System Integration

Liquid Hydrogen Storage involves material contraction and expansion considerations at the design stage. Hence, fabrication and welding are an essential cross-sector skill that can be transferable to the sector, along with the design, control, and regulations surrounding pressure equipment manufacturing. The lack of standardisation and commercialisation of liquid hydrogen tanks means that the company currently does not commit to high volume manufacturing, and there are no products available off-the-shelf. Hence, each product is custom built, and the legalities, standards, and safety measures are decided upon taking into consideration the specifications requested by the client, following the directives detailed in the previous section. However, the lack of client experience with liquid hydrogen storage presents with significant challenges, and constantly varying client specifications result in project delivery delays. In terms of whole systems integration of liquid hydrogen tanks, the company reported not being involved with any upstream applications (such as liquefiers) or downstream applications (such as fuel cells and vaporisers) but do support customers with super vacuum insulated piping requirements. For large scale applications storage applications, liquid hydrogen pumps are a necessity, yet the company is unaware of any pump manufacturers in the UK. The system integration of liquid hydrogen storage tanks is a complex endeavour, and the most critical component is cryogenic temperature rated valves. However, since the UK does not manufacture such valves, the company is forced to source these components from Germany, Switzerland, and the USA, presenting a supply chain risk, especially considering tariffs

Proton Exchange Membrane Fuel Cell (PEMFC) systems primarily have applications within the automotive and aerospace industry. Hence, systems engineering, control expertise, and experience of safety and certification in these industries is transferable to the PEMFC industry. Usually, for heavy duty automotive applications, stationary and portable power applications, and UAV applications, PEMFC systems are commissioned off-the-shelf, while passenger cars and aerospace applications require case specific modifications. Where products require significant variations, the company work with the client to define requirements and specifications but face significant issues in the supply of green hydrogen. Hence, the company is trialling some products with an integrated electrolyser to combat issues surrounding hydrogen supply. In terms of whole system integration for PEMFCs, it is imperative that a regulated and uninterrupted supply of hydrogen be available, especially for large-scale applications. Since the PEMFC only provides an unregulated DC power output, a DC/DC converter and an inverter is required for power management. Large scale PEMFC systems produce a significant amount of waste heat, and clients have expressed interest in utilising the waste heat for CHP applications. The company reported that they can assist with waste heat reutilisation but require commercial pull from the market for implementation. Currently, the company utilises the wastewater from the PEMFC system as a cooling mechanism through their proprietary cooling design for high power applications, whereas the wastewater is released to the environment (as steam) for low power applications.

Solid Oxide Fuel Cell (SOFC) and Solid Oxide Electrolyser Cell (SOEC) systems combine different science disciplines, and cross-sector skills from chemistry, materials science, engineering, and manufacturing are transferable. Since the company licenses their core proprietary technology to manufacturers, they are generally not involved with end-use clients. However, they reported having a high steam utilisation for increased system efficiency and have observed traction for CHP applications for MW scale solid oxide products. Since the SOFC and SOEC systems already have a higher efficiency than PEMFC systems, integration with waste heat for cogeneration applications can increase the balance of plant efficiency to 95 %. Several end-users of solid oxide technology have demonstrated this integration at the MW scale, such as Shell and Sunfyre, especially within the steel industry. One of the major integration challenges for the solid oxide technology is the availability and cost of high-quality hydrogen compressors and forms the biggest supply chain risk. Apart from the supply chain, the company faces major technological challenges in terms of lower costs and increasing lifetime of the solid oxide technology. Additionally, the cost and availability of green hydrogen for SOFCs and cost of renewable electricity for SOEC presents a significant challenge towards commercialisation. The Asian markets present as the ideal end-user for rapid commercialisation, due to the availability of low-cost renewable electricity. Still, silica poisoning, degradation, and system assembly issues are continuously being addressed to increase viability of the solid oxide technology. The company recommends the government to increase funding for the research and development of low-cost and reliable compressors and the availability of low-cost green hydrogen, hence generating market pull for solid oxide technology.