Electricity price today, November 4: the most expensive hour will be from 18:00 to 19:00 and the cheapest from 14:00 to 15:00

The daily price of electricity in the wholesale market (“pool”) in Spain is determined, in a simplified way, by the intersection between the sale offers from generators and hourly demand forecasts, within a European marginal market. This basic mechanism is mainly influenced by fuel costs, CO₂ prices, renewable availability, grid conditions, and regulatory rules for matching and price limits.

In practice, the process works as follows:

• European coupled day-ahead market: Spain is part of the Iberian market (MIBEL, together with Portugal) and, in turn, the European coupled day-ahead market. For each hour of the next day, retailers and large consumers submit demand forecasts and generators submit sale offers indicating how much energy they are willing to produce and at what minimum price.
• Ordering offers by cost: the market operator (OMIE) orders generation offers from lowest to highest price. Technologies with very low variable costs usually enter first (nuclear, wind, solar, run-of-river hydro), then manageable reservoir hydro, and finally the most expensive plants (mainly gas combined cycles and, to a lesser extent, fuel oil in isolated systems).
• Matching point: offers are accepted starting from the cheapest until the forecasted demand for each hour is covered. The last offer needed to satisfy all demand sets the marginal price for that hour. That same price is paid to all technologies matched in that hour, regardless of their individual lower offer.

Based on this scheme, the key factors determining that marginal price are:

• Fossil fuel costs: the international price of natural gas (the main fuel for combined cycles) is decisive when these plants enter the matching as the marginal technology. If gas prices rise, combined cycles must offer higher prices to cover their costs, pushing up the hourly price when they are needed to meet demand.
• Price of CO₂ emission rights: plants emitting CO₂ (gas, coal where still existing, fuel oil) must acquire emission rights in the European market. The more expensive these rights are, the higher the variable cost of these plants and, again, the higher their offer and thus the marginal price in the hours they set the price.
• Availability of renewables and nuclear: wind, photovoltaic, some hydro, and nuclear have very low variable costs and offer at very low prices (often close to zero). When there is a lot of renewable and nuclear production available, they displace more expensive technologies, so demand is covered without (or with less) need for combined cycles, reducing the marginal price.
• Forecasted demand: extreme temperatures, economic activity, and consumption habits influence the demand profile. During peak hours with very high demand, more expensive generation usually needs to be activated, while during off-peak hours cheap technologies suffice. That is why prices differ greatly between, for example, a mild early morning and a hot summer afternoon.
• Availability and management of hydro: manageable hydro generation (reservoirs) can decide when to produce. Operators value stored water according to future price expectations, hydrology, and environmental restrictions. In dry periods or with low reservoirs, they tend to offer at higher prices and reserve water, which can raise the marginal price in several hours.
• Interconnections with other countries: interconnections with France and Portugal allow importing or exporting electricity. If the expected price in France is very high, it may be profitable to export from Spain, increasing the effective demand to be covered by the pool and thus the price. Conversely, importing cheap energy can reduce the Spanish price at certain hours.
• Technical constraints and grid congestions: system operation must respect physical grid limits. When there are congestions or restrictions, the operator may need to activate more expensive generation in certain zones or limit the use of very cheap plants, affecting the matching price in those hours.
• Market regulation: participation rules (maximum and minimum price limits, guarantee requirements, intraday products, balancing services, etc.) condition how agents offer. Regulatory changes — such as temporary caps on certain offers or exceptional mechanisms — can dampen or amplify the pass-through of gas and CO₂ costs to the pool price.

It is worth remembering that this daily marginal price in the wholesale market is only one component of the final bill: access tolls, regulated charges, capacity costs, taxes, and commercial margins are added to it. However, it is the main reference for contracts indexed to the market and for calculating the energy cost in many regulated and free supplies.

The National Commission on Markets and Competition (CNMC) supervises the electricity market to ensure its proper functioning, transparency, and effective competition, for the benefit of consumers. It combines economic regulation, monitoring, inspection, and sanctioning functions, but does not physically operate the system nor decide all energy policy.

Its main framework is Article 7 of Law 3/2013, establishing the CNMC, along with Law 24/2013 on the Electricity Sector, and applicable European regulations.

1. Market and participant monitoring

The CNMC supervises the wholesale market, where electricity is traded, and the retail market, where retailers contract with consumers. It examines prices, offers, contracting, and agent behavior, and controls obligations of producers, retailers, transporters, and distributors.

