With the increase in the production of energy from green resources, it becomes essential to look at methods and techniques to store this energy. But for supplying, we first need to have a depot, a deposit with the correct criteria and adaptable to our needs. Therefore scientists and engineers have been working on diverse solutions and alternatives to this problem. 

The main Energy storage techniques are classified into different categories. The first one is Superconducting Magnetic Energy Storage, an advanced method in which a superconductor coil is cooled below its critical temperature provoking negligible resistance, hence, the superconductor will continue flowing thanks to the creation of a magnetic field. 

Also, there are systems like batteries and fuel cells. Electrochemical systems are setups of two or more electrodes spatially separated and distributed throughout one or more ionically-conductive media. Electrochemicals have their advantages because of their simplicity, low cost and speed. 

However, batteries cannot withstand high cycling rates, nor store large amounts of energy in a small volume. That is why other types of storage technologies are being implemented.

Technologies such as hydro systems are an option that works by converting the pressure into rotary mechanical power and then using a generator to turn the mechanical strength into electricity.

In Mechanical systems, the energy is stored by applying force to an appropriate medium to deliver acceleration, compression, or displacement. 

As all the methods mentioned earlier, the processes can be reversed and the stored potential can turn into energy or electricity.

 There are various types of storage methods, some of which are already in use, while others are still in development. 

According to The Union of Concerned Scientists, Energy storage can reduce high demand, and waste, but community resiliency and government inversion are the fundamentals.

Energy storage can help meet peak energy demands in densely populated cities, reducing pressure on the grid and minimizing pinpoints in electricity costs.

We have alternatives and the storage may be a challenge but it is fundamental to start working so we can find ways to store energy and transform it back when needed.

Among all this options, my favorite one is the Mechanical Energy Storage System because it takes advantage of kinetic and gravitational forces. But, how does it work? 

The flywheel energy system works by accelerating a rotor to a very high speed and converting power into kinetic energy. The thesis behind this technology is that the surplus electricity that is stored drives an engine which spins a flywheel thousands of revolutions per minute.

The flywheel system is not new, it is used in countries such as Switzerland and the Netherlands. 

The flywheel moves because it levitates in a vacuum chamber with high-efficiency magnets and bearings. 

But why is mechanical energy storage an alternative?

Contrary to other ESS systems. The flywheel neither contributes to greenhouse emissions nor has an accelerated degradation process. Why is degradation so important?

Unlike batteries, the flywheel system is not vulnerable and has a long usage life. 

If an ESS system has a rapid degradation process, it will not be reliable and may be defenceless to repeated cycles. 

As expected, the flywheel system has issues, such as materials and manufacture costs, short discharge times and relatively high parasitic and intrinsic losses. (Source: EPRI, 2002)

But in any ESS system, we face challenges that can be shadowed by advantages such as carbon neutrality.

Flywheel storage systems can charge and discharge at increased rates for countless cycles without degradation throughout their 20-year life. They are also used with UPS and no batteries; in other words, they reduce the carbon footprint and recycle energy by converting it into electricity or heat.

Even though there are numerous energy storage systems. The most used around the production world is batteries, which as I mentioned earlier, are vulnerable; lithium-ion batteries became famous because of zero maintenance, fast charge and long run time. But the shininess and newness of technology don’t mean it’s without its downfalls. Only 5% of Lithium Ion Batteries are recycled and even if they do not require maintenance, lithium still needs periodic inspection of cables, terminals, etc.

With batteries, it is crucial to return lead-acid batteries. Improperly thrown-out batteries can even short-circuit, overheat, cause fire or end up in a landfill where pollutants can leak out and contaminate groundwater, damage fragile ecosystems, and potentially make their way into the food chain.

That is why we should consider flywheel a possibility because it is not about materials, it is about strategy.

Conclusion: 

Flywheel energy storage (FES) is one of the most competent ESS. Compared with batteries, this storage system can operate under a wider range of temperatures and has no toxic consequences on the atmosphere.