Price of electricity today, October 21: the most expensive hour will be from 20:00 to 21:00 and the cheapest from 15:00 to 16:00

The setting of electricity prices in the Spanish wholesale market is regulated by European regulations, Spanish legislation, and operating rules approved by the CNMC. There is no provision establishing a specific price: the rules determine how purchase and sale offers are matched and how the resulting price is obtained. The most direct reference to the marginal nature of the day-ahead market appears in article 10.7 of CNMC Circular 3/2019.

1. The European framework

• Regulation (EU) 2019/943, of June 5, on the internal electricity market. It is the central European reference, directly applicable in Spain. It establishes that wholesale prices must be formed through the interaction of supply and demand and provides harmonized technical limits for market operation. See the text of the regulation.
• Regulation (EU) 2015/1222, of July 24. Establishes the guideline on capacity allocation and congestion management. It regulates the coupling of the European day-ahead and intraday markets: the matching considers offers and available capacity on interconnections. Therefore, the Spanish price is not determined in isolation.
• Regulation (EU) 2017/2195, of November 23. Establishes the guideline on electricity balancing. It is relevant for markets that correct imbalances between generation and consumption, different from the day-ahead auction.

2. Basic Spanish legislation

The Electricity Sector Law 24/2013, of December 26, shapes the production market and the functions of its operators. Its articles 28 and 29 frame the economic and technical management and entrust the market operator with managing purchase and sale offers in the day-ahead and intraday markets.

The Royal Decree 2019/1997, of December 26, which organizes and regulates the electricity production market, constitutes its basic regulatory development. It regulates market organization and recognizes the market operator as the central counterparty for purchases and sales in the day-ahead market.

3. The rule specifying the marginal price

The CNMC Circular 3/2019, of November 20, establishes methodologies for the wholesale market and system operation. Its article 10.7 states that offers scheduled in the day-ahead coupling will be settled "at the marginal price resulting from the matching of offers" for the corresponding period and zone.

Simply put, sale offers are ordered by price and matched with purchase offers; the marginal offer needed to cover demand determines the price of matched transactions. Interconnection capacity and offer conditions also play a role. This mechanism should not be confused with continuous intraday trading, where transactions have their own transaction price.

4. Operational rules and their updates

The details lie in the operating rules approved by the CNMC and applied by OMIE. Notable are the Resolution of May 23, 2024, on European intraday auctions, and the Resolution of February 28, 2025, on quarter-hourly negotiation and new offers. In August 2026, another modification was approved to introduce 96 continuous intraday rounds, as reported by Demócrata.

As an exceptional precedent, the Royal Decree-law 10/2022 created the Iberian cost adjustment mechanism. The Royal Decree-law 3/2023 extended its application until December 31, 2023: it is not the current ordinary regime. Finally, the wholesale price does not equate to the bill, which includes other costs, tolls, charges, and taxes.

The CNMC regulates and supervises the functioning of the electricity sector to ensure competition, transparency, and non-discriminatory access to networks, benefiting consumers and companies. It also investigates breaches and imposes sanctions within its powers. It does not direct energy policy nor operate the electrical system daily.

Its main framework is Law 3/2013, especially article 7, along with Law 24/2013 of the Electricity Sector and European regulations. Its competencies are grouped in the following areas.

1. Economic regulation of networks

The CNMC approves, through circulars and resolutions, methodologies on economic aspects of regulated activities. Its functions include:

• Establishing the methodology for transport and distribution tolls, which remunerate network use.
• Regulating remuneration methodologies for network installations and activities within legally attributed competencies.
• Requiring information from companies to verify costs, investments, and compliance with obligations.

These powers do not equate to setting all bill components nor the price of offers in the free market.

2. Access and connection to networks

It establishes methodologies and conditions for accessing and connecting to transport and distribution networks. This includes the content of requests and permits, economic criteria, capacity evaluation, reasons for denial, minimum contract content, and transparency obligations.

