Daily Management Review

Concentrated Solar Plant System To Dispatch Electricity To The Grid On Demand


The researchers at MIT have proposed a new system which leaves the lithium battery storage system behind.

The scientists at MIT have come up with a system designed to “store renewable energy” like wind and solar energy for supplying it back to the electric grid when required. The “Energy and Environmental Science” journal informed that the system has been created to “power a small city” all around the day irrespective of the weather conditions.
The excess heat energy generated from wind or solar powers are stored in “large tanks of white-hot molten silicon” in the new storing system following which the light is converted from “the glowing metal back into electricity” when required. According to the experts at MIT, this kind of system will be “more affordable” in comparison to “lithium-ion batteries” which are viable yet expensive way of storing renewable energy.
In the words of MIT’s associate professor, Asegun Henry:
“Even if we wanted to run the grid on renewables right now we couldn’t, because you’d need fossil-fuelled turbines to make up for the fact that the renewable supply cannot be dispatched on demand. We are developing a new technology that, if successful, would solve this most important and critical problem in energy and climate change, namely, the storage problem”.
While designing the new system the researchers attempted to “increase the efficiency of a form of renewable energy known as concentrated solar power”. In conventional systems of solar plants, solar plants directly convert light into electricity while in the concentrated system, huge mirrors spread across vast fields “concentrate sunlight onto a central tower” wherein it gets converted into heat and eventually is “turned into electricity”.
While, Henry added:
“The reason that technology is interesting is, once you do this process of focusing the light to get heat, you can store heat much more cheaply than you can store electricity”.
This system collects solar heat in a “large tanks filled with molten salt” which gets “heated to high temperatures of about 538 degrees Celsius”. During the conversion process to electricity the hot salt gets “pumped through a heat exchanger” transferring the heat of the salt into steam then a turbine is used to turn “steam into electricity”. The “Thermal Energy Grid Storage-Multi-Junction Photovoltaics”, in short “TEGS-MPV”, is the name given to the “new renewable energy storage system” as the researches outline their concept for the same.
However, the research have also proposed an alternative for “fields of mirrors and a central tower”, whereby to convert the electricity sourced renewably into thermal energy. In order to materialise the same one would need a system with “a large, heavily insulated, 10-metre-wide tank made from graphite and filled with liquid silicon, kept at a ‘cold’ temperature of almost 1927 degrees Celsius”. In addition to it, one would also need “bank of tubes” that would connect the cold and hot tanks and as the solar cells supply electricity into the system, the will get “converted to heat in the heating elements”.