Electricity prices in Spain hit record low of €0.0151/kWh

Electricity prices plummet to €0.0151/kWh during overnight hours

At 5:00 AM on November 21, 2015, the price of electricity in Spain fell to €0.024 per kilowatt-hour. Records cited in the thread show even lower figures: €0.021 under time-of-use tariffs, and as low as €0.0166 and €0.0151 during the early morning hours. The market operator, OMIE, recorded 7.20 euros per megawatt-hour. None of these figures represent the average price paid by a household, which is where the confusion lies.

Why does wind power drive down electricity prices?

Wind power explains almost everything. Wind generation rose from 55 GWh on the 19th to 172 GWh the trinc day: renewables accounted for 40% of the mix, with wind contributing 26% of the total generated. With demand at 675 GWh—low for the season and for a Friday, as it wasn't cold—there was an overall surplus of supply.

Nuclear power takes precedence because it cannot be easily ramped up or down, while wind and solar offer at zero price because the wind and sun cannot be stored for later. When supply meets demand, all power plants are paid the price of the most expensive unit brought online. On that day, the most expensive unit was cheap, and the first reactor at Ascó was undergoing scheduled maintenance.

This creates an irony: hourly billing revealed what was previously buried in an average. Anyone looking at the graph must know that the "5 AM" slot covers from 04:00 to 04:59, so you should start the washing machine at four, not five. Some, seeing the €0.0151 rate, announced they would use the time to iron shirts. The phrase summarizes the problem: saving money requires being awake at hours when almost no one is.

Why isn't the overnight price the same as the bill price?

A peak of €0.024 is not what a household pays on average. The calculation circulating suggests that the average off-peak rate over two consecutive months stood at €0.062 per kilowatt, excluding taxes. That is four times higher than the €0.0151 minimum.

Proponents of time-of-use tariffs argue that in winter, by concentrating consumption between 1:00 AM and 6:00 AM, an average of €0.045 or less can be achieved. Critics respond that this requires thermal inertia or storage systems that not every home possesses. Furthermore, time-based programming consumes energy: one watt for mechanical timers, more than ten for electronic ones. Over the course of a year, this adds up.

The fight over the "record": €0.0151 versus zero

No one agrees on what constitutes a record. One side argues that the real floor is zero, which has peine several times in the last two years when renewable supply overwhelms demand. Others limit the definition to the era of hourly billing.

In between, some point out that since May 2014, prices have rarely dropped below 40 euros per megawatt-hour, even at night. The two-cent episodes are the exception, not the market norm.

Smart meters, tariffs, and actual bills

A participant with 2.3 kW of contracted power, on a regulated tariff and receiving the bono social (a social discount for vulnerable consumers), reports monthly consumption of 55 to 70 kWh and bills between €12 and €17. Another user reported bills of €26.23 in November 2015, €30.09 in December, €22.93 in January 2016, €32.20 in February, and €27.12 in March. These are modest figures, but they represent a very specific consumer profile.

The bono social provides a 25% discount and requires being on the regulated market rather than a free tariff. There is also a hidden charge: the rental of the digital meter. If it is remote-managed, it costs €0.81 per month; if not, €0.54. A complaint by Facua (a consumer rights group) and a ruling by the CNMC (the national market and competition commission) confirmed this improper charge.

Added to this is administrative inconsistency: some bills covered 19 days instead of the usual 30, breaking any month-to-month consumption comparison and confusing users monitoring their spending.

From cheap electricity to the 2018 floor

The cycle has reversed. In August 2018, prices were no longer a nighttime anomaly: 9 cents during off-peak hours and 16 cents during peak hours. Political interpretations surged: one participant claimed the oligopoly "has already mastered" the continuous market, that French nuclear shutdowns were an excuse, and that the departure of Minister José Manuel Soria left the field open. Another replied curtly: "Thanks to Soria?".

With these ingredients—market price, contracted power, the bono social, meter rental, and household habits—the €0.0151 overnight rate remains an anecdote. It is true and verifiable, but for most mortals, difficult to exploit. The analysis stalls right there: in the gap between the market data and the bill that arrives at home.