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heat = "#c8553d"
cold = "#1478b8"
fmt = d3.format(",.0f")
gw = v => (v / 1000).toFixed(1)
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completos = data.anual.filter(d => d.completo)Four decades of peak demand
The maximum demand of Argentina’s interconnected grid since 1980: how fast it grew, and when the yearly peak moved from winter to summer. Built only from open public data.
NoteResumen en castellano
La demanda máxima del SADI desde 1980, solo con datos abiertos. Pasó de 4,7 GW en 1980 a 30,3 GW en 2025, seis veces y media más. Hasta 2000 el pico anual fue siempre de invierno; desde 2014, el pico de verano supera al de invierno todos los años, hoy por alrededor de un 8 %. Abril y octubre se convirtieron en valles profundos: su pico es hoy un tercio menor que el máximo del año. El factor de carga cae desde mediados de los 2000: la demanda máxima crece más rápido que la energía.
Today’s numbers
The yearly peak, 1980–2025
Each point is the year’s maximum demand, coloured by the season in which it happened.
Winter peak against summer peak
The highest demand of each winter (June–August) and of each summer (December–February, labelled with the year in which it ends).
The shape of the year, decade by decade
Each month’s peak as a share of its year’s maximum, averaged over each decade (2020 is left out because of the lockdown). The winter hump of the 1980s gives way to two humps, and in the 2020s the summer one is the highest.
Load factor
Average demand over the year divided by its peak. A lower value means a spikier year: more capacity that is only needed for a few hours.
My reading
New · 2026-10-10
Six and a half times in 45 years. The peak demand of the grid grew from 4.7 GW in 1980 to 30.3 GW in 2025. It grew fastest in the 1990s (6.7 % a year), slowed to 4.2 % in the 2000s and to 2.2 % in 2010–2020, and has picked up again since 2020, to about 3 % a year.
The season of the peak changed, and it can be dated. Until 2000 the yearly peak was always a winter one, set by heating and lighting on cold evenings. Summer peaks caught up during the 2000s: they exceeded the winter peak in isolated years (2001 and 2002, when the crisis depressed winter demand, and 2012), and since 2014 they have done so every single year, today by about 8 %. Argentina’s grid has been a summer-peaking system for more than a decade. It is the same change that the temperature panel shows from the other side: the response to heat grew faster than the response to cold, with its largest step in the late 2010s.
The shoulder seasons became deep valleys. In the 1980s every month’s peak was within about 13 % of the year’s maximum: demand was high all year, with a winter hump. Today the year has two humps, summer and winter, and two valleys. The peak of April fell from about 90 % of the yearly maximum (1980s to 2000s) to 81 % in the 2010s and 67 % in the 2020s; October, from about 90 % to 73 %. In autumn and spring, a third of the capacity needed for the yearly peak is not needed even at the busiest hour of the month. That is the natural window for maintenance of power plants and lines, and it is growing.
The year got spikier. The load factor has been falling since the mid-2000s, from 0.66 in 2004 to 0.53 in 2025: the peak grows faster than energy. For the grid, that means more generation, transmission and distribution capacity that is used only a few hours a year. Where capacity is needed for few hours, storage and demand response are most valuable, and the cost of that capacity weighs more on the price of each MWh.
Method and sources
- Peak demand. Monthly maximum demand of the interconnected system (an instantaneous value, in MW). 1980–2000 from the Secretaría de Energía series; 2001 onwards from the Ministerio de Economía series. In 2001–2017, where both exist, they coincide in 92 % of the months and in the yearly maximum of every year except 2010 (100 MW apart).
- Load factor. Total energy demand of the year divided by the yearly peak times the hours of the year, 2001 onwards (complete years). Because the peak is instantaneous, its level is somewhat lower than a load factor computed with hourly averages; the trend is what matters.
- Seasons. Winter peak: highest of June–August. Summer peak: highest of December–February, labelled with the year in which the summer ends. The colour of the yearly peak uses May–September for winter and December–March for summer.
- This page does not offer the data for download. To obtain the data, go to the sources:
- Secretaría de Energía, Potencia máxima del sistema eléctrico 1980–2017, on datos.gob.ar (CC BY 4.0).
- Ministerio de Economía de la Nación, Subsecretaría de Programación Macroeconómica, Demanda de electricidad, on the national open data portal, datos.gob.ar (CC BY 4.0).