Consumption Peaks and Blackouts in Italy: The Lack of Energy Is Not the Real Cause

On June 23 at 13:30, the Italian electricity grid reached a demand of 55.3 gigawatts, the highest value recorded throughout 2026. This is certified by Terna, the national transmission system operator, through the public portal dati.terna.it, which publishes the country's electricity requirements in almost real-time.

This data arrives amid a heatwave that today, June 29, will peak with highs of 40-41 degrees in the Po Valley and the interior regions of Sardinia. However, during the days surrounding this record, it was not the energy production that faltered: it was the grid that needed to deliver it to homes.

What Terna's Portal Measures

The portal dati.terna.it dedicates an entire section to electricity demand, divided into three parts. The first, total demand, is the overall energy demand that the national electric system must meet at every moment. The second, market demand, counts only the energy fed into the grid by production units participating in the electricity market, including grid losses. The third collects the maximum and minimum peaks (peak and valley) of a given period, with the corresponding coverage by source.

The published numbers follow three levels of reliability. The forecast data is a prediction made the day before based on weather and socioeconomic variables. The provisional data comes from direct measurements by Terna and is continuously updated. Only the consolidated data, published with the statistical yearbook on electricity in Italy, is considered definitive and may require weeks of processing.

To frame the daily figures, an annual reference is needed: in 2023, Italy consumed 281,726.55 gigawatt-hours of electricity, while in 2022, total system demand reached 315,008.40 gigawatt-hours. This same threshold, over 315 terawatt-hours per year, is cited by industry analysts when explaining how much the demand for electricity has increased compared to 115 terawatt-hours in 1970.

The (Still) Unbeaten Record

The historical maximum of required power remains that of July 2015, when demand reached 60.5 gigawatts. Since then, summer peaks have moved to lower values: 58.8 gigawatts in July 2023, 56.9 in July 2024, 55.54 in July 2025. The data from June 23, 2026, fits into this trend, but with a significant difference: it arrived a month earlier than usual, while the summer still had the hottest weeks ahead.

The speed of the increase tells the heatwave story better than any other number. On June 15, national demand was at 45.18 gigawatts: in just over a week, it rose by nearly 10 gigawatts. On Thursday, June 25, at 11:15, the peak was 55.28 gigawatts, 23% higher compared to the first Thursday of the month, when the maximum was stopped at 44.73 gigawatts.

Even looking at the energy consumed, and not just the instantaneous power, the picture is similar. From June 1 to 25, 2026, Italy consumed approximately 23,000 gigawatt-hours, which is 16% more compared to the first 25 days of May. The comparison with previous years is marked: +7.8% over the same period in 2024, +11.5% over 2023. Compared to June 2025, which was also marked by intense heat, the increase was only marginal.

The Problem Is Not Energy, It’s Getting There

The latest Summer Outlook from Entso-e, the European transmission system operators' network, does not list Italy among countries at risk of structural shortages this summer: national production and transmission capacity are deemed adequate. The bottleneck is located further downstream, in the final mile of local distribution, built on a model that anticipated unidirectional flows from producer to consumer and a demand much lower than current levels.

On June 23, half of Turin, from Barriera di Milano to Mirafiori, was without power, with the Civic Palace in the dark for about an hour and a half: local demand had touched nearly 500 megawatts, 40% more than previous weeks. In Milan, it reached 1.52 gigawatts, the highest since 2019. Disruptions were also recorded in Naples, in Pescara, where the absence of power halted wastewater treatment plants, and in several municipalities in Brianza and Comasco.

The mechanism that triggers faults is always the same: the current flowing heats cables and equipment, and the underground cables beneath asphalt and soil fail to dissipate heat. This generates a chain of closely grouped malfunctions that no operator can eliminate in a few hours. Hospitals relied on generators, while Federalberghi Turin considered legal action for the damages incurred by city businesses.

Distribution companies have increased investments to make networks more resilient to heat. Unareti, controlled by A2A and responsible for the Milan network, has budgeted 800 million euros over five years and another 1.8 billion by 2035. Ireti, the Iren subsidiary managing Turin, has launched a 500 million euro plan and deployed an additional 150 technicians. e-Distribuzione, the Enel network serving 7,500 Italian municipalities, has designated 2.8 billion euros for the period 2025-2028, aimed at automation, stronger network grids, generators, and mobile power stations.

Terna, which manages high voltage, has implemented a structured plan for summer 2026 based on the model of the four Rs: risk prevention, preparedness, response, and recovery, with resilience interventions on over 4,000 kilometers of distribution grid and mutual aid task forces between territories for the more complex cases. Over the five-year period, the company allocates about 2.6 billion euros for maintenance and renewal of the network, plus 1.3 billion for digital blackout prevention systems, mandatory since the major blackout in 2003.

The True Driver of Consumption Has Changed, and the Voice of Data Centers Emerges

Air conditioning remains the most visible cause of summer peaks, but it is no longer the only growing segment. By January 31, 2026, the connection requests to the grid from data centers had reached about 79 gigawatts, 85% of all the connection requests submitted by consumption users, distributed over 449 practices concentrated primarily in Lombardy. The same month, national electricity demand grew by 4.1% year-on-year, to 28 billion kilowatt-hours: the highest monthly value since 2014.

On the production front, renewable sources covered 31.7% of the demand in January 2026, compared to 32.3% in January 2025, hindered by a hydroelectric drop of 13.2%. In June 2025, another hot month, renewables reached 48.5% of the demand, with record solar production at 5.7 terawatt-hours: an indication of how solar production during peak daylight hours can ease the grid, just as air conditioning drives consumption to its maximum.

The fact that the peak of June 23, 2026, remains below the 60.5 gigawatts of 2015, although there are more air conditioners installed than ever, is partly explained by more efficient systems. However, growth linked to data centers and electrification does not cease when the heat passes: weather forecasts place the most significant respite only between July 1 and 3, in a scattered order from north to south. In the coming weeks, on dati.terna.it, it will be possible to follow live whether the record of June 23 will hold through the summer months, or fall.