{"content_id":"yu6ko1em4n","slug":"spain-portugal-new-electricity-interconnection","locale":"en","schema_type":"Report","category":"report","category_name":"Report","title":"Impact of the New Spain-Portugal Interconnector on the Iberian Power Market","summary":"The interconnector between Galicia, Spain, and northern Portugal, which began operating in July 2026, increased the two countries' maximum power exchange capacity to about 4.2GW. It provides a stronger foundation for reducing renewable energy curtailment and price gaps, but its actual impact will depend on domestic transmission grids and interconnection capacity toward France.","author":{"name":"Injoys Editorial Team","url":"https://injoys.com/ko/about"},"key_points":["The new interconnector increased power exchange capacity between Spain and Portugal by about 1GW, bringing the maximum to approximately 4.2GW.","Power on the AC interconnector flows in both directions depending on market outcomes and grid conditions, and the actual available capacity in each direction may vary hourly.","When there is demand and available transmission capacity across the border, surplus wind and solar power can be used in a broader market.","The interconnector can mitigate wholesale price gaps and supply risks, but it does not guarantee lower final electricity bills for consumers.","Resolving the Iberian Peninsula's energy island problem will require expanding not only the Spain-Portugal interconnection but also interconnections toward France and each country's domestic power grid."],"content_markdown":"A new power interconnector linking Galicia in Spain with northern Portugal began operations on July 2, 2026. According to the European Commission, the facility added approximately 1GW of electricity exchange capacity between the two countries, raising the maximum to about 4.2GW.\n\nThe significance of this project goes beyond simply adding another transmission line across the border. When wind and solar generation exceeds regional demand, electricity can be sent to a broader market, while regions experiencing generation shortages or equipment failures have greater scope to receive power from the grid on the other side. However, the announced maximum capacity may differ from the capacity actually available to the market.\n\n## Key Figures and Structure of the New Interconnector\n\n| Item | Details | Points to Note When Interpreting |\n|---|---|---|\n| Operational date | July 2, 2026 | The date of the completion or opening announcement and the point at which all operating conditions apply may differ depending on operational procedures. |\n| Connected regions | Galicia in Spain and northern Portugal | The interconnector also uses substations within both countries and the existing 400kV-class transmission network. |\n| Additional exchange capacity | Approximately 1GW | This does not mean that a new 1GW power plant has been built, but that the limit on the amount of electricity that can be transferred across the border has increased. |\n| Maximum exchange capacity after expansion | Approximately 4.2GW | Real-time available capacity may be lower due to outages, maintenance, temperature, grid stability criteria, and internal congestion. |\n| Power flow | Bidirectional | This is not a dedicated line that carries electricity only from Spain to Portugal; the direction changes according to market and grid conditions. |\n\nHere, MW or GW represents the amount of power that can be transmitted at a specific moment. The amount of electricity actually transferred over a given period is measured in MWh or GWh. Therefore, the fact that the maximum exchange capacity is 4.2GW alone does not indicate the annual volume of electricity traded.\n\nThe term bidirectional also does not mean that the same 4.2GW is always available in both directions. The transmission system operators of the two countries separately calculate the capacity that can be offered to the market, taking into account the generation mix, demand, maintenance status, and grid safety criteria in each direction. As a result, the available capacity from Spain to Portugal may differ from that in the opposite direction.\n\n## How Surplus Wind and Solar Power Crosses the Border\n\nSpain and Portugal operate power systems with high shares of wind, solar, and hydroelectric generation. Because generation changes rapidly with the weather, there may simultaneously be periods when one region has surplus electricity and another region needs power.\n\nThe process through which surplus renewable energy is used generally works as follows.\n\n1. Power producers submit hourly generation volumes and prices to the Iberian electricity market.\n2. Market results are determined based on demand in Spain and Portugal, generation offers, and available cross-border capacity.\n3. Commercial exchange schedules are created from regions able to produce inexpensive electricity to relatively more expensive regions.\n4. Transmission system operators manage actual operations by checking voltage, frequency, line overloads, and safety criteria in the event of failures.