According tomedia reports, many industries use thermally intensive processes that typically require the burning of fossil fuels, but a surprising green alternative is emerging in the form of metal powders. This very finely ground, inexpensive iron powder burns easily at high temperatures, releasing energy during oxidation, a process that does not emit carbon that produces only easily collected rust or iron oxides — yes, that’s its only emission.
If burning metal powder as fuel sounds strange, the next part of the process will surprise you even more. During combustion, iron is used as a cleaning battery, charged in a variety of ways, including electrolyte, and discharged in flame and heat.
Recently, Germany’s Swinkels family brewer became the first company in the world to industrialize the process. The company has been working with researchers at Metal Power Consortium and Einhoven University of Technology to install a circular ferro-fuel system at its Bavarian brewery that provides all the calories needed for about 15 million beers a year.
As a combustion clean energy storage medium, the advantages of iron powder include its low cost and abundant grain reserves, easy transport and good energy density, high combustion temperature of up to 1800 degrees C, and the need for low temperature cooling or long-term storage or loss of any energy.
The system’s round-trip energy cycle efficiency depends on the process of injecting energy into the iron during regeneration. According to the paper, highly efficient electrolyzed iron oxides can store 80% of the input energy in iron fuel, a figure similar to modern hydrogen cracking methods.
But the technology clearly has bigger plans than just starting individual industrial applications — not just those that mainly output heat. “While we are proud of this huge milestone, we also look to the future,” said Chan Botter, head of SOLID, a student team at Einhoven Technical University dedicated to metal fuel development. We also plan to build a 10-megawatt power generation system by 2024. Our goal is to convert the first coal-fired power plants into sustainable iron-fueled power plants by 2030. “
According to the paper, the theoretical efficiency of using this cycle process to generate electricity can reach about 40%.
Of course, economics will ultimately determine how far this idea can go, which remains in doubt at this early stage, but it clearly has some advantages over hydrogen, pumped storage, batteries or momentum storage.