It may look like a ‘technical’ change, but it actually marks a turning point in understanding (and optimising) energy in businesses, industry and self-consumption.

What exactly has changed?

Until now, the wholesale market (the ‘pool’) cleared one price for each hour of the day. Since the change:

• Each hour is divided into 4 slots: 00:00–00:15, 00:15–00:30, 00:30–00:45, 00:45–01:00, etc.
• So we move to 96 price periods a day.
• OMIE (the Iberian electricity market operator) already reflects this with periods such as H1Q1 (first quarter of the first hour), etc.  

And note the date: the ‘historic’ market clearing for the switch took place on 30 September 2025, already producing the 96 prices for energy delivered on 1 October.  

Why is this change happening? (the underlying reason)

The short answer: because the electricity system no longer behaves ‘by the hour’.

With renewables (solar and wind) carrying ever more weight, generation can vary considerably within a single hour. With prices every 15 minutes:

1. The price better reflects what it costs to produce electricity at each moment, matching supply and demand more precisely.  
2. Europe harmonises the electricity market through the EU single day-ahead coupling (SDAC), so that all countries ‘play’ with the same time unit.  
3. It is in step with the system’s shift towards finer balancing processes: Spain has also been adapting its imbalance settlement to 15 minutes, which is key for a more renewable and variable system.  

Who does it affect?

It depends on your type of contract and how your consumption is metered:

• Companies on a pool-indexed tariff: the ‘reference’ price becomes more granular (and therefore more opportunities to optimise appear… along with more intra-hour variability).
• Industry and consumers with a detailed load profile: this change has much more impact, because the real cost can differ within the same hour.
• Households: in practice, the immediate impact may be limited for many domestic users, depending on how the measure is applied and the effective granularity of meter reading/billing.  

What opportunities does it open up for a business?

This is where it gets interesting. With prices every 15 minutes, saving is no longer about ‘changing the hour’ but about ‘moving specific processes’:

• Shift flexible loads (HVAC, pumping, charging, staged furnaces, compressors, etc.) to cheaper quarter-hours.
• Detect micro-peaks: sometimes the expensive peak no longer lasts 1 hour… it lasts 15 minutes (and can be avoided).
• Optimise self-consumption and batteries: with finer time detail, you can better fine-tune when to use the grid, when to draw on the battery and when to charge it.
• Better analysis of €/unit produced (€/tonne, €/part, €/batch): if your production and energy data have fine resolution, the KPI improves enormously.

How does Powercloud approach it?

At Powercloud, this change translates into something very concrete: more precision to turn energy into euros, and euros into decisions.

Some practical ideas (very ‘shop-floor’):

• Energy cost per quarter-hour by line/process/site.
• Alerts if your consumption falls right in the most expensive quarter-hours of the day.
• Weekly comparisons: ‘my 10 most expensive quarter-hours’ vs ‘my 10 cheapest quarter-hours’.
• Business KPIs (€/t, €/unit) with better traceability.

Wrapping up

The quarter-hourly market is not a passing fad: it is the natural consequence of a more dynamic, more renewable and more European electricity system. And for businesses, it is a clear opportunity: if you can measure, you can understand; if you can understand, you can optimise.

If you like, in a future post we can bring this down to earth with a real example (e.g. a plant with compressors + self-consumption) and show which decisions emerge when you go from 24 to 96 prices a day.

La entrada Goodbye to ‘hourly’ prices: the electricity market now runs in quarter-hours (15 min) se publicó primero en Powercloud | Energy monitoring and management.