My explanation regarding the energy system failure in Spain has been picked up abroad, down to the smallest technical detail, and translated into English.
Although I wasn’t credited, I’m truly glad that people are now properly informed and that the public has access to a complete and rigorous understanding of the situation.
Thank you sincerely—and greetings to the audience in the United States!
I’m happy to offer a few simple explanations for people in Spain and beyond.
Such issues can happen when energy from synchronized sources (thermal, hydro, or nuclear power plants) drops significantly.
At that point, the power system becomes unstable because it lacks sufficient "inertia" – the ability to resist sudden frequency changes.
And when synchronized power is greatly reduced, the total energy volume in the system is lower too. If large fluctuations occur from solar or wind sources – which can easily happen due to increasing atmospheric instability and dense cloud cover – the system can reach a critical state.
If these renewable sources are not part of the new grid-forming generation (which can support and stabilize the network), the risk of sudden shutdowns or blackouts increases.
👉This is also a warning for Romania, where many conventional power plants have already been dismantled.👈
What happened in Spain yesterday? On April 28, 2025, Spain witnessed a major energy event: a nationwide blackout.
What was the cause? A massive overload of the electrical grid due to a huge spike in solar production. At around 11:00 AM, Spain’s solar power production reached a record peak of over 20 GW – a huge amount, rapidly injected into the grid in a very short period of time.
Normally, the electrical grid maintains a fine balance between production and consumption, in order to keep the frequency constant at 50 Hz. But today, the solar peak seriously disrupted this balance.
How did the collapse occur?
1. Solar energy flood:
Solar panels delivered a huge excess of current, dramatically reducing the need for energy from conventional power plants (gas, hydro, nuclear).
-Conventional power plants (especially gas and hydro) are equipped with turbines that rotate synchronously with the grid at 50 Hz.
-When energy demand drops suddenly (because solar energy covers all consumption), these turbines cannot slow down instantly.
-On the contrary: being still mechanically driven by engines or the flow of water, they begin to accelerate spontaneously.
3. Frequency increase:
-This acceleration leads to an increase in the grid frequency above 50 Hz.
-From a small imbalance, the frequency began to climb towards 50.5 Hz, 51 Hz or even more.
4. Confirmation of the phenomenon:
Further analyses showed that immediately after the solar peak, the energy injected into the grid by gas and hydro turbines increased sharply. This behavior confirms the theory of turbine acceleration and frequency increase:
-the turbines, having accumulated mechanical energy and sensing a decrease in load, injected even more energy into the grid, which amplified the imbalance and accelerated the collapse.
5. Activation of protections:
The electrical grid has automatic systems that protect equipment. If the frequency goes outside the safe range (usually 49.5–50.5 Hz), automatic disconnections begin:
-power plants are shut down,
-sections of the grid are cut,
-entire areas are isolated to prevent catastrophic damage.
6. Generalized collapse:
Because the system was unable to compensate for the surplus energy quickly enough, protections were triggered in a cascade, leading to the collapse of the electricity supply in almost all of Spain, Portugal and the south of France.
Why was the system unable to control the frequency?
Although modern grids have:
-Smart inverters (which can regulate the current),
-Fast Frequency Response batteries,
-Automatic generation reduction systems (AGC),
-their capacity was not enough to handle:
-the huge size of the solar peak (20 GW is enormous),
-the speed with which the surplus energy entered the grid,
-the lack of real mechanical inertia (which renewables do not offer).
Simply put:
Electronics can regulate the frequency in small and slow variations. But in a brutal energy shock, like today, only the mechanical mass of the turbines can stabilize the grid, and this has been overcome.
Spain already has a high percentage of renewable energy, which, paradoxically, makes the grid more fragile if there are not enough:
-high-capacity hydro pumps,
-fast export lines to France or other countries.
These are problems that we have publicly anticipated, including for Romania, that very violent photo and wind fluctuations can strongly disrupt the grid of conventional sources that have a different rhythm, a different inertia!!!! It is a fragile balance that can be especially supported with huge batteries or high-capacity export lines! Let's learn from such huge problems!!!
