Energy-efficient fuel cell technology
Fuel cell systems are an efficient way of converting chemical energy into electricity so as to reduce emissions and protect the environment. EU-funded research has advanced existing components and designs to develop an optimised version - boosting product lifetime and efficiency, and potential commercial uptake of a sustainable energy solution.
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Reducing greenhouse gas emissions is vital for our planets future. Fuel cell technology has considerable potential in this area. Compared with other options, it reduces emissions even when powered by fossil fuels. When green hydrogen is used, emissions are close to zero. However, there is always room to improve its functioning.
The EU and industry-funded DEMSTACK project, supported by the Fuel Cells and Hydrogen Joint undertaking (FCH JU), has developed a prototype 1 kilowatt fuel cell system. One potential use for the system is for combined heat and power generation. By increasing the efficiency of the process, the system reduces the amount of primary energy needed, bringing environmental and economic benefits.
Other applications include auxiliary power units on vehicles, standby generators for use during power outages, liquefied petroleum gas battery chargers, power supply in remote areas and satellite technology.
The prototype achieved electrical efficiency above our 38 % target. It reduced critical raw material (in this case platinum) usage by 40 % and showed no signs of degradation during operation, so the system lifetime is extended, says project coordinator Maria Daletou of the Foundation for Research and Technology, ICEHT/FORTH in Greece.
DEMSTACK further advanced and integrated promising electrode and membrane materials into an improved fuel cell assembly or stack design. A fuel processor which produces hydrogen to convert fuel into electricity operating on natural or liquefied petroleum gas was built and combined with the stack. The prototype was tested under variable conditions to improve the components and mitigate system failures.
Improvements to the membrane electrode assembly the core component of a fuel cell where the electrochemical reactions take place have reduced degradation rates and increased resistance to contaminants such as carbon monoxide.
The system can thus be powered with lower quality hydrogen and the fuel processor can be reduced in size. As a result, the setup is simplified, and the system is more efficient and less voluminous.
The fact that the fuel cell operates at high temperatures up to 200 ºC has additional advantages. For example, it can be cooled in such a way as to generate high-grade waste heat that can then be recovered and used. High-temperature fuel cell systems also operate more flexibly under dynamic conditions and require fewer peripheral components, thus reducing auxiliary energy consumption and increasing efficiency.
Knowledge exchange within DEMSTACK has raised levels of expertise among the SMEs involved, giving them the chance to broaden cooperation with industrial end users. They have a reliable prototype to show potential buyers and partners, and are capitalising on the results to improve existing products.
One firm plans to use the technology to develop auxiliary power units, while some of the partners have signed contracts with the European Space Agency to make systems for space applications based on the prototype. Furthermore, nine scientific articles have been published and 38 papers on the outcomes have been presented at various events.
The systems robustness, simplicity, stability and user-friendliness have been demonstrated and this is expected to help market penetration. Being able to demonstrate the prototypes efficiency, the companies can continue their cooperation by pursuing funding for testing or identifying end-users, concludes Daletou.
Further development is necessary to complete the transition from small- to large-scale and determine optimal operational conditions and system stability. Successful implementation in existing and future infrastructure will open up new perspectives for fuel cell technology and offer substantial scientific, economic, energy and environmental benefits, she adds.