Will a cost-effective, power-storing cement mean our buildings can act as batteries?
What if a building could act as a battery? I am not talking about a wall-mounted battery, but energy that is stored within the fabric of the building.
It sounds like a futuristic concept, but researchers at Lancaster University have managed to develop a cement mixture that can store electrical energy. Not only that, but buildings made from this smart substance will be able to monitor their own structural health.
The cement mixture created by researchers is made from fly ash and chemical solutions, and the resulting potassium-geopolymetric (KGP) composites are more economical than ordinary Portland cement.
Potassium ions hop through the crystalline structure, making the substance conductive, and no expensive additives are needed. This is a step forward, as other smart concretes have relied on additional elements such as graphene and carbon nano-tubes. It makes them too expensive and also difficult to use on a large scale.
The new KGP composites have the ability to store electrical energy and also to detect mechanical stresses. Potentially, structures made from this material could store and discharge between 200 and 500 watts per square metre.
How this would work in practice is that anything built from this material would need to be connected to a power source. An ideal eco-friendly source of power would be solar panels.
Aside from the obvious uses in homes and commercial buildings, practical applications include:
- Electric vehicle charging points
- Traffic lights and street lights that can function off-grid, and
- Kerb stones that power sensors to monitor traffic flow, drainage and air quality.
It is important to note that this cement does not need to be limited to new buildings, as KGP panels could be retrofitted to existing buildings.
From providing power in homes, to electric car-charging points, if this cement makes it from the research phase to production, it has the potential to transform the way we power our lives.
On top of the power-related benefits, the KGP cement mixtures will be able to sense structural changes. If a crack forms, this will disrupt the way ions hop through the structure and therefore affect conductivity.
These changes mean the structural health of buildings can be monitored automatically, by measuring conductivity, without the need for additional sensors.
Instead of relying on routine visual checks, using this cement at critical stress points would send immediate alerts when structural defects such as cracks occur.
This would be a positive development for the monitoring of buildings, bridges and other structures. If this cement begins to be used in construction it will be an interesting development, so I will be keeping an eye on this area of research.
And if you have a project that needs the input of a structural engineer, please do get in touch.