On 23 January, AES Andes announced on their website that they have cancelled plans to build the INNA Project, an industrial green hydrogen and green ammonia project planned near the European Southern Observatory’s (ESO’s) Paranal Observatory, to focus on their renewable energy portfolio instead. Formal confirmation will arrive once the project is officially withdrawn from Chile’s Environmental Assessment Service (SEA, in Spanish).
Last year, ESO publicly raised the alarm about the threat that the INNA megaproject posed to the Paranal Observatory, a site renowned for having the world’s darkest and clearest skies for astronomy and the location of the CTAO’s southern hemisphere array (CTAO-South). The project, proposed by AES Andes, a subsidiary of the U.S. power company AES Corporation, involved multiple energy and processing facilities spread over an area of more than 3,000 hectares, the size of a small city. Its planned location was situated just a few kilometres from the Paranal telescopes. An in-depth technical analysis issued by ESO in March 2025 revealed that INNA’s impact would cause devastating and irreversible damage, particularly regarding light pollution, micro-vibrations, dust, and an increase of the air turbulence in the area.
“While we await the company’s official withdrawal from SEA, we very much welcome this announcement. I would like to extend my deep and sincere appreciation to everyone who advocated for the protection of Paranal’s pristine skies,” says Stuart McMuldroch, CTAO Director General. “The CTAO remains committed to the preservation of dark and quiet skies, and we will continue collaborating with our hosting partners at ESO towards that goal.”
Reflecting on the announced cancellation, ESO has also emphasised the broader lessons this situation provides regarding industrial projects near astronomical facilities. In their press release, they note that “the INNA case and its proposed location highlight 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.” Safeguarding this natural heritage is vital not only for future generations but also for the continued exploration of the Universe by cutting-edge facilities like the CTAO.
Safeguarding this natural heritage is vital not only for future generations but also for the continued exploration of the Universe by cutting-edge facilities like the CTAO.