Over the past decade, Chile has made progress in closing coal-fired power plants and expanding clean energy sources such as solar and wind power, in pursuit of its goal of carbon neutrality by 2050. This development has positioned the country as one of the leaders in renewable energy in South America. However, it has not been without challenges.

At peak solar energy generation times, Chile’s transmission grid is unable to absorb all of the energy it receives from the north, where most solar generation is concentrated. This leads to energy losses, a phenomenon known as curtailment. The Ministry of Energy’s 2023-2027 Transmission Expansion Plan states that the current limitations of Chile’s transmission infrastructure mean areas with available capacity need to be prioritised while new transmission systems are being planned.

Recent data from the National Electricity Coordinator (CEN) shows the northern region of Antofagasta makes the highest demands on Chile’s national electricity system, mostly due to being the world’s most productive copper mining region. But electricity demand is also growing rapidly in the central regions of Metropolitan Santiago and Valparaíso. Here, major urban centres account for a large share of that consumption. As a result, renewable energy plans now abound in central Chile.

In 2023, solar projects worth almost USD 2 billion entered the environmental approval process in these two regions.

“Many solar plants have begun to be installed in central Chile for several reasons, but the most important is curtailment,” says Jorge Leal, a partner at the solar power development firm LAS Energy, and a specialist in renewable energy and the electricity market. “This phenomenon is mainly due to transmission restrictions from the north to the centre.”

In the municipality of Tiltil, 60 kilometres north of Santiago, several solar facilities have already entered operation. These include the Ovejería and El Litre solar parks, both with an installed capacity of nine megawatts (MW), and the 99 MW El Manzano solar plant.

There are also several larger-scale projects under construction in Tiltil, including the 200 MW Don Patricio Photovoltaic Park. The development will be operated by Pacific Hydro Chile, a subsidiary of the Chinese state-owned State Power Investment Corporation. Pacific Hydro has been active in Chile since 2002 and developed multiple renewable energy projects, such as the 82 MW Punta Sierra wind farm, in the central region of Coquimbo.

Don Patricio has been under review by Chile’s environmental impact assessment regulator since 2024. This process has raised potential problems with the project – and communities that could be affected are paying attention.

Solar and storage at Don Patricio

The Don Patricio project represents a USD 368 million investment to install 269,832 solar modules. Its design also features a battery energy storage system (BESS) which, according to Pacific Hydro, is essential for ensuring a more “flexible and sustainable” energy mix: the high-capacity batteries used in a BESS allow for “the optimisation of energy from renewable sources … delivering it when it is most needed”.

The project incorporates 42 transformer stations, an electrical substation and a 1.17-kilometre transmission line. The energy generated will be fed into Chile’s national electricity system (SEN), which means it will be consumed both locally and further afield.

According to the environmental impact study submitted to the Environmental Assessment Service (SEA) at the end of 2023, Don Patricio’s construction area will cover 226 hectares in Santa Matilde, an agricultural area of Tiltil. In addition to the panels, access roads, internal roads and a work site facility will be built.

Solar arrives in ‘sacrifice zone’

Tiltil is a rural commune with a population of 19,742 recorded in 2024. The area combines small urban centres with scattered agricultural and industrial areas, where crops coexist with mining and other industrial projects.

According to the local authority itself, the commune faces a significant environmental burden of 49 pollution sources, corresponding to various companies operating in the territory. These include landfills, pork production and olive processing, as well as mining, cement, and industrial waste works.

Tiltil also faces serious water problems. Research by the Pontifical Catholic University of Chile’s Institute of Urban and Territorial Studies ranked it among the Chilean municipalities to have issued the highest number of water shortage decrees. These are issued by the General Directorate of Water (DGA) and designed to unlock emergency water extraction and delivery powers to aid rural populations for six months. In some areas of Tiltil, residents permanently depend on lorries transporting water to them.

Dialogue Earth spoke to Nicolás Jofré, a Tiltil resident and former spokesperson for the Movement for the Defence of Access to Water, Land and Environmental Protection (Modatima). He claims that “industrial projects continue to be added to a territory that already has some of the most severe environmental damage in Chile.”

A study released this year by the Pontifical Catholic University of Chile detected metal contamination in Santa Matilde and neighbouring Polpaico. The metals included arsenic, copper, chromium, manganese, lead, nickel and zinc, some of which pose cancer risks.

