PEM)
Customer: Stack manufacturer, Germany
Container reference
Ultrapure water system for testing PEM stacks
REQUIREMENT
Development and construction of a complete containerised ultrapure water system for testing PEM stacks within a tight timeframe of less than 20 weeks.
SOLUTION
Herco supplies a ready-to-use solution in a 40-foot high cube container. The system has been specially tailored to the requirements of PEM stack testing and provides reliable ultrapure water treatment at the highest level.
SYSTEM TECHNOLOGY
- 40‘ high-cube-container
- Double softener
- Permeate stage ultrapure water system consisting of two
reverse osmosis stages and one electrodeionisation stage - Ultrapure water tank made of polypropylene
- UV system for the reduction of TOC
- Polisher
- IR-welded pipework
RESULT
The solution guarantees a reliable ultrapure water supply with state-of-the-art technologies. Thanks to IR welding technology, an outstanding material and process quality was achieved.
Year
2024/25
Country
Germany
Customer
Electrolyser manufacturer Germany
Branch
Hydrogen
Reference project for a 20 MW AEL electrolyser:
High-quality container system for the provision of ultrapure water for the production of green hydrogen
Performance and electrolysis technology
20 MW AEL
System technology
- 2x 40‘ high-cube-container incl. fixtures and painting (C5 and C4)
- 5,8 m³ feedwater tank
- Dual pressure booster system
- Sand filter
- Activated carbon filter
- Dosing stations
- Permeate-staged reverse osmosis with electrodeionisation (4.5 m³/h diluate capacity)
- 35 m³ diluate tank with nitrogen overlay
- UV unit with polisher
Application
For the production of green hydrogen
Customer
Electrolyser manufacturer, Germany
Reference project:
Pilot project for 5 MW PEM elektrolyser
Customer
Elektrolyser manufacturer, Germany
Performance and electrolysis technology
5 MW PEM
Unit technology
- Double softening system
- Reverse osmosis with electrodeionisation (1.5 m³/h diulat capacity)
Reference project:
Pilot project for 3 MW PEM elektrolyser
Customer
Elektrolyser manufacturer, Germany
Performance and electrolysis technology
3 MW PEM
Unit technology
- Dual pressure booster system
- Reverse osmosis (0.9 m³/h permeate capacity)
- Mixed bed demineraliser with UP resin
- Permeate tank
- Pressure booster system
Reference project:
Frame unit for 3 MW AEL electrolyser
Customer
Electrolyser manufacturer, Germany
Performance and electrolysis technology
3 MW AEL
Unit technology
- Antiscalant dosing
- Reverse osmosis with electrodeionisation (800 l/h diluate capacity)
- Diluate tank
More water treatment expertise and knowledge
Colours of hydrogen
Although hydrogen is a colourless and odourless gas, different colours appear around the future of energy production. The reason for this is that hydrogen is given different names depending on how it is produced.
Green hydrogen
In recent years, manufacturers of electrolyser around the world have recorded increasing demand and, as a result, an expansion of production capacities.
Electrolysis types: AEL, AEM, PEM, SOEC
Ultrapure water is the central raw material in electrolysis. Scalable frame and container plants produce ultrapure water for the electrolyser. Four different electrolysis technologies can be distinguished in this context.
Electrodeionisation
Electrodeionisation (abbreviated to “EDI”) or electrodialysis is a process for the continuous desalination of permeate from a reverse osmosis unit.
TOC
The TOC value (Total Organic Carbon) refers to the total amount of carbon compounds in a sample that can be attributed to organic substances.
Ultrapure water
Many water processes have special requirements for water purity and water treatment equipment.
Recent relevant articles on the topic
Hydrogen Technology Europe Expo in Hamburg 2024
Once again this year, we had a stand at the world's largest trade fair for hydrogen in Hamburg. We brought along a water treatment system for our partner Neuman & Esser.
Green hydrogen: An outlook for 2024
The production of climate-neutral hydrogen is an important cornerstone in the transformation of industry, the transport sector and the energy business
Special container solution for green hydrogen
Silke Frank (Vice President German Hydrogen and Fuel Cell Association (DWV) e.V. and Managing Director of Hydrogen Moves GmbH) visited Herco Wassertechnik GmbH...
First EMAS-certified German plant manufacturer
We are the first EMAS-certified German plant manufacturer in the water treatment sector.
The stack is a mimose.
...and what rhymes with "Mimose"? "Osmose"! What do we want to tell you now...
Made in Germany
We produce in Germany
We have many years of experience in plant construction, including complex projects. Quality ‘Made in Germany’, engineering spirit and adherence to deadlines are our top priorities. Our employees test our high-quality products in our in-house test field to ensure that they work perfectly - with factory acceptance and training on request.
Environmental management system
First EMAS-certified plant manufacturer in the water treatment sector
Herco Wassertechnik GmbH applies an environmental management system in accordance with Regulation (EC) No. 1221/2009 and EN ISO 14001:2015 (sections 4 to 10) for the continuous improvement of its environmental performance, regularly publishes an environmental statement, has the environmental management system and the environmental statement verified by an accredited, independent environmental verifier and is registered in the EMAS register (emas-register.de).
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Please feel free to contact me directly
Marcel Rückert
Business Development Manager Hydrogen
marcel.rueckert@hercowater.com
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