Up until now, we have been familiar with solar panels to sustainably power our houses, but what if a home is powered from its materials? Yes, MIT researchers discovered that supercapacitors have the potential to power a house. Professor Franz-Josef Ulm, leading the project, aims to develop sustainable and accessible energy solutions. The project focuses on using widely available materials such as concrete and charcoal.
In the near future, houses might be equipped with innovative concrete columns blended with charcoal, enabling them to conveniently store electricity and release it when necessary for the residents’ use. MIT researchers have created a supercapacitor that functions like a battery but does not degrade with use. It is made from common materials and aims to save renewable energy inexpensively and effectively.
The designers of concrete supercapacitors are already envisioning even more remarkable applications for this technology. Examples include charging electric vehicles while they are in motion and ensuring uninterrupted power supply during severe weather events.
Project leader and professor of engineering at MIT, Franz-Josef Ulm, said, “These are sort of the frontiers where we are working right now with this technology, now we have shown how it scales. These two materials here come together to form potentially an energy storage solution for everyone, everywhere.”
A supercapacitor, contrary to a battery, stores electrical energy directly in a conductive material, like electrolytes or salt water, on an electrode’s surface.
This conductive material is separated from an insulating one, preventing the free flow of electrons, just like in a circuit. As a result, an accumulation occurs – similar to the static electricity that builds up when you rub a balloon.
Prof. Ulm explains, “Here, the wonders of chemistry take place. When you mix cement—which loves water, it’s hydrophilic—with carbon black [refined charcoal], which hates water, then the carbon black first clumps and then the same water is consumed within the hydration reaction” that forms solid concrete.”
“As a consequence of this consumption, these clumps loosen and build up a volumetric wire throughout the material. That volumetric wire is everywhere, and as a consequence we can store [an] enormous amount of countercharges from the salt solution onto this volumetric wire,” Professor Ulm further added.
Pros of Concrete
Naturally, concrete is porous and has pores through which it easily absorbs salt water. According to Prof. Ulm, it can easily do so via the carbon wire running through it. Between the electrodes in the form of disc it looks like Oreos, that can be attached to each other easily in the form of a stack.
Concrete and charcoal are widely accessible materials that can be found all over the world. Particularly, concrete is incredibly popular and consumed on a massive scale, ranking second only to water. The versatility of concrete is enhanced by its powdered form, which enables the customization of supercapacitor designs to suit various applications, as highlighted by Prof. Ulm.
Prof. Ulm mentioned, while an average lithium battery can only be charged and discharged 300 to 500 times, a supercapacitor can be charged and discharged countless times without any loss in efficiency. This is because supercapacitors do not need to convert energy from one form to another.
“If everybody had one of these supercapacitors in their foundations [or] in their wall systems, and they were connected to the [energy] system, we would be talking about a real smart grid, in the sense that it involves everybody. Everybody is contributing with their building to achieving the energy transition,” Prof. Ulm said.
Other Potential Applications
After discovering supercapacitors have the potential to power a house, Ulm and his team have grand aspirations for their concrete supercapacitors that extend far beyond merely storing domestic energy. As the number of individuals embracing electric vehicles continues to soar, concerns about charging infrastructure and limited mileage between charges have become increasingly prominent.
As Professor Ulm describes the benefits of supercapacitors, MIT researchers are focusing on developing a self-charging road that aims to charge an electric vehicle using electromagnetic induction, either while parked or while driving, just like charging an iPhone without a cable.