The attribution is expressly stated in article 33.11 of the Electricity Sector Law, reproduced in the resolution on demand access. It also approves technical specifications so managers calculate capacity with homogeneous criteria.

3. Market supervision and competition

It monitors wholesale and retail markets: price formation, transparency, agent behavior, and separation between regulated and competitive activities. It investigates restrictive agreements and abuses of dominant position, as well as possible energy market manipulations.

In this last area, it applies the REMIT Regulation, on integrity and transparency of wholesale markets, in coordination with ACER, the European agency for regulator cooperation. The institutional explanation of its functions confirms this monitoring role.

4. System operation and interconnections

It approves methodologies, conditions, and certain operating procedures, including balancing services — which adjust generation and consumption — and non-frequency services, such as voltage control. It also intervenes in access rules to international interconnections, capacity allocation, and congestion management.

It supervises Red Eléctrica and may require information from it, but does not replace the system operator. An example of this power is the resolution on voltage stabilization.

5. Consumer protection

It supervises supplier changes, contractual information, commercial practices, and obligations of distributors and suppliers. It publishes guidance and comparison tools and ensures protection measures are effective.

This supervision should be distinguished from individual claims: certain disputes about contracts or bills correspond to competent regional bodies, consumer mechanisms, or courts.

6. Inspection, sanction, and limits

It may require information, investigate, and impose sanctions for energy and competition infringements within its powers, with administrative procedure guarantees. The Government retains energy policy and general planning; autonomous communities maintain their authorization, inspection, and consumer competencies. Therefore, the CNMC is a regulator and supervisor, not the sole authority of the sector.

To change your electricity tariff in Spain you need to authorize the new contract, identify the supply point, and provide your data. You do not have to change distributor or disconnect the electricity. Additional requirements depend on whether you only change price or supplier, modify power, or want to access the regulated market.

1. Identification and consent

For a domestic supply, the company usually requests the following documentation, which you can prepare with a recent bill:

• ID card or NIE of the holder and their contact details.
• Property address and CUPS, the code identifying the supply point.
• Contracted power and bank details for direct debit.
• When applicable, proof of ownership or authorization to act on behalf of the holder.

The supplier must verify identity and keep proof of consent: having your data is not enough. If the contract is not in your name, it is advisable to process ownership or prove representation. The CNMC has reminded these obligations, as reported by Demócrata on electricity contracting.

2. Check conditions before accepting

Before contracting, review the energy and power price, duration, renewals, discounts, and additional services. The supplier must inform you clearly and provide a price comparison when applicable, as explained by the Ministry for Ecological Transition.

Changing supplier is free, but that does not eliminate any obligation from the previous contract. For households and small businesses with power below 15 kW, the rule is to be able to terminate without penalty. The exception affects fixed-price free market contracts before their first annual renewal: the maximum penalty is 5% of the estimated pending energy supply, not the entire future bill. Also check if maintenance is canceled separately.

3. Processing and timeframe

If you change company, the new supplier manages the procedure with the distributor. The latter remains because it depends on the area. Do not request disconnection of the supply point: changing company should not leave you without electricity.

The maximum period is 10 business days from contract formalization, extendable exceptionally by five business days when complex field actions are necessary. This is detailed by the Andalusian Government. If you only change offer within your company, confirm the application date in writing.

4. Power and meter

Changing price or supplier does not require modifying power or replacing the meter. Nor is having remote management a general requirement to change company, although certain modalities may require specific measurement functions.

If you also increase power, regulated rights and technical installation documentation may be required, especially if you exceed its admissible capacity. Reducing it may also generate an action cost. These are operations distinct from supplier change; consult the CNMC guidance for consumers.

5. Regulated market and consumer protection

To contract the PVPC, the regulated tariff, you must go to a reference supplier and meet their access conditions. If you receive the social bonus, moving to the free market means losing it: the new company must inform you and obtain your express and written consent.

For contracts via internet, phone, or off-premises, you generally have 14 calendar days to withdraw. Keep the offer, contract, and change confirmation, and review the first bill to verify prices, services, and effective date.