\n5. If forecasting errors or unexpected failures occur, reserve capacity and real-time balancing resources are deployed.\n\nRenewable electricity does not travel to its destination through a separate physical route. In an alternating-current power grid, actual current is distributed across multiple lines according to electrical impedance and overall grid conditions. This is why cross-border transactions determined by the market may not fully match physical power flows.\n\n## Conditions for Reducing Grid Congestion and Curtailment\n\nCurtailment refers to measures that reduce the output of wind and solar facilities capable of generating electricity because of grid safety or supply-demand balancing requirements. The new interconnector can reduce the likelihood of curtailment by providing an additional route for sending surplus electricity across the border.\n\nHowever, the following conditions must also be met for this effect to materialize.\n\n- **There must be demand on the other side.** If both countries simultaneously produce excess renewable energy, there may be insufficient export destinations even when cross-border capacity remains available.\n- **The domestic grids of both countries must have spare capacity.** If domestic transmission lines between wind and solar farms and the cross-border connection point are congested, the new interconnector cannot be fully utilized.\n- **Storage and demand-response resources must operate.** Pumped-storage hydropower, batteries, industrial demand adjustment, and electric-vehicle charging help shift surplus electricity to other periods.\n- **Capacity must be made available to the market.** Transmission operators offer only the capacity remaining after accounting for maintenance and safety margins.\n- **The system must remain safe during failures.** Operating limits are set so that the loss of one critical facility does not lead to a widespread blackout.\n\nExpanding interconnection capacity is therefore not a sufficient condition for reducing curtailment, but one of several solutions. Domestic transmission networks, storage facilities, flexible generation sources, and demand response must also be expanded to increase renewable-energy hosting capacity reliably.\n\n## Impact on the Iberian Electricity Market and Wholesale Prices\n\nSpain and Portugal operate MIBEL, a joint wholesale market, but cross-border interconnection capacity is not always sufficient. When adequate exchange capacity is available, generators in the relatively less expensive region can serve demand more broadly across both countries, allowing prices to converge or become equal.\n\nConversely, the market becomes congested when the required volume of electricity exchange exceeds interconnection capacity. Prices in the two countries then separate, and prices may be higher on the side facing an electricity shortage. The new interconnector could reduce the frequency and duration of such price separation.\n\nFor example, when wind power is abundant in northwestern Spain and demand is high in Portugal, electricity transfers from Spain to Portugal may increase. In the evening, when hydropower conditions are favorable in Portugal and solar output declines in Spain, flow in the opposite direction may be economically advantageous.\n\nHowever, expanding interconnection capacity does not lower prices during every period. Prices may rise somewhat from previous levels in regions that export more electricity and may fall in importing regions. The main effects are to narrow the price gap between the two markets and enable lower-cost generation sources to be used across a broader area.\n\n## Consumer Electricity Rates and Security of Supply\n\n### Consumer Rates\n\nIf the interconnector mitigates wholesale price spikes and price differences between the two countries, it may also create downward pressure on retail rates. However, the final rates paid by households and businesses do not move in line with wholesale prices because they consist of the following components.\n\n- Wholesale electricity procurement costs\n- Transmission and distribution network charges and interconnection investment costs\n- Retail operators’ operating and risk-management costs\n- Taxes, levies, and policy costs\n- The method used to reflect prices in fixed-rate plans or long-term contracts\n\nIt therefore cannot be assumed that the new interconnector will necessarily lower consumer rates. The net effect must be assessed by considering the generation costs saved through congestion relief, the costs of constructing and operating the power network, and each country’s rate regulations.\n\n### Security of Supply\n\nThe interconnector increases the options for procuring power from the other side when one country experiences power plant failures, drought, extreme heat, or an unexpected increase in demand. It also broadens the scope for the two countries to share required reserve capacity.