The drive towards hydrogen

In the last edition of SPAL Shaping Air, we talked about the expected rise and use of hydrogen and electric vehicles, which are both environmentally friendly alternatives to traditional gasoline and diesel vehicles. However, in this article, our general manager, James Bowett , takes it one step further and delves deeper into the significant role hydrogen will play in the future of transportation and the technological innovations that will drive this change, such as thermal management.

The debate between hydrogen fuel cell vehicles (FCEVs) and battery electric vehicles (BEVs) often creates a divide, with supporters advocating strongly for one over the other. However, this doesn't have to be the case as explained in my last piece, with leading vehicle manufacturers now investing in both technologies, recognising that no single solution fits all scenarios.

Industry analysis by IDTechEx suggests that despite BEVs being likely dominate the zero-emissions vehicle market in the long run, FCEVs are projected to experience significant growth. For clarity, IDTechEx provides independent research on emerging technologies and their markets.

With the expansion of hydrogen infrastructure, support from key automotive manufacturers is pushing efforts towards a hydrogen economy. As a result, IDTechEx also forecasts a 60-fold increase in the number of FCEVs over the next two decades, spanning across cars, trucks, vans and buses — all of which SPAL works with.

The technological advancements

According to the US department of energy, fuel cell systems in hydrogen-powered vehicles can use 60 per cent of the fuel's energy, resulting in a reduction of over 50 per cent in fuel consumption.

What’s more, fuel cell systems can generate electricity at efficiencies up to 60 per cent and even higher with cogeneration. These statistics are both comparative to a conventional vehicle with a gasoline internal combustion engine.

This is due to the current innovation in technology, such as fuel cell efficiency, which is improving through the development of better catalysts and membrane technologies. Catalysts, such as platinum alloy catalysts, enhance the rate of hydrogen oxidation and oxygen reduction reactions, which are critical for fuel cell performance.

Meanwhile, proton exchange membranes (PEMs) are seeing advancements that increase conductivity and stability, reducing energy losses and improving overall system efficiency. Such innovations in materials, like non-precious metal catalysts and durable membrane materials, also help lower manufacturing costs — another focus area.

Storage solutions

For hydrogen storage, high-pressure tanks made from high-strength composite materials allow for safe storage at pressures up to 700 bar. These tanks are lighter and more compact, enhancing vehicle design and efficiency.

For example, cryogenic storage technology enables the use of liquid hydrogen, which has a higher energy density than compressed gas. This involves storing hydrogen in its liquid form at extremely low temperatures, typically below -253°C (-423°F), which allows for a higher energy density compared to compressed gas storage.

Such method of storage is particularly useful for applications requiring large amounts of hydrogen in a compact form, such as in certain heavy-duty vehicles and aerospace applications.

Research into solid-state storage is also promising. Metal hydrides and chemical hydrides can absorb and release hydrogen at relatively low pressures and temperatures, improving safety and energy density. These innovations offer potential for safer and more compact hydrogen storage solutions.

Thermal management

Effective thermal management is crucial for the performance and longevity of HFCVs and the technological advancements detailed above. Innovations in this area focus on maintaining optimal operating temperatures for fuel cells, managing the heat generated during hydrogen compression and storage and ensuring efficient cooling of vehicle components.

Advanced cooling techniques, such as liquid cooling systems, circulate coolant through channels in the fuel cell stack to absorb and dissipate heat. The development of coolants with higher thermal conductivity enhances heat transfer efficiency.

Phase-change materials (PCMs) are also being integrated into thermal management systems. These materials can absorb and release large amounts of heat during phase transitions, providing efficient temperature regulation for fuel cell components.

However, enhanced airflow management is the major area of innovation in this context. High-performance fans and blowers, such as those developed by SPAL, increase airflow over the fuel cell stack and other critical components, improving heat dissipation.

These fans are also used during hydrogen refuelling to manage the heat generated during compression. Innovations in vehicle design to optimise airflow around key components can further enhance cooling efficiency and reduce the need for additional thermal management hardware, saving on cost.

Case examples

For commercial use, heavy-duty hydrogen internal combustion engine (ICE) trucks were once considered a pipe dream for businesses and climate activists. However, industries from transportation and shipping to waste collection and construction are now moving towards a sustainable future, with hydrogen playing a key role.

Heavy-duty hydrogen ICE trucks are heavy-duty vehicles equipped with engines that burn cleaner and more efficient hydrogen. The definition extends to any vehicle with a gross vehicle weight (GVW) of more than 26,001 pounds equipped with an ICE that burns hydrogen gas and does not require any fossil fuels to operate. This weight class includes long-haul semi-trucks, cement mixers, garbage trucks, mobile cranes, transit buses and so on.

For example, companies like Cummins, a global leader in power solutions, and Westport Fuel Systems, a key player in alternative fuel,?have unveiled heavy-duty truck engines that run on hydrogen gas.

As these proof-of-concept technologies hit the roads, its these types of innovations that are helping to drive the charge towards hydrogen. If you’d like to find out more information about how our fans can optimise thermal management for your operations, please visit https://www.spalautomotive.co.uk.