The surge in hydro output, along with a 40% climb in solar power generation, in turn helped Portugal's power producers slash generation from fossil fuels to their lowest levels since at least 2015, data from think thank Ember shows.
Clean power share of electricity generation in key European countries
That mix of high volumes of clean power and low fossil-fuel use cemented Portugal's status as the third-cleanest major power system in Europe behind Spain and France.
HYDRO HELP
Of the roughly 36 terawatt hours (TWh) of electricity generated by Portugal's power system through November, 8.34 TWh (23.4%) came from hydropower sources, according to Ember.
During the same period in 2022, hydro power generated only 3.78 TWh of electricity, as extensive droughts across much of Europe reduced reservoir and river levels.
Hydro generation recovered in 2023 as rainfall levels rebounded, and was helped further by the deployment of part of a new dam and pumped storage system developed by Spanish energy giant Iberdrola (IBE.MC) along the Tamega river in northern Portugal.
Portugal electricity generation by source
The total installed capacity of the new complex will be 1,158 megawatts (MW), and once completed in 2024 will be combined with two nearby wind farms to form one of the largest energy storage facilities in Europe, according to Iberdrola.
CRITICAL MASS
The completed Tamega giga battery, as it is known, will add almost 900 MW of pumping capacity to Portugal's electricity system, which will provide power producers with the means to balance intermittent renewable power from solar and wind farms with dispatchable clean hydro electricity as needed.
Power firms will also be able to recharge the reservoirs by using cheap renewable-powered electricity to power the system's pumps.
The combination of greater overall hydro capacity along with the heightened ability to balance renewable power flows will further elevate Portugal's clean power share in the years ahead.
Portugal may even overtake Spain in Europe's clean power rankings within the coming years as the full heft of the Tamega complex is added to the country's electricity system.
Portugal's power system already scored a key clean power milestone last month when it was powered entirely by renewables for a record six consecutive days, according to PV Magazine.
That spate of high renewable generation allowed power producers to cut back on gas-powered generation entirely, and also export surplus power to neighbour Spain.
Once the Tamega system is added to the country's power generation mix, additional clean power milestones will likely also be set, further elevating Portugal's standing within Europe as a key driver of regional energy transition efforts.
The opinions expressed here are those of the author, a columnist for Reuters.