\n\nHowever, as interconnection increases, the risk that frequency disturbances or large-scale equipment failures in one region may spread to another must also be managed. This is why automatic protection systems, emergency power exchange procedures, joint training among transmission system operators, and real-time information sharing are necessary.\n\n## Interconnection with France and the Energy Island Problem\n\nThe Iberian Peninsula has long been described as an “energy island” because its power-grid connections with the center of continental Europe are relatively limited. Even if bottlenecks between Spain and Portugal are reduced, there will still be limits on sending surplus electricity from Iberia as a whole to other parts of Europe unless sufficient exchange capacity is available across the Pyrenees from Spain to France.\n\nThis structure creates the following problems.\n\n- Export destinations are limited when Spain and Portugal simultaneously generate large amounts of solar and wind power.\n- Price differences between France and the Iberian Peninsula may persist for extended periods.\n- In circumstances affecting all of Iberia, such as drought or a prolonged period of low wind speeds, capacity for imports from outside the region may be insufficient.\n- Congestion may recur if investment in renewable generation, green hydrogen, and electrified industries grows faster than domestic transmission networks and cross-border interconnections.\n\nNew interconnection projects toward France are a key task in integrating the Iberian market more deeply with the European electricity market. At the same time, domestic transmission networks in Galicia and northern Portugal must be reinforced, storage facilities expanded, and grid-stabilization resources secured.\n\n## Indicators for Assessing Future Effects\n\nThe performance of the new interconnector is difficult to evaluate based solely on its nominal capacity at completion. At a minimum, the following indicators must be monitored across multiple seasons.\n\n| Assessment Area | Indicators to Monitor | Significance |\n|---|---|---|\n| Utilization | Electricity flows by direction and time of day, utilization relative to available capacity | Shows how often the interconnector is actually used and in which direction. |\n| Market integration | Hours of price separation between Spain and Portugal, average price difference | Measures congestion relief and market-coupling effects. |\n| Renewable energy | Volume of wind and solar curtailment, hours of negative prices | Indicates whether the utilization of surplus generation has improved. |\n| Security of supply | Emergency import and export volumes, hours of supply shortages, reserve procurement costs | Shows improvements in crisis-response capabilities and reliability. |\n| Consumer impact | Wholesale prices, network charges, final retail rates | Identifies the net effect of market benefits and infrastructure costs. |\n| Grid operation | Planned and unplanned outages, congestion-management costs, redispatch costs | Reveals new bottlenecks or operational constraints. |\n\nIn particular, the maximum figure of 4.2GW must be distinguished from actual available capacity. Even if annual utilization is low, the interconnector may have significant grid value if it serves as insurance by preventing supply shortages during demand spikes or equipment failures. Conversely, even if utilization is high, continued internal bottlenecks and repeated curtailment in both countries would signal a need for additional investment.\n\n## Overall Assessment\n\nThe new Spain-Portugal interconnector is critical infrastructure that strengthens the physical foundation of MIBEL and enables renewable energy to be used across a broader region. The approximately 1GW of additional exchange capacity could reduce price differences, curtailment, and the risk of supply shortages in the two countries.\n\nHowever, the interconnector itself does not guarantee inexpensive electricity or unlimited renewable-energy hosting capacity. Its actual performance will depend on the capacity made available to the market, the domestic grids of both countries, storage and demand response, interconnection toward France, and consumer-rate systems. Over the long term, these elements must be assessed as part of a single, integrated European power-system challenge.","content_html":"\u003cp\u003eA new power interconnector linking Galicia in Spain with northern Portugal began operations on July 2, 2026. According to the European Commission, the facility added approximately 1GW of electricity exchange capacity between the two countries, raising the maximum to about 4.2GW.\u003c/p\u003e\n\u003cp\u003eThe significance of this project goes beyond simply adding another transmission line across the border. When wind and solar generation exceeds regional demand, electricity can be sent to a broader market, while regions experiencing generation shortages or equipment failures have greater scope to receive power from the grid on the other side. However, the announced maximum capacity may differ from the capacity actually available to the market.