In Italy, Enel Green Power is testing innovative energy storage systems integrated into renewable plants. This is the way to make sun and wind more plannable and to turn clean sources into a more accessible and usable resource, around the clock.
Sun and wind, the main renewable sources of the new global energy paradigm, are unpredictable and not plannable: the sun disappears at night or goes behind clouds, the wind can’t be programmed with a remote control.
To make renewable sources “predictable” and use them without depending on their natural variability, Enel Green Power has installed special energy storage systems, integrating them into solar and wind plants: solutions that store clean energy when it is produced and allow it to be used when it’s needed.
“Thanks to storage systems, we can be more flexible in our plant management, decrease unpredictability and verify our ability to provide supplementary services to the grid.”
– Luigi Lanuzza, Head of Storage Innovation for Enel Green Power
Innovation that’s “made in Italy”
In order to test these solutions, we selected storage systems (ESS, Energy Storage System) together with advanced management systems for photovoltaic and wind generators.
These innovative storage systems were then installed and integrated into plants we already owned, which were updated for the occasion with the most advanced active management systems with remote operation.
“EGP’s experimental sites are located in Italy, in Catania and Potenza Pietragalla. The first two years of testing demonstrated the ability of storage to limit the intermittency of renewable sources and to increase the possibility of planning them.”
– Luigi Lanuzza
Our first solar field integrated with a storage system with Sodium Chloride Nickel technology (1MW/2MWh) is located in Catania. Since it is a photovoltaic plant, our experiments are mainly oriented toward energy management and supplementary service provision.
The Potenza Pietragalla plant (18MW) is the first of its kind in Italy where a storage system has been integrated with the pre-existing wind field, and is connected to the AT grid. In this case, we use lithium-ion batteries (Samsung, 2MW/2MWh) due to the greater variability of wind, which requires the use of power-intensive batteries that charge and run out quickly.
So much more energy
In just two years of testing, we’ve achieved important results in terms of improvement in production forecast accuracy, with so-called forecast errors reduced by 20-30%.
For a few days, for example, this meant having zero error in photovoltaic, that is, perfect harmony between the production plan and its execution.
These results are even more interesting when we consider that the storage used for the pilot plants is actually of limited size, both in terms of storage (2 hours) and in terms of power (about 11% of wind power in Pietragalla, and about 4% in Catania).
Following these early experiments, the future of storage seems to be unstoppable. Thanks to increasingly affordable costs (-73% compared to 2009), batteries will soon be available in large quantities, will be more efficient in terms of performance (primarily in efficiency of conversion and lifetime) and also more economically sustainable overall, thanks to clear improvements happening in terms of engineering and standardization.
“Until a few years ago, we installed 1 MWh of storage capacity in one container. Today, that capacity has increased fivefold, and it could soon rise even more.”
– Luigi Lanuzza
Technology always moves forward, but in this industry, it takes giant leaps. Following the completion of the first wide-spectrum tests in Italy, we will transfer the know-how we’ve gained to the countries where we work, deciding its application according to the specific business possibilities of the local context.