Wind and solar power to keep the lights on in Ecuador
Empty reservoirs caused disrupted energy supply
Researchers from the Vrije Universiteit Brussel (VUB) in Belgium and Yachay Tech University in Ecuador have come to a surprising conclusion: wind and solar energy, often criticised for their lack of predictability and dependence on the weather, could make Ecuador’s power supply substantially more reliable. Currently, its power supply relies on large hydroelectric power stations. Recent decades saw an increase in dam construction, boosting electricity generation and driving economic growth. But things changed in the last years. During a weak rainy season in 2023, water levels in the reservoirs began to drop. Rainfall in 2024 was even weaker, and as a result, reservoirs ran nearly empty.
The country had to make emergency purchases of diesel and gas as alternative energy sources, but this was insufficient. For months, Ecuadorians had to endure power cuts of more than 12 hours a day. The economy suffered enormous damage in the energy crisis. According to witnesses, many Ecuadorians felt like being “back in the 18th century”. The cause of the disaster was clear: Ecuador’s overdependence on hydropower, increasingly affected by droughts due to climate change.
“The production of wind and solar power can, of course, fluctuate strongly from day to day,” explains Professor Sebastian Sterl (VUB), lead author of the study. “But on a seasonal level, this is not the case. In some months of the year, the wind is always stronger than in others, just as some months are always sunnier than others. These patterns recur every year, unlike the rainy season, which can fail.” If large-scale wind and solar farms were built, this knowledge could help adapt reservoir management to better withstand dry periods.
“Ecuador could refill its reservoirs more quickly in the months when wind and solar plants reach peak production—since the need for hydropower to meet demand is reduced during that time,” says Tinne Mast (VUB), a colleague of Sterl and co-author of the study. “In very dry years, this could prevent a crisis scenario. Instead of depleting the reservoirs to the last drop, wind and solar power would be used to bridge the failed rainy season.”
In other words: wind and solar extend the availability of hydropower in time. Using energy model calculations, the researchers show that a buildout of wind and solar plants could largely avoid a repeat of the Ecuadorian energy crisis of 2024. This would require installing around 500 megawatt of capacity for wind and for solar each—for comparison, Ecuador’s largest hydropower plant has a capacity of 1500 megawatt. Thanks to the synergies between wind, solar, and hydro, this would reduce the unmet demand in extremely dry years by 90%, without Ecuador having to import a drop of additional fuel.
Towards a resilient Ecuadorian power system
Not only is the overall electricity generation boosted by wind and solar—in dry years, these energy sources also increase the power grid’s capability to respond to demand at peak times. This is a surprising discovery, because wind and sun normally contribute very little to peak capacity. After all, there is no guarantee that it will be windy or sunny at those times. “But what can be guaranteed, is that the reservoirs fill up better thanks to their interaction with wind and solar,” explains Sterl. “This prevents hydropower plants from becoming inoperative due to low water levels, and as a result, their peaking capacity is no longer lost during extreme droughts.”
According to the research team, this resilience strategy could serve as an example for other countries that are heavily hydropower-dependent. “This is hugely relevant in Latin America,” says Professor Luis E. Pineda of Yachay Tech, who co-authored the study. “Colombia, Venezuela, Brazil, Paraguay, Costa Rica...: their power generation comes largely from hydropower and is vulnerable to droughts, which could be mitigated by combining hydropower with solar and wind power. But elsewhere too, for example in Norway, Canada and China, dry periods have led to energy problems in recent years.”
With the frequency and severity of droughts projected to increase with rising global temperatures, and in the context of an increasingly unstable geopolitical world order, reducing the need for “emergency” procurement of fossil fuels during droughts is an example of climate resilience as well as of national security.
Their findings were published in the leading journal Nature Water in a paper entitled “Variable renewables fortify Ecuador’s power system against recurrences of drought-driven energy crises”.
Full reference: Sterl, Pineda, Mast, Rodriguez, Muñoz, and Thiery, 2026, Nature Water, https://doi.org/10.1038/s44221-026-00617-w.
Contact:
Lead Author: Prof. Dr. Sebastian STERL
Tel: +32 2 295 62 73 / +31 6 1737 5796
Email: sebastian.sterl@vub.be
