Energy storage seems to be standing in the way of any great developments and innovations in the field of renewable energy. This is why, there is an increasing amount of effort that goes towards building devices that can resolve the problem. Here is the latest, an heat-energy storage device that takes limited space and uses paraffin.
Probably the most effective way to store excess energy produced by your solar panels is to use water tanks. Many households opt for them as the water that is heated during the day could either be used as is, or it could serve as a heat storage. However, if you have seen households that have these tanks, you have also probably noticed that they have plenty of space available to place them as the tanks are quite big- a luxury that unfortunately not everyone has.
To deal with this problem, a team of Spanish researchers from Universidad del Pais Vasco and Euskal Herriko Uniberstitatea, developed an alternative to the water tanks energy storage system. It is half the size of a typical tank, it also uses water and it functions just as well. The only difference is that it also contains paraffin.
The unit comprises of two aluminum plates with channels, which seal the paraffin. Once the heated by the solar panels water reaches the device, the liquid starts flowing through the channels between the two plates. The heat from the water is absorbed by the aluminum, warming up the paraffin. As the temperature increases, the paraffin starts to melt and stores the energy from the heat. In order to release the stored energy, the only thing that is needed is to run cold water through the system, which will cause the paraffin to return to its solid state.
The release of energy is relatively fast, the system is much smaller and if this is not enough, it could actually be tailor-made into any desired shape or size. The unit is still a prototype, although the details can already be found in the open access journal Energy Procedia. The inventors are convinced that they can improve it further. They are currently testing various alternatives to paraffin and trying to find one that can store larger amounts of energy.
The guys are also constructing a full-size prototype to demonstrate that the technology really works. They are planning to place it in a governmental office, only that no one is telling which one yet.
Image (C) UPV