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#key-figures-and-structure-of-the-new-interconnector\" class=\"anchor\" id=\"key-figures-and-structure-of-the-new-interconnector\"\u003e\u003c/a\u003eKey Figures and Structure of the New Interconnector\u003c/h2\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eItem\u003c/th\u003e\n\u003cth\u003eDetails\u003c/th\u003e\n\u003cth\u003ePoints to Note When Interpreting\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Item\"\u003eOperational date\u003c/td\u003e\n\u003ctd data-label=\"Details\"\u003eJuly 2, 2026\u003c/td\u003e\n\u003ctd data-label=\"Points to Note When Interpreting\"\u003eThe date of the completion or opening announcement and the point at which all operating conditions apply may differ depending on operational procedures.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Item\"\u003eConnected regions\u003c/td\u003e\n\u003ctd data-label=\"Details\"\u003eGalicia in Spain and northern Portugal\u003c/td\u003e\n\u003ctd data-label=\"Points to Note When Interpreting\"\u003eThe interconnector also uses substations within both countries and the existing 400kV-class transmission network.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Item\"\u003eAdditional exchange capacity\u003c/td\u003e\n\u003ctd data-label=\"Details\"\u003eApproximately 1GW\u003c/td\u003e\n\u003ctd data-label=\"Points to Note When Interpreting\"\u003eThis does not mean that a new 1GW power plant has been built, but that the limit on the amount of electricity that can be transferred across the border has increased.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Item\"\u003eMaximum exchange capacity after expansion\u003c/td\u003e\n\u003ctd data-label=\"Details\"\u003eApproximately 4.2GW\u003c/td\u003e\n\u003ctd data-label=\"Points to Note When Interpreting\"\u003eReal-time available capacity may be lower due to outages, maintenance, temperature, grid stability criteria, and internal congestion.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Item\"\u003ePower flow\u003c/td\u003e\n\u003ctd data-label=\"Details\"\u003eBidirectional\u003c/td\u003e\n\u003ctd data-label=\"Points to Note When Interpreting\"\u003eThis is not a dedicated line that carries electricity only from Spain to Portugal; the direction changes according to market and grid conditions.\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eHere, MW or GW represents the amount of power that can be transmitted at a specific moment. The amount of electricity actually transferred over a given period is measured in MWh or GWh. Therefore, the fact that the maximum exchange capacity is 4.2GW alone does not indicate the annual volume of electricity traded.\u003c/p\u003e\n\u003cp\u003eThe term bidirectional also does not mean that the same 4.2GW is always available in both directions. The transmission system operators of the two countries separately calculate the capacity that can be offered to the market, taking into account the generation mix, demand, maintenance status, and grid safety criteria in each direction. As a result, the available capacity from Spain to Portugal may differ from that in the opposite direction.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#how-surplus-wind-and-solar-power-crosses-the-border\" class=\"anchor\" id=\"how-surplus-wind-and-solar-power-crosses-the-border\"\u003e\u003c/a\u003eHow Surplus Wind and Solar Power Crosses the Border\u003c/h2\u003e\n\u003cp\u003eSpain and Portugal operate power systems with high shares of wind, solar, and hydroelectric generation. Because generation changes rapidly with the weather, there may simultaneously be periods when one region has surplus electricity and another region needs power.\u003c/p\u003e\n\u003cp\u003eThe process through which surplus renewable energy is used generally works as follows.\u003c/p\u003e\n\u003col\u003e\n\u003cli\u003ePower producers submit hourly generation volumes and prices to the Iberian electricity market.\u003c/li\u003e\n\u003cli\u003eMarket results are determined based on demand in Spain and Portugal, generation offers, and available cross-border capacity.\u003c/li\u003e\n\u003cli\u003eCommercial exchange schedules are created from regions able to produce inexpensive electricity to relatively more expensive regions.\u003c/li\u003e\n\u003cli\u003eTransmission system operators manage actual operations by checking voltage, frequency, line overloads, and safety criteria in the event of failures.\u003c/li\u003e\n\u003cli\u003eIf forecasting errors or unexpected failures occur, reserve capacity and real-time balancing resources are deployed.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eRenewable electricity does not travel to its destination through a separate physical route. In an alternating-current power grid, actual current is distributed across multiple lines according to electrical impedance and overall grid conditions. This is why cross-border transactions determined by the market may not fully match physical power flows.