MIT scientists discover a way to use cement to power cars and homes

MIT scientists are proposing cement blocks as a form of renewable energy storage to power houses and wirelessly charge cars.

The solution uses water, cement, and a form of carbon similar to soot which could store enough energy to power entire households.

The scientists say that this type of energy storage “provides a scalable material solution for energy storage to support the urgent transition from fossil fuels to renewable energies.”

Solar, wind, and tidal power collect energy at variable times and often the power they produce does not correlate with peak electricity demand. So, while the energy transition is seeing renewable energy sources surpass fossil fuel-based ones, MIT’s paper writes that finding a scalable energy storage solution is a necessity.

“There is a huge need for big energy storage,” said one professor working on the solution, Franz-Josef Ulm.  “That’s where our technology is promising because cement is ubiquitous.”

As usual batteries rely on materials such as lithium, which are in limited supply and have caused an increased demand for mines, the researchers are banking on the easily accessible, low-cost materials, that can be found “virtually anywhere”, such as cement, water, and carbon.

According to the paper, ‘carbon black’ is an extremely conductive element that can be added to wet cement blocks as they set, flowing through the gaps to create wire-like structures, and turning them into supercapacitors (alongside other processes such as soaking the material in an electrolyte) that are able to hold large electrical charges depending on the size of the concrete blocks.

With this, the researchers predict that the carbon-concrete supercapacitors could be used in the foundation of buildings to provide power, create self-charging roads for electric vehicles, and be able to store energy for wind turbines and tidal power stations.

Currently, the team have already created a set of button-sized supercapacitors which were able to power an LED light, and are now developing a 45-cubic-metre version to show how the technology can grow.

Their calculations suggest a block of this size could store around 10 kilowatt-hours of energy, which is the typical daily electricity usage of a household.

The researchers say that the plan is to commercialise the supercapacitors in the next few years.