Public information for hybridizing the Ocaña solar plant with batteries

The Ministry of Sustainable Development of the Regional Government of Castilla-La Mancha has opened the public information process to authorize the hybridization of the FV Ocaña photovoltaic plant with a battery storage system called BESS Ocaña. The announcement, signed by the provincial delegate of Sustainable Development of Toledo, José Rubén Torres Moratalla, on October 15, 2026, is published in the Official Gazette of Castilla-La Mancha number 213, dated November 6, 2026, with official reference 2026/7679 and file number PE-627-CIII.

A 25-megawatt project on a plant already in service

The purpose of the process is the request for prior administrative authorization for the hybridization of the solar photovoltaic electric production facility FV Ocaña, with an installed capacity of 48,600 kW, through an energy storage module and its evacuation infrastructures. The processing is governed by Law 24/2013, of December 26, on the Electricity Sector and Decree 80/2007, of June 19, which regulates the authorization procedures for electrical energy installations of the Government of Castilla-La Mancha.

The project owner is Naturgy Renovables, S.L.U., which presents two administrative documents: “Bess Ocaña. Administrative Project. Municipality of Ocaña” and “Bess Ocaña. Administrative Project. Justification of the control system.” The stated purpose is the production of electrical energy and its discharge into the grid.

The key figures for the module are as follows:

• Total installed power in the battery cell: 25.08 MW.
• Installed storage capacity in direct current: 100.32 MWh.
• Storage system autonomy: 4 hours.

Twenty lithium-ion battery containers and five inversion centers

The planned equipment is organized into twenty twenty-foot Energy Store System (ESS) containers, intended to house the lithium-ion batteries, whose sum of maximum active powers reaches 25.08 MW. Added to these are five “Power Station” skids (PCS) for the direct current to alternating current inversion system and low to medium voltage transformation, each with four 1,375 kW inverters and one 5,500 kVA transformer.

The sum of the maximum powers of the inverters and the transformers connected in parallel is 27.50 MW in both cases. The set is completed with a high-voltage underground network of two RHZ12OL 18/30 kV lines of 50 plus 50 meters, and a prefabricated building that will include a 1,250 kVA auxiliary services transformer, protection cells, and the control, measurement, and low-voltage systems.

The grid connection will be resolved via a 2,801-meter line with two sets of RHZ1-2OL 18/30 kV cables with a 600 mm² cross-section, in an underground trench parallel to the medium-voltage conduits of the photovoltaic plant, up to the Ocaña 30/132 kV Substation.

Location in the municipality of Ocaña and transfer of infrastructure

The storage module will be located within the solar enclosure of the plant to be hybridized, in polygon 24, plots 6 and 9 of the municipality of Ocaña (Toledo). The existing FV Ocaña substation follows a single-busbar single-line diagram at 30 kV and was designed to evacuate 43 MW through a 30/132 kV and 48 MVA transformer; it has two 132 kV line entry-exit positions that allow for the opening of the Aranjuez-La Plata line, in addition to an additional line position. A new 30 kV position for the connection of the battery plant will be installed in its control building.

The announcement also details the 132 kV double-circuit high-voltage overhead line and entry-exit to the Ocaña Substation from the Aranjuez-La Plata line, measuring 945.39 meters, divided into five sections:

• Gantry-Tower 1: 77.02 meters.
• Tower 1-Tower 2: 235.37 meters.
• Tower 2-Tower 3: 289.76 meters.
• Tower 3-Tower 4: 285.71 meters.
• Tower 4-Tower 5: 57.52 meters.

Tower 5 was processed in an independent file owned by UFD Distribución Electricidad, S.A., with reference 2101/00280 (E-45211122925). Part of the 132 kV switchyard and this line will be transferred to said distributor.

Allegations within a period of twenty days

The file may be examined at the Provincial Delegation of Sustainable Development of Toledo, at calle Huérfanos Cristinos, 5, Toledo, as well as at the web address enabled by the Junta. Any allegations deemed appropriate may be submitted within a period of twenty days starting from the day following the publication of the announcement.

The hybridization of existing photovoltaic installations with storage is one of the ways the renewable sector improves the integration of solar production into the grid and shifts energy curtailment to hours of peak demand. In the case of Ocaña, the module will allow for the accumulation of up to 100.32 MWh alongside a 48.6 MW plant, an operation that affects the energy planning of the Corredor de la Sagra and the surrounding municipalities, and whose schedule will now depend on the result of the public exhibition and the regional authorization.

Source: Official Gazette of Castilla-La Mancha, no. 213, November 6, 2026, section V (Other official announcements), pp. 39307-39308 (official reference: 2026/7679).