Fuel cells – Balance of Plant will be key to success

Author: Andy Potter, Senior Consultant

High levels of growth in the global fuel cell market present opportunities for manufacturers, integrators, and investors alike. Manufacturers and integrators are setting ambitious goals as they look to extend their market presence or make inroads into different industry sectors. Innovation surrounding fuel cell and stack design is a key priority to maximise competitive advantage. Yet these elements represent just one part of the equation. Auxiliary components – or Balance of Plant (BoP) – must also be optimised to ensure new developments are feasible and deliver benefits in target applications.

Fuel cell BoP is a complex matter which should be addressed on a case-by-case basis to deliver the best commercial outcomes. It requires deep industry- and application-specific insight, electrical and mechanical engineering expertise, and a healthy dose of pragmatism.

Weighing up fuel cells’ BoP

In most cases, fuel cells replace an established technology (e.g., batteries in forklift trucks) rather than performing a new function. It’s expected that fuel cell costs will decrease over time leading to more widespread adoption in applications where they can deliver tangible benefits such as reduced carbon emissions. However, overall cost and performance must also be factored into decisions surrounding their use. The wider BoP ecosystem has a significant impact here. Pumps, valves, heat exchangers, sensors, filters, and various other components provide the necessary infrastructure for the fuel cell to function. And they bring a host of additional considerations.

Designers are familiar with these BoP components since they are used extensively across various industry systems and applications. Many are available as off-the-shelf products, however, their cost, functionality, reliability, and maintenance requirements have a cumulative impact on fuel cell value and feasibility. In some cases, BoP components must also satisfy quality and/or safety standards set by the end user or the wider industry.

Each component must be carefully evaluated prior to selection, both in terms of its intrinsic merits and how well it integrates with the system as a whole. Choices and decisions will vary according to performance demands (e.g. response time, weight, duty cycles) which differ between systems. A US Department of Energy fuel cell BoP reliability testbed project  1 acknowledged that “failure or performance degradation of BoP components has been identified as a life-limiting factor in fuel cell systems”. Clearly, the same fuel cell stack may require a very different BoP depending on the use case.

Illustration of a fuel cell ecosystem

How can fuel cell BoP be improved?

Many fuel cell BoP components handle important tasks related to air and fuel management. Low-cost and seemingly trivial items, like air filters, can prove to be an Achilles heel, compromising system performance if they cannot withstand operating conditions. Demands placed on air filters in the BoP for fuel cells used to power a data centre will be quite different to those for a hydrogen fuel cell truck. The latter will likely be exposed to exhaust fumes on the road which risks poisoning the fuel cell cathode catalyst. Similarly, a valve integrated onto a fuel cell stack for an outdoor plant application will have to contend with greater temperature fluctuations, possibly including freeze/thaw cycles, than one used for an indoor application environment. 

To optimise BoP, each component should be specified according to its function and operating parameters. Once a detailed specification is complete, designers can look at how to satisfy the requirements in the most cost-effective way. In many cases, a commodity off-the-shelf product will be sufficient, so attention turns to equipment selection. However, designers may also need to adapt standard components to ensure they integrate and perform as needed. In some cases, it may be necessary to build or commission a bespoke component or sub-module to perform a specific function.

Whether BoP components are procured, adapted, or custom-built, innovation efforts centre on driving down costs without compromising performance. This might involve a review of manufacturing techniques, materials selection, or the way components are integrated. It’s a meticulous process which should be conducted as early as possible in the fuel cell system design cycle. If cost or performance issues arise which require significant changes to the stack or the overall system architecture, it’s quicker, easier, and cheaper to address this before the design is finalised.

The right expertise at the right time

For a fuel cell system to be competitive, its BoP must be as carefully optimised as much as the core fuel cell and stack. To maximise success, digital, electrical, and mechanical BoP components should be assessed by science and engineering specialists who understand the role they play in the system and the demands of the target application. BoP support should be closely aligned with fuel cell system innovation to avoid compromises which may harm the cost and performance profile of the final product. A study of fuel cell installations found that 64% of system failures could be attributed to issues with the BoP.

Sagentia Innovation has the technical expertise and experience to help fuel cell system designers and integrators optimise BoP. From desk-based systems analysis to component identification or the design of bespoke components and architectures, our multi-disciplinary team of scientists and engineers have a strong track record of delivering fluidics systems. Find out how we helped a client develop and manufacture a hydrogen generation cartridge for a portable fuel cell system here.

In this highly competitive, fast-growth market, our support will help you get ahead. Contact us to find out more /contact-us/

 

1 Reference: Fuel Cell Balance-of-Plant Reliability Testbed Project (Technical Report) | OSTI.GOV https://www.osti.gov/biblio/1335164  

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