Energy storage: a key element of the energy transition

Energy storage: a key element of the energy transition


What is energy storage? 

The increasingly widespread adoption and efficient use of renewable sources requires that energy passes through energy storage systems in which the generated electricity is first stored and then later distributed at the right moment. Because of this, storage systems are crucial in balancing energy supply and demand and keeping the distribution grid stable and efficient.


How is electricity stored? 

To date, the most popular and widely used energy storage systems are batteries, which have undergone an exponential technological evolution over time aimed at providing greater efficiency at a lower cost from a production point of view as well. This is thanks to an approach that aims to achieve an increasingly advantageous relationship between environmental sustainability and economic viability, in line with circular economy principles.

The battery storage systems in renewable plants closely resemble the smaller batteries commonly used in homes on a daily basis. Both types can store energy through a chemical reaction and subsequently convert it into electricity as needed.

In particular, the batteries connected to a plant receive the energy generated from a renewable source, for example from solar panels, which is then stored as electricity and released when necessary to meet consumption needs. The charging and discharging cycles are managed and monitored in real time using special software that, through the constant analysis of demand and supply, guarantees the maximum efficiency of the energy storage system.


Storage technologies in step with innovation

As renewable sources (e.g. solar and wind) are by their nature subject to fluctuations in availability, due to intermittent weather conditions, it is imperative to develop energy storage systems capable of storing the amount of energy needed to handle peak moments of demand, supporting the increasingly systematic use of green electricity.

The progress made in the field of renewable energy generation has been accompanied by a parallel evolution of the technology behind Battery Energy Storage Systems (BESS). At present, the most widespread technology is based on the use of lithium batteries, as it is a material that offers significant advantages in terms of efficiency and durability. But in the near future technological innovation will allow for the adoption of new storage devices capable of storing higher amounts of energy, such as flow batteries with alternative chemical flows made using elements such as vanadium, iron and zinc.

Lithium batteries are also on a path of natural technological evolution. In fact, they will soon shift away from standard models towards new devices with a solid-state electrolyte.


The many applications of energy storage 

Energy storage systems have multiple fields of application: in addition to providing power for electrical equipment and device consumption, they are essential for facilitating the spread of sustainable mobility and play a primary role in supporting not only the power grid, but also stand-alone systems called microgrids.

A microgrid is a local energy production and distribution network that can function independently when it is disconnected from the main electricity grid in the event of a crisis, such as a blackout or a storm, or simply to supplement peaks in demand from its users, thereby avoiding higher energy costs.

Above all, energy storage systems are essential for storing and distributing electricity produced from renewable sources, supplying the national grid with clean, locally produced energy at a more advantageous price.


Storing renewable energy

The availability of renewable energy sources around us is not always constant or predictable. This is why energy storage systems are fundamental for stockpiling the electricity produced by plants when there is an abundance of renewable energy, so that electricity can be stored when it is most economically advantageous to produce it and then used at the most opportune time, creating a balance between supply and demand.

One especially important element has to do with increasing the efficiency and resiliency of renewable energy plants – which, by their very nature, are dependent on variable factors like weather conditions that can determine, for example, the intensity of solar radiation and the resulting energy generated by photovoltaic panels.

In this industry, there is a great focus on environmental sustainability: systems for second-life storage are now able to be adapted to large-scale facilities, as evidenced by the PIONEER (airPort sustaInability secONd lifE battEry stoRage) project at Rome’s Leonardo da Vinci - Fiumicino airport. Thanks to batteries supplied by three different car manufacturers, the surplus energy produced by the solar system placed alongside one of the runways can be stored and then used to take on peak demand at Italy's largest airport.   

Storage systems are demonstrating innovation in all industries, including geothermal energy, such as at the Santa Barbara plant in Cavriglia, which uses a particularly cutting-edge, sustainable system for storing thermal energy. Thermal Energy Storage (TES) is an absolutely one-of-a-kind system in the world in that it allows for storing and utilizing thermal energy on an industrial scale via a material that is readily available: rock. During the charge phase, the heat generated by the plant runs through tubes placed in fragmented rock, increasing the temperature, while during the discharge phase, the heat absorbed by the rock is utilized to warm up pressurized water and generate steam, which produces electricity and guarantees maximum resiliency and flexibility for the whole grid.    


The advantages of energy storage

 The use of energy storage systems in the renewable energy field offers a variety of benefits:

  • Environmental protection: adopting green energy storage systems for your home or business helps reduce pollution, accelerate the decarbonization of society and contribute to energy independence for the entire country. 

  • Reduction of energy costs: the ability to store energy at lower costs, to be used during peak demand when prices are higher, leads to significant money savings. 

  • Greater independence: by ensuring a constant and reliable supply of energy, storage systems guarantee efficiency even at times of peak demand.

  • Resiliency: energy storage systems are perfect accompaniments to renewable energy sources because storage systems ensure that green energy is always available, compensating for natural fluctuations in the availability of green energy by storing surplus production, and guaranteeing the distribution of electricity even if the national grid malfunctions. 

Innovation, efficiency, and sustainability: energy storage systems are a key element of the energy transition. In order to be used in an ever more wide-ranging and systematic way, renewable sources will have to make use of increasingly reliable, resilient and digital storage systems, capable of integrating harmoniously with the national distribution grid and thus contributing to energy independence and the safety of the Italian economic system.



A photovoltaic system that includes storage allows the energy produced by the solar panels to be stored in batteries that can convert it (via a chemical reaction) into electricity, which is then deployed as needed.

Storage systems serve to make the most of the solar energy produced. These systems are particularly useful during times of peak solar energy production, allowing electricity to be stored for future use, i.e. during periods of high demand or when weather conditions lead to inconsistent renewable energy generation. This helps optimize personal consumption of solar energy and reduce dependence on the traditional electricity grid.

The quality of the materials and the technologies used can impact the duration, which can vary from 5 to 10 years. After this time, spent storage batteries must be replaced, and recycled and reused in the circular economy to offer environmental and economic benefits.