Coupling electrolysers with offshore wind turbines to unlock green energy potential

Green hydrogen is poised to play a critical role in decarbonising hard-to-abate sectors of the economy. Developers are now exploring the integration of electrolysers with offshore wind farms to produce green hydrogen at sea. This innovative approach combines abundant offshore renewable energy with hydrogen versatility, accelerating the energy transition.

The concept of a green hydrogen economy to decarbonise industries is not new. However, early enthusiasm waned due to high costs and technical challenges. Despite this, green hydrogen remains a compelling solution for reducing emissions in energy-intensive sectors. While demand for hydrogen is expected to grow slowly over the next decade, analysts predict significant acceleration after 2035.

Offshore hydrogen: a big challenge, a vast opportunity

Renewable energy is key to producing green hydrogen, moving from grey or blue hydrogen to fully sustainable solutions. Offshore wind energy offers a unique opportunity to produce green hydrogen at scale, contributing meaningfully to global decarbonisation goals.

The concept is straightforward: placing electrolysers at offshore wind farms, where generated electricity is used to split water into hydrogen and oxygen. There are different electrolyser technologies – alkaline, proton exchange membrane (PEM), or solid oxide electrolysers – each with varying efficiencies, capital costs, and operational characteristics, and they can be directly coupled with floating or fixed-bottom wind turbines.

The produced hydrogen could then be either transported via pipelines or stored on-site using compressed gas or liquid hydrogen technologies and potentially converted into chemical carriers like ammonia for efficient shipping to shore. The choice of technology and system architecture will depend on various factors, including site-specific conditions, energy resource availability, and the scale of production desired.

 Producing hydrogen offshore provides access to abundant renewable energy while avoiding land-use conflicts. It also creates jobs in remote coastal areas and enhances energy security by diversifying energy sources and reducing reliance on fossil fuels.

Offshore hydrogen: making it work

Producing hydrogen offshore offers exciting possibilities, but it also presents some significant obstacles that must be overcome to ensure the feasibility and success of these projects:

• Safety Consideration: The highly flammable nature of hydrogen requires robust safety procedures for storage, transport, and handling throughout the offshore production process, adding complexity and cost.
• Specialised Infrastructure Needs: Offshore hydrogen production requires specialized ships, storage facilities, and port infrastructure. The unique properties of hydrogen, particularly its low density, necessitate expensive high-pressure or cryogenic (extremely cold) storage solutions.
• Challenges in the Marine Environment: Constructing and maintaining facilities at sea is considerably more expensive than on land. Factors such as corrosion, powerful storms, and the accumulation of marine organisms like biofouling pose constant technical and financial challenges.

While hydrogen's potential as a clean energy vector is immense, it comes with formidable challenges. Hydrogen is highly flammable, with a low ignition point and broad explosive range, which requires stringent protocols for storage, handling and transportation.

Production methods vary in their efficiency and environmental impact, and it requires specialised tankers, vessels and port infrastructure to address safety and handling issues. Its low density requires either high pressure storage or cryogenic liquefaction, which increases the costs and the risk of pressure vessel failures and cryogenic embrittlement. The lack of existing infrastructure or supply chains further contributes to the high capital costs of any hydrogen project, whether onshore or offshore.

Offshore hydrogen production adds further complexities. Infrastructure in the marine environment is inherently more expensive, with additional risks such as rapid corrosion, extreme weather conditions, and biofouling.

At ABS, with decades of experience in guiding innovators, reviewing new technologies and providing classification/certification services to the offshore industries and global shipping, we understand that these barriers are standard with new technologies. 

Despite these challenges, pioneering companies are leading the way pushing ahead with their own projects.

In Scotland, for example, Hywind Scotland, the world's first commercial floating wind farm, is exploring potential hydrogen production add-ons. Meanwhile, the AquaVentus project in Germany seeks to establish a large-scale offshore hydrogen production facility powered by dedicated North Sea wind farms, with a targeted production capacity of 10 gigawatts (GW) of green hydrogen by 2035 . This is a huge undertaking bringing together a diverse range of stakeholders, including energy companies, technology providers, research institutions, and government agencies. This collaborative approach is deemed essential to navigate the complexities of creating a robust green hydrogen infrastructure in Europe.

The immense potential of hydrogen

Despite the challenges, hydrogen represents a significant opportunity in the transition to cleaner energy systems. As a clean energy carrier, hydrogen holds immense potential. It is abundant, and its unique ability to produce only water vapour when utilised in fuel cells and combustion systems makes it a compelling solution to reduce emissions in transport and industrial applications.

Hydrogen acts as a versatile energy storage medium, capable of storing excess renewable energy electrons in molecular form and thereby helping to stabilise power grids reliant on intermittent sources like wind and solar.

There are economic benefits as well. According to the Hydrogen Council, a hydrogen economy could generate as many as 30 million jobs across the globe by 20305. Environmentally, offshore hydrogen production provides a viable pathway towards reducing greenhouse gas emissions and displacing fossil fuels in hard-to-decarbonize industrial processes and transportation sectors.

Maximising these opportunities will require continued advancements in electrolysis technology, particularly those that enhance efficiency, durability, and scalability leading in a reduction to production costs and improvement in performance. Similarly, advancements in hydrogen storage technologies, which can enable the safe and cost-effective storage of hydrogen both offshore and onshore, will be vital for integrating offshore production into the wider energy system.

Robust regulatory support

Beyond technological advancements, robust regulatory support is essential. Governments are increasingly recognizing the importance of hydrogen in their energy strategies and are expected to develop more comprehensive regulatory frameworks that foster the development of offshore hydrogen facilities.

These frameworks should include:

•  Establishing clear permitting processes,
• Implementing financial incentives and funding mechanisms,
• Developing standardised safety protocols.
• Facilitating integration not just into electricity grids and hydrogen distribution networks but also potentially blending hydrogen into existing natural gas infrastructure.

At an international level, the joint development of standardised technologies, and the establishment of collaborative research programs across borders will help to reduce costs, streamline the development process, and avoid the duplication of effort. This collaboration is also vital for guaranteeing that offshore hydrogen production is environmentally responsible, prioritising the protection of marine ecosystems and local communities.

A transformative opportunity for the transition

Offshore green hydrogen represents a transformative opportunity for the global energy transition. While challenges remain — ranging from safety concerns to high capital costs — collaborative efforts between private industry, governments, and research institutions can overcome these barriers. ABS brings decades of expertise in guiding innovators and industry stakeholders through new technologies and ensuring safety standards. By supporting infrastructure development and certification processes, ABS aims to help offshore green hydrogen achieve its potential as a cornerstone of a low-carbon future.