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#conditions-for-reducing-grid-congestion-and-curtailment\" class=\"anchor\" id=\"conditions-for-reducing-grid-congestion-and-curtailment\"\u003e\u003c/a\u003eConditions for Reducing Grid Congestion and Curtailment\u003c/h2\u003e\n\u003cp\u003eCurtailment refers to measures that reduce the output of wind and solar facilities capable of generating electricity because of grid safety or supply-demand balancing requirements. The new interconnector can reduce the likelihood of curtailment by providing an additional route for sending surplus electricity across the border.\u003c/p\u003e\n\u003cp\u003eHowever, the following conditions must also be met for this effect to materialize.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThere must be demand on the other side.\u003c/strong\u003e If both countries simultaneously produce excess renewable energy, there may be insufficient export destinations even when cross-border capacity remains available.\u003c/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe domestic grids of both countries must have spare capacity.\u003c/strong\u003e If domestic transmission lines between wind and solar farms and the cross-border connection point are congested, the new interconnector cannot be fully utilized.\u003c/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStorage and demand-response resources must operate.\u003c/strong\u003e Pumped-storage hydropower, batteries, industrial demand adjustment, and electric-vehicle charging help shift surplus electricity to other periods.\u003c/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCapacity must be made available to the market.\u003c/strong\u003e Transmission operators offer only the capacity remaining after accounting for maintenance and safety margins.\u003c/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe system must remain safe during failures.\u003c/strong\u003e Operating limits are set so that the loss of one critical facility does not lead to a widespread blackout.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eExpanding interconnection capacity is therefore not a sufficient condition for reducing curtailment, but one of several solutions. Domestic transmission networks, storage facilities, flexible generation sources, and demand response must also be expanded to increase renewable-energy hosting capacity reliably.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#impact-on-the-iberian-electricity-market-and-wholesale-prices\" class=\"anchor\" id=\"impact-on-the-iberian-electricity-market-and-wholesale-prices\"\u003e\u003c/a\u003eImpact on the Iberian Electricity Market and Wholesale Prices\u003c/h2\u003e\n\u003cp\u003eSpain and Portugal operate MIBEL, a joint wholesale market, but cross-border interconnection capacity is not always sufficient. When adequate exchange capacity is available, generators in the relatively less expensive region can serve demand more broadly across both countries, allowing prices to converge or become equal.\u003c/p\u003e\n\u003cp\u003eConversely, the market becomes congested when the required volume of electricity exchange exceeds interconnection capacity. Prices in the two countries then separate, and prices may be higher on the side facing an electricity shortage. The new interconnector could reduce the frequency and duration of such price separation.\u003c/p\u003e\n\u003cp\u003eFor example, when wind power is abundant in northwestern Spain and demand is high in Portugal, electricity transfers from Spain to Portugal may increase. In the evening, when hydropower conditions are favorable in Portugal and solar output declines in Spain, flow in the opposite direction may be economically advantageous.\u003c/p\u003e\n\u003cp\u003eHowever, expanding interconnection capacity does not lower prices during every period. Prices may rise somewhat from previous levels in regions that export more electricity and may fall in importing regions. The main effects are to narrow the price gap between the two markets and enable lower-cost generation sources to be used across a broader area.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#consumer-electricity-rates-and-security-of-supply\" class=\"anchor\" id=\"consumer-electricity-rates-and-security-of-supply\"\u003e\u003c/a\u003eConsumer Electricity Rates and Security of Supply\u003c/h2\u003e\n\u003ch3\u003e\n\u003ca href=\"#consumer-rates\" class=\"anchor\" id=\"consumer-rates\"\u003e\u003c/a\u003eConsumer Rates\u003c/h3\u003e\n\u003cp\u003eIf the interconnector mitigates wholesale price spikes and price differences between the two countries, it may also create downward pressure on retail rates. However, the final rates paid by households and businesses do not move in line with wholesale prices because they consist of the following components.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eWholesale electricity procurement costs\u003c/li\u003e\n\u003cli\u003eTransmission and distribution network charges and interconnection investment costs\u003c/li\u003e\n\u003cli\u003eRetail operators’ operating and risk-management costs\u003c/li\u003e\n\u003cli\u003eTaxes, levies, and policy costs\u003c/li\u003e\n\u003cli\u003eThe method used to reflect prices in fixed-rate plans or long-term contracts\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eIt therefore cannot be assumed that the new interconnector will necessarily lower consumer rates. The net effect must be assessed by considering the generation costs saved through congestion relief, the costs of constructing and operating the power network, and each country’s rate regulations.