AES Andes announces cancellation of INNA, the industrial complex planned near Paranal

AES Andes announced that it will step back from the megaproject INNA, planned to be located near the European Southern Observatory’s (ESO’s) Paranal Observatory. ESO welcomes this announcement and expects that the project will be withdrawn from Chile’s Environmental Assessment Service (SEA) soon, which would formally confirm INNA is not going ahead.

“When the cancellation is confirmed, we’ll be relieved that the INNA industrial complex will not be built near Paranal,” said ESO Director General Xavier Barcons. “Due to its planned location, the project would pose a major threat to the darkest and clearest skies on Earth and to the performance of the most advanced astronomical facilities anywhere in the world.”

AES Andes, a subsidiary of the US company AES Corporation, announced that they had decided to discontinue INNA, a green hydrogen and green ammonia project, to focus on their renewable energy portfolio instead. A detailed technical analysis by ESO last year revealed that INNA would cause severe, irreversible damageto the dark skies of Paranal and to the capacity of its facilities to operate as designed. The most significant impacts, affecting facilities such as the Very Large Telescope (VLT), the VLT Interferometer (VLTI), the Extremely Large Telescope (ELT), and CTAO-South, would be caused by light pollution, micro-vibrations, dust, and an increase of the air turbulence in the area.

“As we have said before, ESO and its Member States are fully supportive of energy decarbonisation and initiatives that ensure a more prosperous and sustainable future. Green-energy projects — and other industrial projects that drive national and regional development — are fully compatible with astronomical observatories, if the different facilities are located at sufficient distances from one another,” says Barcons.

The INNA case and its proposed locationhighlight the urgent need to establish clear protection measures in the areas around astronomical observatories. Such measures are essential to allow astronomical observatories to continue operating, particularly in a region widely regarded as the best in the world for optical astronomy facilities, owing to the exceptional darkness of the skies over northern Chile.

“We will continue to work in close collaboration with local, regional, and national authorities to protect the dark skies of northern Chile, an irreplaceable natural heritage that is essential for advancing our understanding of the Universe and to enable world-class astronomy for the benefit of Chile and the global scientific community,” says Itziar de Gregorio-Monsalvo, ESO’s Representative in Chile.

“It has been incredibly reassuring to see so many people in Chile and around the world care deeply about, and actively speak up for, the protection of dark and quiet skies in the context of the INNA project,” says Barcons. “We are sincerely grateful for this engagement and solidarity. It gives us confidence that, by working together, we can continue to protect dark and quiet skies in Chile and elsewhere — for astronomy research and for humankind.” Since the project was submitted to SEA in December 2024, members of the astronomy community in Chile, in ESO’s Member States and beyond, political leaders and authorities at international, national, regional and local level, as well as countless members of the public, have made their voices heard in support of this shared goal.

ESO will continue to intensify its efforts to ensure that the pristine skies of Paranal remain the world’s best window to observe the Universe, and is also committed to the broader fight against light pollution and satellite interference, helping secure the natural heritage of dark and quiet skies around the world for future generations.

More information

The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration for astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, Czechia, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as survey telescopes such as VISTA. Also at Paranal, ESO will host and operate the south array of the Cherenkov Telescope Array Observatory, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates ALMA on Chajnantor, a facility that observes the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.

Links

• Executive summary of ESO technical analysis on the impact of the INNA project
• Photos of Paranal
• INNA infographics
• Previous press releases on INNA: January 2025; March 2025