Watermeln delivers zero emission, off grid power with hydrogen – enabled by flexible composite gas storage
Watermeln provides green, zero‑emission electricity to construction sites, festivals and events where grid access is limited or unavailable. By combining hydrogen fuel‑cell generators with glass fibre composite Multi-Element Gas Containers (MEGCs) from UMOE Advanced Composites, Watermeln is able to deliver reliable, mobile power while replacing diesel generators in demanding, temporary applications.
The challenge of off‑grid power for temporary applications
Construction sites, festivals and events often require significant electrical power in locations without access to the grid, or where grid capacity is insufficient. Traditionally, these applications rely on diesel generators, which are associated with emissions, noise and local air pollution.
Watermeln was founded to address this challenge by providing clean electricity for temporary and mobile applications. However, delivering hydrogen‑based power introduces a new set of logistical requirements. Hydrogen must be sourced, transported, stored safely on site and replenished reliably, often for short‑term projects lasting days or weeks, rather than months or years.
For Watermeln, flexibility is critical. Power demand can change at short notice, and customers expect uninterrupted supply regardless of location.
About Watermeln
Watermeln is a Dutch company specializing in zero‑emission, off‑grid electricity. The company supplies hydrogen‑powered generator systems to construction sites, festivals, events and other temporary applications. Watermeln owns and operates its equipment, renting systems to customers for periods ranging from a single weekend to several months or longer.
Watermeln’s mission is to replace diesel generators with clean alternatives by making hydrogen‑based power practical, safe and cost‑effective. The company sources hydrogen from external suppliers and manages the full logistics chain to ensure reliable delivery to customer sites.
The decision: flexibility, logistics and operational control
As Watermeln scaled its hydrogen generator fleet, the company initially planned to rent hydrogen storage containers from third parties. In practice, this proved difficult. Many of the big gas companies did not offer short‑term rentals, so MEGCs could not always be guaranteed on short notice.
At the same time, hydrogen logistics represent a significant operational responsibility. Unlike diesel, hydrogen cannot be delivered instantly, and Watermeln must plan refueling in advance to ensure customers never run out of power.
To retain control over its operations and ensure flexibility for short‑term projects, Watermeln decided to invest in its own hydrogen storage containers.
Why Watermeln chose glass fibre composite MEGCs
Watermeln evaluated different technical options for hydrogen transport and storage. While higher‑pressure solutions were considered, existing filling infrastructure in the Netherlands is typically limited to around 300 bar, making ultra‑high‑pressure systems less practical for current operations.
Glass fibre composite MEGCs offered a balance well suited to Watermeln’s needs:
- Operating pressure aligned with available filling infrastructure
- Lower weight compared to steel alternatives
- Proven safety performance for hydrogen applications
- Cost‑effective for a growing, asset‑owning operator
For Watermeln, the solution needed to be technically mature and ready for deployment, rather than experimental.
The UMOE Advanced Composites solution
UMOE Advanced Composites supplied Watermeln with glass fibre composite MEGCs configured for hydrogen service. Watermeln currently operates three high‑cube MEGCs, each mounted on truck chassis and used to supply hydrogen to its generator units at customer sites.
From the outset, Watermeln worked closely with UMOE Advanced Composites on technical design, piping and instrumentation layouts, and safety specifications. This collaboration ensured compatibility with different filling locations and confidence among hydrogen suppliers when refueling the containers.
Operational performance in daily use
In operation, the MEGCs support Watermeln’s short‑term rental model by enabling hydrogen to be transported, positioned and replenished as projects evolve. Containers can be moved between sites and refilled between projects, reducing unnecessary transport distances where possible.
Watermeln tracks the environmental performance of its generator systems, comparing hydrogen‑based power with conventional diesel alternatives. Customers receive documentation showing the emissions avoided during their projects, supporting sustainability reporting and compliance requirements.
The company reports that the MEGCs have performed reliably in daily use and have met expectations in terms of handling, safety and integration with existing hydrogen infrastructure.
Working with UMOE Advanced Composites
Beyond the hardware itself, Watermeln highlights the importance of responsive technical support. As a growing company operating in a fast‑developing hydrogen market, access to experienced engineers and clear communication is essential.
“Good communication and fast technical feedback are really important for us. If we have questions, we know we’ll get clear answers quickly.”
Mark Bebingh, Hydrogen Storage Developer, Watermeln
This support has been particularly valuable when engaging with hydrogen suppliers and filling locations, where clear documentation and well‑designed systems help avoid delays.
Supporting the transition away from diesel
By combining hydrogen fuel‑cell generators with mobile hydrogen storage, Watermeln enables a practical alternative to diesel generators for temporary power applications. The MEGCs act as a flexible backbone for hydrogen supply, allowing clean electricity to be delivered wherever it is needed.
As hydrogen infrastructure continues to develop in the Netherlands and beyond, Watermeln expects its model to scale further. The collaboration with UMOE Advanced Composites provides a foundation for that growth, supporting reliable operations today while allowing flexibility for future expansion.