\u003c/p\u003e\n\u003ch3\u003e\n\u003ca href=\"#security-of-supply\" class=\"anchor\" id=\"security-of-supply\"\u003e\u003c/a\u003eSecurity of Supply\u003c/h3\u003e\n\u003cp\u003eThe interconnector increases the options for procuring power from the other side when one country experiences power plant failures, drought, extreme heat, or an unexpected increase in demand. It also broadens the scope for the two countries to share required reserve capacity.\u003c/p\u003e\n\u003cp\u003eHowever, as interconnection increases, the risk that frequency disturbances or large-scale equipment failures in one region may spread to another must also be managed. This is why automatic protection systems, emergency power exchange procedures, joint training among transmission system operators, and real-time information sharing are necessary.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#interconnection-with-france-and-the-energy-island-problem\" class=\"anchor\" id=\"interconnection-with-france-and-the-energy-island-problem\"\u003e\u003c/a\u003eInterconnection with France and the Energy Island Problem\u003c/h2\u003e\n\u003cp\u003eThe Iberian Peninsula has long been described as an “energy island” because its power-grid connections with the center of continental Europe are relatively limited. Even if bottlenecks between Spain and Portugal are reduced, there will still be limits on sending surplus electricity from Iberia as a whole to other parts of Europe unless sufficient exchange capacity is available across the Pyrenees from Spain to France.\u003c/p\u003e\n\u003cp\u003eThis structure creates the following problems.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eExport destinations are limited when Spain and Portugal simultaneously generate large amounts of solar and wind power.\u003c/li\u003e\n\u003cli\u003ePrice differences between France and the Iberian Peninsula may persist for extended periods.\u003c/li\u003e\n\u003cli\u003eIn circumstances affecting all of Iberia, such as drought or a prolonged period of low wind speeds, capacity for imports from outside the region may be insufficient.\u003c/li\u003e\n\u003cli\u003eCongestion may recur if investment in renewable generation, green hydrogen, and electrified industries grows faster than domestic transmission networks and cross-border interconnections.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eNew interconnection projects toward France are a key task in integrating the Iberian market more deeply with the European electricity market. At the same time, domestic transmission networks in Galicia and northern Portugal must be reinforced, storage facilities expanded, and grid-stabilization resources secured.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#indicators-for-assessing-future-effects\" class=\"anchor\" id=\"indicators-for-assessing-future-effects\"\u003e\u003c/a\u003eIndicators for Assessing Future Effects\u003c/h2\u003e\n\u003cp\u003eThe performance of the new interconnector is difficult to evaluate based solely on its nominal capacity at completion. At a minimum, the following indicators must be monitored across multiple seasons.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eAssessment Area\u003c/th\u003e\n\u003cth\u003eIndicators to Monitor\u003c/th\u003e\n\u003cth\u003eSignificance\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Assessment Area\"\u003eUtilization\u003c/td\u003e\n\u003ctd data-label=\"Indicators to Monitor\"\u003eElectricity flows by direction and time of day, utilization relative to available capacity\u003c/td\u003e\n\u003ctd data-label=\"Significance\"\u003eShows how often the interconnector is actually used and in which direction.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Assessment Area\"\u003eMarket integration\u003c/td\u003e\n\u003ctd data-label=\"Indicators to Monitor\"\u003eHours of price separation between Spain and Portugal, average price difference\u003c/td\u003e\n\u003ctd data-label=\"Significance\"\u003eMeasures congestion relief and market-coupling effects.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Assessment Area\"\u003eRenewable energy\u003c/td\u003e\n\u003ctd data-label=\"Indicators to Monitor\"\u003eVolume of wind and solar curtailment, hours of negative prices\u003c/td\u003e\n\u003ctd data-label=\"Significance\"\u003eIndicates whether the utilization of surplus generation has improved.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Assessment Area\"\u003eSecurity of supply\u003c/td\u003e\n\u003ctd data-label=\"Indicators to Monitor\"\u003eEmergency import and export volumes, hours of supply shortages, reserve procurement costs\u003c/td\u003e\n\u003ctd data-label=\"Significance\"\u003eShows improvements in crisis-response capabilities and reliability.