Alto Maipo Completes Tunnel Excavation

March 4, 2021

Today, a fundamental milestone both for the project and the country in its decarbonization process has been obtained.

Santiago, March 4, 2021.- Alto Maipo, the most important renewable energy project in Chile, completed today at 11:30 am the excavation of its tunnels with an extension of 74.6 kilometers.

The construction of the tunnels was carried out using state-of-the-art technology according with the highest engineering standards, including among the most important ones, the use of TBMs (Tunnel Boring Machines) specially designed according to the geology of the area. The Alto Maipo run-of-the-river project, made up of Las Lajas and Alfalfal II (531 MW), is a fundamental part of the Greentegra strategy and key to the decarbonization of Chile. With an expected generation of 2,200 GWh per year, equivalent to the consumption of more than 1,000,000 households, Alto Maipo will deliver emission-free energy to Santiago, the country’s main consumption center.

With this new milestone, the geological risk of the construction will be eradicated and the project will enter its final stage to start commercial operation in the second half of this year.

“As we announced last week with the delivery of our financial results, today is a great day for Alto Maipo, since the excavation has been completed and the last phase of construction has begun. We are only a few months away from injecting renewable energy into the country’s main consumption center. This gives us great pride and satisfaction,” said AES Gener’s CEO, Ricardo Falú.

The executive, together with Bernerd Da Santos, Executive Vice President of AES, and Julián Nebreda, President of AES Gener and of the South America business unit, thanked “all the staff of the project who helped make this great engineering work a reality” and highlighted that “Alto Maipo is vital in Chile and will play a fundamental role in decarbonizing its energy matrix”.

It should be remembered that when excavating the Volcán tunnel, the team of Alto Maipo reached the South American excavation record of 56.9 meters in one day with the TBM.

The energy produced by Alto Maipo will be added to the run-of-the-river power plants belonging to the AES Gener Cordillera Complex (Alfalfal I, Maitenes, Queltehues and Volcano) and will be injected into the National Electrical System (SEN).

In addition, once Alto Maipo is completed, we plan to expand the Virtual Reservoir (batteries) solution to 1,250 MWh.