Gerhard Swart, Advisory Member and former Key Programme Manager at Hydrogen South Africa (HySA) spoke at COE September Focus Group on Sustainable Power Generation and Energy Storage Solutions. Gerhard presented on ‘Design, applications and the future of the Hydrogen Fuel Cell’. In this interview Gerhard dives into the core themes of his presentation. The challenges with, considerations for and applications of Hydrogen Fuel Cells. 

Yes and no. As the top producer of Platinum in the world, South Africa certainly has a potential advantage in the manufacturing of Fuel Cell (FC) components and systems. If HySA (Hydrogen South Africa) is successful in helping establish more of the FC value chain, and move away from purely exporting Platinum, several new industrial end economic opportunities will arise. The home-grown catalyst, MEA and system technologies are also very promising, and if nurtured could support these new opportunities.

The difficulty I believe is twofold:

Firstly, the level of industrial investment required to unlock this opportunity is beyond what government is generally spending in this area today and there are many competing and urgent needs for government funding.

Secondly, there are powerful global competitors that are seeking not only alternatives to Platinum but also developing their own technologies. Some governments are investing a hundred times as much as the SA government to ensure that their industries benefit from the potential Hydrogen Fuel Cell market. SA’s institutions and businesses should consider entering strategic partnerships with these foreign companies to maximise the long-term benefit for SA.

Fuel Cells (FC) have electrical and mechanical limitations that require careful consideration during their application, else their reliability, safety and useful life are compromised.

Some of the specific considerations for Hydrogen Fuel Cells are:

A) Fuel Cells take a finite time to ramp-up when high power output is required by their load. This means they are best used at a reasonably constant power. Many real-life applications such a Fuel Cell Vehicles and domestic power provision (CHP) have quickly varying loads, so generally a battery system is required alongside the FC. An electronic controller is then also needed to manage the battery charging and FC operation.

B) Fuels Cells require very pure Hydrogen and clean air, otherwise they degrade and can fail completely. This means that the air intake of a FC requires high grade air filters that remove pollutants and regular replacement of those filters. The pure Hydrogen is also more expensive and difficult to manufacture, but progress has been made in standardising what is required through the development of ISO14687.

C) Fuel Cells generate a large amount of heat due to their ~50% efficiency. Overheating can cause permanent damage, so they sometimes require elaborate cooling systems.

D) Hydrogen gas is very dangerous and explodes or burns easily in air. As an odourless gas it is not always detected, spreads very easily and quickly, and can be ignited by sparks or static electricity. Ensuring that FCs, and their Hydrogen piping and storage vessels never leak, even after many years of use, presents many challenges.    

I believe that the three greatest challenges to be overcome are cost-effectiveness (which relates to efficiency), re-fuelling infrastructure, and safety.

1) Using Fuel Cells on cars adds a great deal of complexity, which increases the vehicle cost. The user experience must also not be unduly compromised, by for example cramping the occupants to make space for Hydrogen storage tanks.

The FCs are also only around 50% efficient, and though this is better than Petrol and Diesel engines, it does not match the +95% of competing battery technologies – the achievable range using batteries has become acceptable and cost competitive. Ultimately, the consumers will be strongly influenced by the vehicle price and the cost of “fuel”, which must be addressed.

2) Car owners also need easy access to affordable Hydrogen. Presently Hydrogen is much more expensive (per km travelled) than Petrol or Diesel, and there are only a handful of re-fuelling stations. The refuelling stations are complex and very expensive compared to EV charging stations, so governments, businesses and consumers are hesitating as they wait for clear indications that this is the best automotive technology to back.

3) Automotive companies have made major strides in addressing the safety of FC cars, but this remains inherently difficult. Although static installations using Hydrogen can be fenced off with no-smoking signs and protected by anti-static measures, this is not practical in a moving vehicle in the hands of a consumer.

At present Hydrogen Fuel Cells are probably best used in static or large mobile installations, where battery technology is impractical or more expensive.

Some such applications may be:

• Combined Heat and Power in locations that have natural gas, particularly where this has been enriched by Green Hydrogen.
• Large mobile applications that require a large amount of on-board energy storage, but where space is not at a premium (e.g. ships). These environments can almost be considered “static” making it easier to overcome the technology and safety challenges.

There are also niche applications where air quality or other operational constraints make the technology attractive.

These include:

• Underground mining vehicles. Their large size allows adequate on-board Hydrogen storage and emissions are not harmful in the underground environments. Longer operating times may be achieved than with battery technology alone.
• Forklifts in food warehouses. CNG or Diesel forklifts are not allowed, and electric forklifts may have less operating time than FC-powered ones.
• Long-duration Uninterruptible Power Supplies (UPS). Battery UPS backup times are determined by their battery size, which typically would be 20min to 2h. Longer backup, where required (e.g. mobile phone towers) is typically provided by Diesel generators, which emit CO₂ and pose a refuelling logistic problem to operators. An electrolyser-HFC combination with a large Hydrogen storage tank would provide a long-duration UPS that never requires re-fuelling.