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Assessment Area\"\u003eConsumer impact\u003c/td\u003e\n\u003ctd data-label=\"Indicators to Monitor\"\u003eWholesale prices, network charges, final retail rates\u003c/td\u003e\n\u003ctd data-label=\"Significance\"\u003eIdentifies the net effect of market benefits and infrastructure costs.\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Assessment Area\"\u003eGrid operation\u003c/td\u003e\n\u003ctd data-label=\"Indicators to Monitor\"\u003ePlanned and unplanned outages, congestion-management costs, redispatch costs\u003c/td\u003e\n\u003ctd data-label=\"Significance\"\u003eReveals new bottlenecks or operational constraints.\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eIn particular, the maximum figure of 4.2GW must be distinguished from actual available capacity. Even if annual utilization is low, the interconnector may have significant grid value if it serves as insurance by preventing supply shortages during demand spikes or equipment failures. Conversely, even if utilization is high, continued internal bottlenecks and repeated curtailment in both countries would signal a need for additional investment.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#overall-assessment\" class=\"anchor\" id=\"overall-assessment\"\u003e\u003c/a\u003eOverall Assessment\u003c/h2\u003e\n\u003cp\u003eThe new Spain-Portugal interconnector is critical infrastructure that strengthens the physical foundation of MIBEL and enables renewable energy to be used across a broader region. The approximately 1GW of additional exchange capacity could reduce price differences, curtailment, and the risk of supply shortages in the two countries.\u003c/p\u003e\n\u003cp\u003eHowever, the interconnector itself does not guarantee inexpensive electricity or unlimited renewable-energy hosting capacity. Its actual performance will depend on the capacity made available to the market, the domestic grids of both countries, storage and demand response, interconnection toward France, and consumer-rate systems. Over the long term, these elements must be assessed as part of a single, integrated European power-system challenge.\u003c/p\u003e\n","tags":["Power grid","Renewable Energy","Spain","Portugal","Energy Market"],"faqs":[{"question":"How much did the new Spain–Portugal interconnector increase transmission capacity?","answer":"According to the European Commission's announcement, it added about 1 GW of electricity exchange capacity, raising the maximum exchange capacity between the two countries to about 4.2 GW. However, the capacity actually available to the market varies depending on maintenance, temperatures, internal congestion, and grid security standards."},{"question":"Does electricity flow only from Spain to Portugal?","answer":"No. The AC interconnector operates bidirectionally, and the direction of flow changes depending on market prices, power generation, demand, and grid conditions. The available capacity in each direction is not always the same."},{"question":"Will increased interconnection eliminate renewable energy curtailment?","answer":"It is more likely to reduce curtailment, but it will not eliminate it completely. There must be demand on the other side, and sufficient capacity is also needed in the internal transmission grid connecting generation areas to the border, as well as in storage systems and demand response."},{"question":"Will the new interconnector immediately lower consumers' electricity bills?","answer":"It can mitigate spikes in wholesale prices and price differences between the two countries, but it does not guarantee lower final rates. Consumer electricity bills also reflect grid charges, infrastructure investment costs, taxes, policy costs, and retail contract terms."},{"question":"How does the maximum capacity of 4.2 GW differ from the actual volume of electricity traded?","answer":"4.2 GW is the maximum amount of power that can be exchanged at a given moment. The amount of electricity actually traded over a certain period is expressed in GWh or TWh and is determined by available capacity at different times and market conditions."},{"question":"How does the interconnector improve the security of electricity supply?","answer":"It provides more options to receive electricity from a neighboring country in the event of power plant failures, droughts, heat waves, or surges in demand. However, protective devices, reserve capacity, and a coordinated response among transmission system operators are needed to prevent widespread outages from cascading."},{"question":"Will completion of the Spain–Portugal interconnector solve the Iberian Peninsula's energy island problem?","answer":"No. Integration between the two countries will be strengthened, but interconnection capacity toward France, which links the Iberian Peninsula to continental Europe, remains limited. Both the interconnection with France and the internal transmission grids of Spain and Portugal must be expanded to enable integration with the broader European market."