Published in La Tribune, on June 12, 2026
In its decision of April 9, 2026, the French Energy Regulatory Commission (CRE) approved new rules designed to control voltage on the French power grid. These rules, developed by the electricity system operator (RTE), follow the Iberian blackout of April 28, 2025, which reminded us that it is impossible to guarantee 100% electricity supply to meet ever-growing energy demand at an affordable cost.
Settling the Score in Iberia
Now that the two ENTSOE reports (October 3, 2025, and March 20, 2026) on the Iberian blackout of April 28, 2025, have been thoroughly reviewed, the time has come to find one (or several) scapegoat(s) to blame and to whom to demand payment for the damages incurred. The Spanish grid operator and the power producers are passing the buck back and forth. The energy regulator (National Commission for Markets and Competition, CNMC) and the government are trying to convey a message of their complete innocence, but the political opposition is seizing the opportunity to lambast the incompetence of the current authorities.
Since April 17, 2026, the CNMC has opened more than 60 proceedings against various electricity generation facilities (combined-cycle, renewable energy, and nuclear) and the system operator Red Eléctrica de España (REE). Some of the administrative violations identified are classified as “very serious.” As might be expected, REE denies any wrongdoing and points out that, as early as 2023, it had drawn attention to the lack of tools at its disposal to balance voltage surges on the grid. Regardless of who is responsible, the Spanish power grid’s sensitivity to voltage fluctuations requires technical and economic adjustments to reduce the risk that such a blackout could happen again. And other countries are drawing the same lessons from this.
Vulnerability of Power Systems
We know that climate change is caused by the increase in greenhouse gas (GHG) stored in the atmosphere. By replacing carbon-based energy sources with (green) electricity, EU leaders aim to reduce GHG emissions over the coming decades. But emissions are flows, and unless we expect miracles from ocean absorption, biomass sequestration, and the reinjection of CO2 into the ground to reduce net flows, given the irresponsible policies pursued by certain developed countries (notably the U.S.) and the energy appetite of developing countries, the stock will continue to grow, and with it, climate disruption.
Yet electrical systems—power plants and grids—are vulnerable to storms, droughts, landslides, rising sea levels, and dark doldrums, the frequency and intensity of which increase with the GHGs stored above our heads. We are therefore faced with a dilemma: by increasing the share of renewable energy in our electricity mix, we reduce our GHG emissions, but emissions outside our borders continue to rise, leaving our power systems at the mercy of inevitable climate disruption.
Thermal power plants as backup
While it is true that sailboats sail for free, propelled by the wind, they can only guarantee reaching their destination on time if they have a backup electric or thermal engine. When regularity constraints are imposed on equipment powered by irregular energy sources, additional costs are to be expected. This is, metaphorically speaking, the problem that RTE and the CRE are seeking to address in their deliberation of April 9, 2026.
Under Article L. 321-11 of the Energy Code, the public transmission system operator (RTE) is responsible for ensuring the availability and deployment of the reserves necessary for the operation of the grid. To this end, “it freely negotiates with producers, suppliers, and other market participants the contracts necessary for the performance of these tasks, in accordance with competitive, non-discriminatory, and transparent procedures, such as public consultations or the use of organized markets.”
In these operations, the degree of freedom for producers is limited since “Any producer whose facilities have a design capacity for frequency or voltage control (nuclear, hydroelectric, and thermal power plants) makes this capacity available to the public transmission system operator, in accordance with participation terms and rules for determining remuneration based on objective and non-discriminatory criteria, which are developed and published by the public transmission system operator.”
The French grid operator RTE anticipates an increase in high-voltage phenomena on its grid, for various reasons including the increased frequency of periods of high renewable energy production. To address this, it proposes technical improvements as well as changes to the calculation of remuneration for called-upon producers. For example, since the current remuneration is a two-part tariff, RTE suggests introducing an “availability premium” into the fixed portion of the tariff: a balancing entity that is more available than the average of entities in the same sector over the past 10 years would be remunerated more than under current rules, and conversely for those that are less available than historical averages. It also suggests indexing remuneration to the consumer price index and increasing penalties in the event of a control entity’s failure.
The costs of grid stability are added to the maintenance costs of lines and transformers (see, for example, the N-1 rule, which stipulates that the grid must be capable of withstanding the loss of a component without affecting the end consumer) and are passed on to consumers via the TURPE (public transmission system access tariff). This is the price to pay for minimizing the risk of failure as much as possible, without, of course, being able to eliminate it entirely. To paraphrase the Spanish journalist José Luis Roig, it is not very useful to reinforce the front door if you leave the windows open.
Photo: Thomas Kelley Unsplash