Another Tiltil resident, who asked to remain anonymous, told Dialogue Earth that the majority of their neighbours were not in favour of any more industrial projects being established in the area.

A farmer tends to his harvest in Tiltil. In this small commune, farming operations must coexist with mining and other industrial projects, which leads to the depletion of natural resources and pollution problems (Image: Oscar Ordenes / Ministerio de Economía, Fomento y Turismo de Chile, CC BY NC ND)

The potential impacts

For Modatima’s Jofré, solar projects, although clean in terms of electricity generation, do not alleviate local problems: “We consider it an abuse of the poor, an abuse of those who do not have the strength to raise their voices and defend themselves.”

One of the critical points of the environmental impact study is Don Patricio’s likely impact on native forests. Pacific Hydro acknowledges the felling of 1.1 hectares of “native forest” and 0.6 hectares of “native preservation forest”. This submission has been questioned by the National Forestry Corporation (Conaf), which reviews all baselines, impact assessments and mitigation or compensation measures for projects submitted to the Environmental Assessment Service. Conaf’s forestry inspection and environmental assessment manager, Bernardo Martínez, thinks these initial measurements “could be underestimated”.

This situation could be due to a problem with stand identification – the methods used to describe the characteristics of forest and environmental resources – or because not all interventions and habitat alterations were correctly identified by the company, Martínez tells Dialogue Earth.

Martínez adds that the impacts are not limited to the vicinity of the project. He highlights concerns about potential photovoltaic heat islands, as well as the changes in temperature, wind and humidity generated by large solar panel installations that “threaten vulnerable native species”. He also mentions the “edge effect”, which refers to changes in light, humidity and temperature conditions in the transition zones between the forest and the solar park.

Among the vegetation species that the impact study identifies as being affected are guayacán (Porlieria chilensis) and algarrobo (Prosopis chilensis). These small trees are resistant to arid climates but require relatively stable habitats and sufficient water availability to survive. In a territory of water scarcity, Martínez says “their loss could have consequences for local biodiversity and the provision of ecosystem services.”

Dialogue Earth spoke to Flavia Liberona, executive director of the Terram Foundation, a Chilean civil society organisation dedicated to sustainable development. She says what is happening in Tiltil reflects a broader tension in the country: “The balance between energy transition, biodiversity protection and territorial justice remains one of the central challenges on Chile’s environmental agenda.”

Similarly, Gonzalo Melej of the NGO Chile Sustentable tells Dialogue Earth the energy transition must be mindful of territorial planning, to avoid social conflicts and damaging the reputation of clean energy: “We are seeing how solar plants installed on agricultural land compete with food production, and other land uses, currently generating conflicts and a loss of social legitimacy for these clean electricity generation technologies.”

A photovoltaic park in the Atacama Desert. This region of northern Chile experiences high levels of solar radiation, and is also the world’s most productive source of copper – a large part of the solar power generated here is absorbed by the copper industry (Image: Francisco Javier Ramos Rosellon / Alamy)

The future of the project

For now, the Don Patricio solar park remains under environmental assessment. Pacific Hydro indicated it cannot provide further details while this process is ongoing. “There is not much we can say about the Don Patricio project, as it is still in the development stage and under environmental assessment,” María Susana Muñoz, Pacific Hydro’s corporate affairs and sustainability manager, tells Dialogue Earth.

However, in the project evaluation process file, Pacific Hydro responds to some of the observations made by Conaf and other agencies.

The company proposes the use of bischofite, a chemical compound that can be used to stabilise unpaved roads. This would serve as a mitigation measure against the spread of particulate matter, generated by increased vehicle traffic linked to the project and its construction. The file also proposes the installation of acoustic barriers to reduce noise impact, and biodiversity compensation measures through the planting of native species.

Meanwhile, Jofré is sceptical. Despite being surrounded by solar parks, the inhabitants of Tiltil continue to pay very high electricity rates. According to a January 2025 report, the municipality had recorded a 94% increase in prices since June 2024. This steep rise marked the end of a national electricity rate freeze that was initiated approximately five years ago. “We pay one of the highest electricity bills in Chile,” Jofré points out.

The Don Patricio case reflects Chile’s dilemma: how can the country move towards carbon neutrality without sacrificing biodiversity, fragile ecosystems and social justice? The answer, for now, remains under debate.