Chile loses thousands of GWh of renewable energy generation annually due to insufficient system capacity to absorb it, with losses reaching up to 50% in some cases. This scenario reflects a system that has grown in generation capacity but not in transmission capacity, demand capacity, or flexibility.
“If we compare the demand for electricity, we have an average curtailment of 10-11%, but there are situations and projects that have up to 50%; so we already have almost 6300 GWh/year of ERNC curtailments,” stated the executive director of the Chilean Association of Renewable Energies and Storage (ACERA), Ana Lía Rojas, to the microphones of the streaming “It had to be said and it was said” .
The imbalance is operational and structural: during the day the system is saturated with clean energy, but at night it depends on thermal generation, which means "decarbonized day, carbonized night", evidencing a critical inefficiency.
“Spills are not a 'failure' of renewable energy. They are an economic and operational sign that the electrical system is not growing at the same rate,” the specialist explained.
The phenomenon is also territorial and seasonal. The Antofagasta (almost 650 GWh) and Atacama (450 GWh) regions concentrate the surpluses, while the cuts intensify in months of high solar radiation.
In this context, batteries are no longer just a promise and are beginning to have a direct impact on the operation of the system, to the point that with 1.6 GW operational by the end of 2025, they allowed "a reduction of about 10% of the projected cuts", according to data from ACERA.
To date, nearly 2 GW of BESS have been installed, with an average operating time of 4.5 hours. In addition, 1.8 GW (7.1 GWh) are currently being tested, and another 6.3 GW (29 GWh) of batteries are under construction.
While there are 16 GW BESS in environmentally approved processes and 12.6 GW in different stages of environmental qualification, most of it hybridizing solar projects (13890 MW between both registries) and also wind projects (1649 MW BESS between approved and in qualification).
“Battery absorption capacity will be very important to reduce waste disposal by 10-15%; although there is still much room to manage waste disposal not only with batteries. However, the problem cannot be solved solely with storage, but also with stimulating electricity demand, among other things,” Ana Lía Rojas explained.
What will determine the implementation of approved and qualified BESS projects? Bankability and revenue from arbitrage in the energy market, which, according to the interviewee, will decrease as more units are incorporated into the same nodes.
“Therefore, beware of the risk of cannibalizing the market and that, by installing so many batteries at the same node, the sustainability of projects that were evaluated individually and considered the systemic effect could be affected,” he warned.
New markets: the true value of storage
For that same reason, the executive director of ACERA argued that the arbitrage limit forces a redefinition of the role of storage in the electricity system and recommended looking for other markets where batteries are remunerated, including contributions to sufficiency and complementary services.
“In the first case, we are in an incipient discussion because we are not debating how to remunerate the units that contribute to the sufficiency of the system but are also decarbonized and clean,” Rojas stressed.
“While for the ancillary services market, we are already seeing solar and wind participation, especially in secondary and tertiary frequency control. And in the first months of 2026 we expect battery participation,” he added.