“The manipulation of the electricity market by the usual suspects continues without the Authority lifting a finger.” Carlo Calenda returns to the attack on energy prices and this time announces a further step: in addition to a new parliamentary question, Azione is preparing a complaint to the Public Prosecutor’s Office. “Let’s put an end to this unprecedented disgrace on the lives of citizens”, wrote the leader of Action on social media on 28 September.
The manipulation of the electricity market by the usual suspects continues without the Authority lifting a finger. Today we will file a further question. But at this point it is no longer enough, we will prepare a complaint to the public prosecutor’s office. Let’s put an end to this filth… https://t.co/pNGPukVGHv
— Carlo Calenda (@CarloCalenda) September 28, 2026
The basis of the complaint is a new analysis by Giuseppe Zollino, associate professor of energy technology and economics at the University of Padua and head of Energy Action. Zollino focuses attention on what happened in the afternoon and evening of Sunday 27 September. According to his calculations, between 5pm and 9pm the marginal price of electricity would have been around 40-140 euros per megawatt hour higher than the cost of energy produced by a gas power plant. Hence his conclusion: in those hours it would not have been the gas plants that determined the marginal market price.
In support of the thesis, Zollino cites Terna’s real-time data. At 6pm on 27 September, thermoelectric power was producing around 12.6 GW, while imports from abroad were worth 5.6 GW, hydroelectric power 3.75 GW, photovoltaic power 2.53 GW and wind power 2.05 GW. Two days earlier, on 25 September, another screen of Terna’s “Energy Balance” showed a thermoelectric production of around 24 GW at 9.15pm. It is precisely this gap that fuels Zollino’s suspicions: if the plants had been able to produce almost double just 48 hours earlier, why wasn’t such a large part of the capacity producing on Sunday evening?
The comparison, however, requires caution. The two images photograph different days and times and show actual production, not the technically available capacity of individual power plants. From these numbers alone, it is therefore not possible to establish whether the plants were down due to faults, maintenance, technical or economic constraints or whether part of the available capacity was voluntarily removed from the market. And it is precisely here that Zollino’s accusation is concentrated. According to the teacher, it would be difficult to explain a difference of the order of 11 GW solely with technical unavailability. The hypothesis put forward is that of the so-called “capacity retention”: potentially available power plants that are not offered, or are offered at prices that do not enter the market, leaving room for more expensive plants and thus increasing the marginal price.
European Remit rules prohibit manipulation of energy markets. Even the so-called capacity withholding can become a manipulative conduct when an operator capable of influencing the price avoids without legitimate justification to offer available production capacity on the market that would be economically convenient to use. However, it does not mean that every power plant that stops, or every high offer automatically constitutes an offense: actual availability of the plant, costs, technical constraints and operator behavior must be assessed.
To move from suspicion to proof, data on the individual offers presented by operators are needed. And that data is not yet publicly available today. In fact, the Energy Markets Manager keeps the information relating to purchase and sale offers presented on the Day Ahead Market confidential for seven days. Only at the end of that period will it be possible to precisely reconstruct which plants offered energy, how much they offered and at what price.
Furthermore, the issue comes while the Authority is already under pressure on electricity prices. In August Arera announced the strengthening of market supervision after the PUN blaze, specifying however that at that time no anomalies had emerged that could explain the increases, attributed mainly to the scarcity of gas, the high demand and the production difficulties recorded in Europe.
The precedent: when Arera sanctioned an operator