It also monitors the functional and accounting unbundling of integrated companies to prevent regulated activities from unduly favoring other companies in the same group. In application of the European REMIT Regulation, it supervises the integrity and transparency of wholesale electricity markets, including detecting possible manipulative behaviors, as explained in this institutional reference.

2. Networks, access, and system operation

It controls third-party access to networks, congestion management, and interconnection capacity allocation. It also supervises the system operator’s performance, connection and repair deadlines, and aspects related to supply quality and continuity.

The CNMC approves methodologies and access and connection conditions within its competence via circulars: content of requests and permits, capacity evaluation, denial reasons, economic conditions, and transparency obligations. This attribution is recorded in the resolution on access capacities. It also resolves certain network access conflicts and approves operation procedures in legally attributed matters.

3. Tolls and network remuneration

It establishes methodologies and values of transport and distribution tolls, which finance network use, as well as remuneration methodologies for these activities. It also performs settlement and monitoring functions of regulated revenues and costs.

A distinction must be made between tolls and charges: the former correspond to the CNMC; charges, intended for other regulated system costs, are determined at the governmental level. Therefore, the CNMC does not set all bill components by itself.

4. Consumers, information, and inspection

It supervises price transparency and contractual conditions, billing, retailer switching, and compliance with consumer protection measures. It also monitors complaint handling, although it does not resolve every individual dispute: depending on the matter, regional authorities, consumer bodies, or courts may intervene.

To exercise these functions, it may require information, issue informative circulars, and inspect sector subjects, checking contracts, measurements, invoices, and compliance with regulatory obligations.

5. Sanctions and competition defense

It can investigate and impose sanctions for electricity infractions attributed by law, respecting procedures and competence limits. Separately, it acts as competition authority against restrictive agreements, market sharing, or abuse of dominant position, and analyzes business concentrations when appropriate.

In short, the CNMC regulates and controls; Red Eléctrica performs technical operation, and the Government retains energy policy and other administrative powers. This separation avoids confusing system supervision with daily management.

In Spain, being authorized to retail energy is not enough to offer regulated tariffs. If referring to electricity and natural gas, the company also needs the specific status of reference retailer to offer the regulated electricity tariff (PVPC) or last resort retailer to supply gas under the TUR. These are two distinct regimes: access requirements for one should not be automatically transferred to the other.

1. General authorization to retail

The company must meet the legal, technical, and economic conditions required to carry out retailing: formalize the corresponding start notification and responsible declaration, have operational capacity, and comply with energy acquisition, guarantees, contracting, and system operator relations obligations.

In electricity, the framework includes Law 24/2013 and Royal Decree 88/2026, regulating supply, retailing, and aggregation. In gas, relevant are Law 34/1998 and Royal Decree 1434/2002. This general authorization does not by itself grant access to the regulated market.

2. Electricity: status as reference retailer

Royal Decree 216/2014 establishes the specific regime. For the voluntary application route, identified requirements include:

• Experience: having continuously carried out retailing during the previous three years.
• Size: proving an average minimum of 25,000 customers during the previous twelve months.
• Solvency: having a minimum share capital of 500,000 euros.
• Absence of impediments: not having been disqualified during the previous three years nor incurring prohibitions related to certain serious or very serious final sanctions. There are also restrictions linked to the corporate group and forced customer transfers.

There is also a mandatory route for corporate groups that have supplied more than 100,000 customers on average during the last twelve months; the specific threshold for Ceuta and Melilla is 25,000. These thresholds should not be confused with those required to voluntarily request designation.

Once recognized, the retailer must apply the PVPC methodology and supply those entitled. Generally, these are individuals or microenterprises with voltage not exceeding 1 kV and contracted power equal to or less than 10 kW in each time period.

3. Gas: designation as last resort retailer

To offer TUR, the company needs the specific designation as last resort retailer, in addition to meeting general gas retailing conditions. Royal Decree 104/2010 regulates this supply; electrical requirements of capital, seniority, and portfolio do not automatically apply to gas.

The company must serve consumers entitled to TUR and bill according to the regulated regime. Its methodology is set out in Order ITC/1660/2009, with prices published by administrative resolutions.

4. Ongoing obligations

Access to the regulated regime implies ongoing obligations: transparent contractual information, correct billing, customer service and complaints, data protection, and respect for guarantees against supply suspension.

Additionally, reference electricity retailers must keep separate accounts for this activity, apply the social bonus to beneficiaries, and avoid confusion with free market brands. In short, three elements must be separately verified: general authorization, specific designation, and ongoing compliance; having only the first does not legally allow offering PVPC or TUR.