Chile’s grid operator, the Coordinador Eléctrico Nacional (CEN), granted grid-connection authorization on 31 August 2026 for a 356 MW/2,136 MWh battery energy storage system to be built alongside Enel Green Power Chile’s Guanchoi solar plant in the Atacama region. At a six-hour discharge duration, the system would connect at the Bella Mónica substation (33 kV) in the Diego de Almagro commune, Chañaral Province. The authorization sets September 2027 as the deadline for Enel to formally declare the start of construction, and grants indefinite grid-capacity rights once the system is connected — a regulatory milestone, not a construction start or confirmed final investment decision.
The battery system would be integrated with the existing Guanchoi solar plant, a 398 MW facility that began commercial operation in July 2023 as, at the time, Chile’s largest solar plant. Guanchoi produces around 1,100 GWh a year and connects to the grid via an 8 km transmission line to the Illapa substation. Combining the plant with storage would let Enel shift more of that output to hours when the grid needs it, rather than exporting it only when the sun is up — a increasingly common pairing in northern Chile’s solar-heavy grid.
If built at its authorized capacity, Guanchoi’s battery system would be Enel’s largest in Chile by a wide margin. As of mid-2026, the company’s existing and under-construction Chilean battery portfolio totaled about 730 MW across six projects: Finis Terrae (100 MW, grid-forming, paired with Enel’s Finis Terrae solar plant in Antofagasta), Las Salinas (205 MW), Azabache (94 MW), and three smaller operating systems — La Cabana (34 MW), Don Humberto (67 MW), and El Manzano (67 MW). Guanchoi alone, at 356 MW, would be roughly half that combined total. As with its other Chilean battery projects, Enel has not disclosed a battery technology supplier or EPC contractor for Guanchoi; trade press covering the company’s BESS buildout in Chile has noted that Enel typically does not reveal its battery suppliers.
The project sits within a fast-growing national pipeline. Chile had 4.7 GW of battery storage (19.2 GWh) under construction as of June 2026, representing roughly $3.86 billion in investment and putting the country about 35% of the way to its 2030 target of 6,000 MW of installed storage, according to pv magazine Latinoamérica’s tracking of the sector. Other developers active in the Atacama region alongside Enel include AES Andes (with its Pampas, Atacama II, and Cristales hybrid projects), Grenergy (developing the 430 MW Elena Phase I, among the largest BESS projects currently under construction in the country), Atlas Renewable Energy, and Colbún.
One figure worth flagging with a caveat: a single source (pv magazine Latinoamérica) referenced a roughly $350 million investment for the Guanchoi storage system, tied to an April 2026 meeting between Enel and Chile’s Ministerio de Bienes Nacionales — the ministry that manages state land use, which would be relevant here given the project’s location on land in the Atacama desert. I could not independently corroborate that figure through a second source or an Enel press release, so it should be treated as provisional pending confirmation.
On the point about press releases specifically: I could not find a dedicated Enel Green Power Chile press release announcing the Guanchoi BESS grid-connection authorization, unlike several of the company’s other Chilean battery projects (Azabache and Finis Terrae both got formal construction-start press releases). This authorization appears to have surfaced through regulatory filings and trade press coverage rather than a company announcement — worth another check closer to any construction-start or FID news, when Enel would be more likely to issue one.
