With the growing electrification of our energy systems combined with an increase in intermittent – or not pilotable – power generation sources, the need for energy storage solutions for power grid balancing is expected to accelerate, along with penetration rates of renewables. Similarly, the expected growth of green hydrogen uses will call for buffer storage throughout the entire value chain to ensure supply security for end-users. Leveraging its decades-long experience in steel pipes and storages, Vallourec supplies hydrogen operators with durable storage solutions for a wide range of applications.

Hydrogen storage, a great complement to batteries for large-scale and long-term energy storage

Storing energy in the form of hydrogen is an obvious solution when the end-use will also be in the form of hydrogen–an energy source which is expected to grow in a few sectors such as heavy mobility and several other industrial sectors, including former users of grey hydrogen. In addition, the use of hydrogen systems will bring further opportunities to enhance energy systems in general, providing solutions for power grid balancing. To ensure hydrogen’s worldwide success, the according storage solutions must be deployed.

"Our ambition comes with an innovative mindset and a willingness to foster collaboration in different steps of the value chain, to further improve efficiency and sustainability of energy storage systems ."

Energy-storage technologies each have their domain of validity. Batteries are best for short-term energy balancing up to a certain limit, as highly increasing the amount of energy stored brings strong constraints on costs, footprint, and access to raw materials. Conversely, storing energy in the form of molecules –typically hydrogen– offers wider opportunities for large-scale and long-term storage systems.

This is a strong asset to make the best use of already installed capacity, storing excess production when demand is low. Furthermore, it could unlock further growth of renewable sources. For example, hydrogen could boost offshore wind energy by creating a “floor price” for renewable electricity at peak production time. The combination of hydrogen’s storability with its better transportability compared to electrons, makes a solid case for offshore wind-to-hydrogen projects.

A continuum of solutions for hydrogen storage

Preferred storage technologies will depend on several factors, starting with the amount of hydrogen (or equivalent energy content) to be stored. For quantities ranging from a few kilograms up to several tons of hydrogen, the best storage options are hydrogen cylinder systems whereas quantities of up to thousands of tons of hydrogen are better stored in subsurface, in salt caverns or other geological reservoirs. For intermediate needs, it is possible to store hydrogen in liquid form, which comes with high liquefaction costs. Mid-size storages can also be to contain hydrogen in gaseous form, typically using hydrogen pipelines. With a wide range of products and steel materials, Vallourec is able to support customers in their projects whatever the amount of hydrogen to store.

Other deciding factors may relate to the structure of the supply chain, taking into consideration where hydrogen is produced (near the point of use or in a distant facility) and if or how it will be transported. Similarly, when it comes to storage in gaseous form, pressure levels are influenced by footprint constraints guiding storage capacity, and by upstream and downstream processes or uses. For instance, in mobility, storage pressures of 500 to 1,000 bar are driven by pressure levels in FCEV tanks. In this instance, Vallourec seamless pipes are commonly used for type I cylinders – often with design pressures of up to 550 bar – and proved to offer very cost-effective storage options for Hydrogen Refueling Stations.

All these factors may be project-specific and can influence the mix of storage systems. Storage or compressed hydrogen will be needed in many cases and ultimately the most cost-effective solution (in TCO) should be elected. 

Addressing the technical challenges of hydrogen containment 

Hydrogen is known to be a difficult gas to contain. For instance, its low density calls for high-pressure storage and its small-sized molecules and low viscosity create a propensity for leaks and therefore a tightly-sealed storage is needed to contain it. Moreover, hydrogen has embrittling properties on metals so the choice of material is also as crucial.

At Vallourec, we are tackling these challenges by leveraging our strong expertise and background in challenging applications. Our commitment is to develop and qualify safe, sustainable, and efficient storage solutions for our customers. Developing storage solutions for hydrogen applications is an obvious matter of safety, taking into consideration hydrogen’s hazardous properties, but it is also a matter of environmental responsibility as any leakages would produce greenhouse gas emissions and jeopardize the decarbonization effort underway.

Our R&D work over the past few years has been based on maximizing lessons learned in sour corrosion to tackle hydrogen embrittlement; undertaking qualification tests of steel materials in hydrogen service; and performing at-scale testing of our VAM® threaded connections’ tightness to hydrogen for underground storage wells. Our products are ready to contribute to a variety of hydrogen storage schemes, with an established track record in hydrogen cylinders, and recently, first references in pilot projects for underground storage.

The expert to support you in hydrogen storage

Seamless steel-based solutions are safe, cost-effective and sustainable. With lesser vulnerability to external hazards, pressure and temperature variations, they are very attractive to energy companies with strong focus on safety. In addition, low emissions during production (and strong commitments to continue progress), combined with long lifetime (several decades) and full recyclability, bring steel-based storages a genuine advantage over non-metallic alternatives like composite cylinders, especially when looking at the infrastructure’s full lifecycle.

Vallourec is committed to providing a full range of solutions for the storage of compressed-gaseous hydrogen at different scales: from ground storage in cylinders and mid-size containers to large underground storage. Our ambition comes with an innovative mindset and a willingness to foster collaboration in different steps of the value chain, to further improve efficiency and sustainability of energy storage systems.