Storage and Renewables: Enel Green Power Projects in Italy Set the Standard

Published on Thursday, 6 April 2017

The EGP projects that integrate electricity storage systems with renewable plants have been selected as best cases by the white paper “Prospects of electrochemical storage systems in the energy industry”, released by RSE-Ricerca Sistema Energetico (Energy System Research) and ANIE Energy

Electricity storage and renewable plants. The success of this combination can open unthinkable frontiers for the entire energy industry and is a new revolution for the world of renewables, solar and wind especially.

Storage and renewables are gaining attention and investments in many countries. Also for this reason, ANIE Energy and RSE - Ricerca sul Sistema Energetico (Energy System Research), with the collaboration of Enel Green Power, Innovation and the Polytechnic of Milan have released a white paper on “Prospects of electrochemical storage systems in the energy industry”.

Now in its second edition and presented in Rome (Italy) on 5 April, the research offers a look at the objectives and advantages of storage projects underway in Italy.

“Some of the important cases mentioned in the white paper are the Enel Green Power projects in Potenza Pietragalla and Catania, where we’ve integrated storage systems with renewable plants.”

Integrating Renewables and Storage Systems

In Catania (Sicily, Italy), we opened our first pilot project with a steady storage system integrated with a commercial-sized renewable plant in 2015.

The Enel Green Power solar farm holds a storage system for up to 1MW/2MWh integrated into the Sicilian photovoltaic plant with 10 MWp, with power limited a 8 MW because of grid constraints, in turn updated with advanced technological solutions that increase its flexibility and run remotely for full integration with the storage.

The technology – which is energy oriented – is optimal for the low randomness of the photovoltaic yield, while permitting fast compensation in case of unexpected changes in production.

“The energy storage system integrated by EGP at the Potenza Pietragalla wind farm (Basilicata, Italy) was the first plant of its kind in Italy.”

Opened in 2015, it represents an important step forward for the entire technology value chain of wind energy and, more generally, for renewables.

The storage system at Potenza Pietragalla (2MW/2MWh), integrated into the Enel Green Power wind farm, allows us to compensate for the intrinsic unpredictability, typical of wind resources, helping to guarantee the stability of the electrical grid.

For both projects, the experience was extremely positive, since it was possible to considerably reduce the imbalances associated with prediction errors for functioning plants, reduce power peaks by mitigating the characteristic intermittency of non-programmable renewable energy sources, maximise the energy fed into the grid when facing limited transport capacity, in addition to studying the possibilities of providing ancillary services to the electrical grid.

The Integration of Storage on Islands

One of the examples cited in the white paper was Enel’s project on the island of Ventotene, launched in May 2016.

The energy storage system developed by Enel on the island off the coast of Lazio aims to reduce fuel consumption, optimise generation efficiency and increase the rate of non-programmable renewable generation, meeting the needs of the island and guaranteeing reduced CO2 emissions.

The island of Ventotene is characterised by strong seasonal and daily variability in the electrical load, so it was equipped with a 300 kW / 600 kWh lithium battery by Enel, integrated into the island’s generation plant.

In its first months of operation, the system has provided excellent results, presenting a high degree of availability and guaranteeing an elevated quality of electrical service, with a reduction in fuel consumption of about 15%.