If there is one essential element needed to produce green hydrogen, it is water. We owe absolutely everything to this tiny molecule – from the remarkable landscapes that shape our planet to life itself. In our case, water is essential for extracting what truly matters to us, since one of its components, as it’s chemical formula H₂O suggests, is hydrogen.
By applying an electric current, we can split water into hydrogen and oxygen. Simple, quick, and sustainable, right? However, things are not quite that straightforward. Today, most electrolysers – the devices we use to produce hydrogen – rely on clean water to carry out electrolysis. And this, as you might imagine, poses a potential challenge.
Clean water, a precious resource
Clean water is a limited resource on our planet. It is estimated that only 2.5% of all water on Earth is fresh water. Of that amount, just 1% is easily accessible and usable, as most of it is locked away, frozen in glaciers (around 70%) or hidden as groundwater (about 30%).
It is curious, but the first thing that comes to mind when we think of fresh water is rivers or lakes. Sometimes, the truth is hidden or too far removed from our reality for us to understand it.
Due to its scarcity, the value of fresh water is incalculable. It is essential for human consumption, but its importance goes far beyond that. Many ecosystems depend on fresh water – rivers, lakes, and wetlands that are home to countless species. Everything is connected by water: a natural agent capable of purifying and sustaining our planet, nurturing agriculture and replenishing underground reserves.
Today, climate change poses a serious threat to fresh water resources. Global warming has led vast regions of the world into water stress, affecting food security and the health of ecosystems. Meanwhile, the melting of glaciers and other frozen fresh water reserves represents a major loss for the planet’s limited fresh water supply.
Access to water is a human right, yet it remains out of reach for more than 2.2 billion people worldwide –a quarter of the world’s population– according to the World Health Organization (WHO).
That’s why clean water and sanitation are enshrined in the UN’s Sustainable Development Goal 6. WHO also highlights key strategies to achieve this goal, including “increasing investment and capacity-building across the sector, promoting innovation and evidence-based action, improving coordination and intersectoral cooperation among all stakeholders, and adopting a more integrated and holistic approach to water management”.
A major technological challenge
By now, you might be wondering: “Alright, I get it – fresh water is important. But what does this have to do with electrolysis or this project?”
Well, at ASTERISK, we believe that what matters is not only what we do, but how we do it. For us, maintaining an ethical coherence is essential. That’s why we aim to produce renewable energy and design a system capable of doing so in a way that is viable for industry, without contradicting the challenges Europe will face in the coming years. One of those challenges is, precisely, the responsible use of water.
Over the next few years, we aim to produce green hydrogen using seawater – a much more abundant and accessible resource. Of course, like anything else, this comes with its own advantages and drawbacks. Let’s take a look at both.
- As we’ve said, electrolysis involves splitting water into its basic components – but it’s not that simple. Seawater contains other chemical elements, such as chlorine. As a result, the electrolyser produces not only hydrogen and oxygen, but also a large quantity of chlorine gas, which is corrosive and toxic. Producing chlorine is not only completely useless for our purpose, but it also damages the components of the electrolyser, which are far from cheap. Moreover, the sea contains many other substances – including microorganisms, microplastics, and much more – which can clog and hinder the system’s operation.
- However, it’s not all bad news, is it? Seawater offers enormous potential. For one, it’s almost everywhere and not at all a scarce resource. Its use opens up an important opportunity: democratising access to energy in remote locations such as islands. And when combined with other renewable systems on site – for example, tidal or wave power – it could ensure a stable and sustainable local energy supply.
An opportunity to change everything
Electrolysis using seawater is complex for many reasons. For us, that complexity is not discouraging – it’s motivating!
It pushes us to pursue our goal, which is not only scientific, but also social: to build a sustainable future that leaves no one behind, ensuring access to clean water while also guaranteeing access to energy in the most isolated parts of the world.
For all these reasons, projects like ASTERISK, driven by committed people and supported by institutions such as the European Union and the Clean Hydrogen Partnership, are exactly where such great challenges can and must be faced.
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Contact for media:
ASTERISK Press Office
Fernando Gomollón-Bel and Lucía Casas Piñeiro