Previously technologies that capture the heat that is given off by electronics, engines, and buildings, such as factories, and then turn that heat into electricity have been studied. But researchers at the University of Minnesota in the College of Science and Engineering have recently developed a multiferroic alloy metal material that converts heat directly to electricity.
The multiferroic alloy is composed up of Cobalt, Nickel, Manganese and Tin that was combined at the atomic level and is entitled Ni45Co5Mn40Sn10.
“Multiferroic materials are known for having unique elastic, magnetic and electric properties, and in the case of this alloy, that takes a form of an usual phase change. When heated, the non-magnetic solid material suddenly becomes a strongly magnetic solid.”
It is nonmagnetic material that when a small amount of heat is applied it becomes magnetic and the magnetic material produces electricity.
During this step some energy is lost in a process known as hysteresis but the researchers at the University of Minnesota have minimized that loss making the alloy material a very successful conductor of electricity.
“This research is very promising because it presents an entirely new method for energy conversion that’s never been done before,” said aerospace engineering and mechanics professor Richard James, who led the research team. “It’s also the ultimate ‘green’ way to create electricity because it uses waste heat to create electricity with no carbon dioxide.”
The alloy is in the very early stages of development but it may become an alternative or replacement for the current use of thermocouples.
Thermocouples are two different conductors, usually metal alloys that produce a voltage proportional to the temperature difference at each end. They have been used to convert heat into electricity in items such as water heaters, etc.
This new multiferroic alloy allows for the production of electricity in broader and smaller temperature variations.
It could be used to capture the heat from car exhaust and power the battery of a hybrid or heat from factories and used as their form of electricity.
Once Ni45Co5Mn40Sn10 is tested and if production can be achieved at large levels with a small cost range there is no limit to what this new alloy could be used for.
It is incredible to think that every machine, electronic or building that we use could be on a cycle. They all produce heat that today is released as waste, but that heat would be captured through the metal it flows through and turned back into electricity to power the very product that produced it.
This is the very essence of cradle to cradle products, where no waste is produced, and a material has a never ending lifecycle.