},{"question":"Will electricity prices in Spain and Portugal always be the same?","answer":"If cross-border interconnection capacity is sufficient, the two prices may become equal or close. If the required exchange volume exceeds the available capacity, the markets will split, causing the price difference between the two countries to reappear."}],"sources":[{"url":"https://energy.ec.europa.eu/news/energy-union-new-spain-portugal-electricity-interconnection-inaugurated-2026-07-02_en","title":"European Commission: Energy Union—new Spain-Portugal electricity interconnection inaugurated","type":"data_point"},{"url":"https://economy-finance.ec.europa.eu/economic-surveillance-eu-member-states/country-pages-including-country-reports/spain/economic-forecast-spain_en","title":"European Commission: Economic forecast for Spain","type":"source"}],"images":[{"id":494,"url":"https://injoys.com/rails/active_storage/blobs/proxy/eyJfcmFpbHMiOnsiZGF0YSI6NTg3NSwicHVyIjoiYmxvYl9pZCJ9fQ==--02b362eb47e323fc1ca1c3ca22c650a9f0199066/ai-cf4c326d.webp","is_representative":true,"generation_method":"ai_image","license":"ai_generated","mime_type":"image/webp","translations":{"ko":{"alt":"스페인과 포르투갈의 전력망, 재생에너지 시설, 양방향 전력 흐름을 나타낸 이베리아반도 지도","caption":"신규 연계선을 통한 스페인과 포르투갈 간 양방향 전력 교환을 보여준다.","description":null},"en":{"alt":"Map of Iberia showing Spanish and Portuguese power grids, renewable energy sites, and two-way electricity flow","caption":"The illustration shows two-way electricity exchange between Spain and Portugal through a new interconnector.","description":null},"ja":{"alt":"スペインとポルトガルの送電網、再生可能エネルギー施設、双方向の電力融通を示すイベリア半島の地図","caption":"新たな連系線を通じたスペインとポルトガル間の双方向の電力融通を示している。","description":null},"es":{"alt":"Mapa ibérico con las redes eléctricas de España y Portugal, energías renovables y flujo bidireccional","caption":"La ilustración muestra el intercambio eléctrico bidireccional entre España y Portugal mediante una nueva interconexión.","description":null},"id":{"alt":"Peta Iberia dengan jaringan listrik Spanyol dan Portugal, energi terbarukan, serta aliran listrik dua arah","caption":"Ilustrasi ini menunjukkan pertukaran listrik dua arah antara Spanyol dan Portugal melalui interkoneksi baru.","description":null},"pt":{"alt":"Mapa ibérico com as redes elétricas de Espanha e Portugal, energias renováveis e fluxo bidirecional","caption":"A ilustração mostra a troca bidirecional de eletricidade entre Espanha e Portugal através de uma nova interligação.","description":null},"zh-hant":{"alt":"伊比利半島地圖，呈現西班牙與葡萄牙電網、再生能源設施及雙向電力流動","caption":"圖中顯示西班牙與葡萄牙透過新互聯線進行雙向電力交換。","description":null},"de":{"alt":"Karte der Iberischen Halbinsel mit Stromnetzen, erneuerbaren Energien und Stromfluss zwischen Spanien und Portugal","caption":"Die Grafik zeigt den wechselseitigen Stromaustausch zwischen Spanien und Portugal über eine neue Verbindungsleitung.","description":null}}},{"id":495,"url":"https://injoys.com/rails/active_storage/blobs/proxy/eyJfcmFpbHMiOnsiZGF0YSI6NTg4MSwicHVyIjoiYmxvYl9pZCJ9fQ==--40edefd9c5b28f7d9fac7979501d4a96574be4a1/ai-28bed28d.webp","is_representative":false,"generation_method":"ai_image","license":"ai_generated","mime_type":"image/webp","translations":{"ko":{"alt":"재생에너지 설비와 국경 간 송전망이 표시된 이베리아반도 전력 지도","caption":"스페인과 포르투갈의 전력망이 프랑스·북아프리카 및 인근 섬과 연결된 모습을 나타낸다.","description":null},"en":{"alt":"Map of the Iberian power grid with renewable energy sites and cross-border links","caption":"The illustration shows Spain and Portugal connected to France, North Africa, and nearby islands by power lines.","description":null},"ja":{"alt":"再生可能エネルギー設備と国際連系線を示すイベリア半島の電力網地図","caption":"スペインとポルトガルの電力網がフランス、北アフリカ、周辺の島々につながる様子を示している。","description":null},"es":{"alt":"Mapa de la red eléctrica ibérica con energías renovables e interconexiones internacionales","caption":"La ilustración muestra las redes de España y Portugal conectadas con Francia, el norte de África y las islas cercanas.","description":null},"id":{"alt":"Peta jaringan listrik Iberia dengan energi terbarukan dan interkoneksi lintas batas","caption":"Ilustrasi menunjukkan jaringan Spanyol dan Portugal yang terhubung ke Prancis, Afrika Utara, dan pulau terdekat.","description":null},"pt":{"alt":"Mapa da rede elétrica ibérica com energias renováveis e interligações internacionais","caption":"A ilustração mostra as redes de Espanha e Portugal ligadas a França, ao Norte de África e às ilhas próximas.","description":null},"zh-hant":{"alt":"顯示再生能源設施與跨境輸電線的伊比利半島電網地圖","caption":"圖中呈現西班牙與葡萄牙電網連接法國、北非及鄰近島嶼的情況。","description":null},"de":{"alt":"Karte des iberischen Stromnetzes mit erneuerbaren Energien und grenzüberschreitenden Leitungen","caption":"Die Grafik zeigt die Stromnetze Spaniens und Portugals mit Verbindungen nach Frankreich, Nordafrika und zu nahen Inseln.","description":null}}}],"published_at":"2026-08-06T00:50:26+09:00","updated_at":"2026-08-06T00:50:26+09:00","license":"cc_by","translation_status":"reviewed","available_locales":["ko","en","ja","es"],"data_locales":["ko","en","ja","es","id","pt","zh-hant","de"],"url":"https://injoys.com/en/articles/spain-portugal-new-electricity-interconnection"}