Today, I go on about Jeremy Rifkin’s Third Industrial Revolution with its third pillar, which is about storing electricity.
What’s at stake?
Ever since we produce and consume electricity, the need for storage has been existing. Because our consumption is fluctuating, because transporting energy (to another consumer further away) brings about energy losses, because our energy grids don’t like ups and downs. In a nutshell, given the physical caracteristics of electricity and our electrical grids, it would be best to consume energy when and where it is produced… which is of course not always possible.
So if it isn’t that new, why does Jeremy Rifkin say that storing electricity is the TIR’s third pillar? First because renewables energies (the TIR’s first pillar) are mostly intermittent, which means the production isn’t steady. Second because renewables are distributed: isolated homes and businesses gain access to renewable energies and as they too are able to produce electricity, they need to store it.
What’s so difficult?
Of course, if we’re talking about it, it means it’s not so easy, but why? First because, just as energy transportation brings about losses, storage causes waste. The actions of storing first and then releasing energy are costing energy. The efficiency of a storage solution can never be 100%, there’s always less energy released than was stored.
Second because electricity is a secondary form of energy (one which is obtained after transformation of a primary source of energy) and therefore isn’t directly storable: you have to transfer electricity in something else to store it and release it later on.
So how do we do that at all?
Today, the most used storage solutions are simply put those with best efficiency at a reasonnable price, that is mainly :
- Hydropower dams (about 80% efficiency)
- Energy transfert pumping station (about 80% efficiency)
- Electro-chemical batteries (70-80% efficiency)
On the research side, we’re currently all on hydrogen and fuel cells, compressed air, flywheels, and supercondensators. These technologies are either more efficient (and more expensive), either more simple or abundant (and less efficient). I won’t go into details about how they work and what their advantages are because you’ll find here under a table in which I have listed the main types of energy storage, their working principle and a few examples of their applications.
Recap and explanation of the main storage options to date
Main source (in French): http://www.connaissancedesenergies.org/fiche-pedagogique/stockage-de-l-energie