The Spanish Energy Market: How Flexible Access Permits Change Hybrid Project Economics
Key points
- Spain’s rapid renewable buildout is increasing solar price cannibalisation, making the timing of generation, storage and consumption increasingly important to project economics.
- Grid congestion is becoming a critical development constraint, with approximately 83.4% of distribution nodes saturated for new demand.
- The CNMC’s new flexible access framework creates opportunities for electricity demand to connect where firm capacity is unavailable, subject to defined operational restrictions.
- Combining solar, BESS and flexible demand can help developers improve the utilisation and economic value of constrained grid connections. Gridcog enables developers to model these configurations and assess their financial performance.
On this page
- How is Spain’s renewable buildout changing the power market?
- Why are grid constraints and solar cannibalisation becoming a risk?
- Flexible demand creates a new route through grid constraints
- How Type 0 affects project operations and economics
- Hybridisation: extracting more value from constrained grid access
- How do you model flexible demand in Gridcog?
- FAQs
Spain has built one of Europe’s largest renewables fleets, with around 50 GW of solar PV and 33 GW of wind installed by early 2026. As you would expect, that build-out is changing how the market works. Growing solar is concentrating generation into the same hours of the day, and prices in those hours are falling with it. Spain recorded 397 hours of negative prices in Q1 2026, up from 48 a year earlier, and the average solar captured price fell from €42.28/MWh in 2024 to €29.68/MWh in H1 2026.
This pressure will continue to grow. The updated National Energy and Climate Plan (PNIEC) targets 81% renewable electricity by 2030, including 76 GW of solar PV, 62 GW of wind and 22.5 GW of storage, even though grid capacity for new projects is already scarce.
For developers and IPPs, value therefore depends less on how much energy an asset can produce, and increasingly on when it can generate, store or consume it, and what grid access is available to do so.
How is Spain’s renewable buildout changing the power market?
As solar pushes prices down in the middle of the day, the gap between low-price and high-price hours widens. Spain’s day-ahead, intraday and balancing markets are volatile, giving flexible assets several ways to earn revenue. For developers, this creates both risk and opportunity. Inflexible generation faces greater cannibalisation, while assets that can shift generation or consumption across time see stronger price signals. A battery can charge during low or negative price hours and discharge into the evening peak, and flexible demand can move consumption into the cheapest hours of the day.
However, the ability to capture these opportunities depends not only on market prices, but also on access to the electricity network. Even where battery storage and flexible demand could help absorb renewable generation and improve system flexibility, projects still need sufficient grid capacity to connect and operate, which is exactly the challenge Spain is facing today.
Figure 1: June 2026 average day-ahead prices: €12/MWh in the solar trough, €136/MWh at the evening peak.
Why are grid constraints and solar cannibalisation becoming a risk?
Generation projects in Spain are already facing significant constraints. In 2025, renewable developers requested 40 GW of grid access, but only 4.5 GW was approved, while a further 25 GW was rejected due to insufficient network capacity.
The situation is similarly challenging for new electricity demand. Capacity maps published by distribution network operators showed that approximately 83.4% of distribution nodes were saturated for new demand: around 67 GW of demand connection capacity was requested in 2024, with a significant proportion of applications unable to secure access. To put this into perspective, the requested capacity was approximately 1.7 times the Spanish peninsular electricity system’s peak demand of 40 GW recorded in 2025, highlighting the significant mismatch between growing electricity demand and available grid infrastructure.
This affects many of the technologies expected to support Spain's energy transition, including industrial electrification, data centres, energy storage, hydrogen production and electric mobility.
The challenge is also often local. Capacity may exist elsewhere in the electricity system, but not at the specific connection point required by a project. As grid infrastructure struggles to keep pace with new energy projects, securing a connection is becoming an increasingly important factor in project development.
Flexible demand creates a new route through grid constraints
Grid access is no longer necessarily a binary choice between obtaining unrestricted capacity and being unable to connect. In July 2026, the Comisión Nacional de los Mercados y la Competencia (CNMC) adopted a new framework for flexible access permits for electricity demand.
Under this framework, eligible projects may be approved where firm capacity is unavailable, provided they accept specific operational restrictions designed to protect network security.
Instead of assessing only whether a connection point has sufficient capacity at all times, developers can consider when capacity may be available and whether their projects can operate within those limits.
The framework establishes four types of flexible access permits, each with different operating conditions:
- Type 0 – Predefined import schedules: Allows electricity consumption during specified hours of the day, following a predefined access pattern.
- Type 1 – Remote disconnection: Allows the distribution network operator to temporarily disconnect consumption when specific network constraints arise.
- Type 2 – Flexible power curtailment: Allows the distribution network operator to partially or fully reduce electricity consumption, either through scheduled instructions or in real time.
- Type 3 – Automatic power reduction: Applies to eligible consumers connected to the transmission network, requiring automatic reductions in consumption when instructed by the system operator to maintain network security.
Types 0, 1 and 2 apply to demand connected to distribution networks, including battery storage when importing electricity. Type 3 applies to eligible consumers connected to the transmission network, while electricity imports for battery storage connected to transmission are subject to a separate flexible access framework.
The framework also establishes implementation deadlines. Distribution Network Operators (DNOs) must make Type 0 and Type 1 flexible access permits available to eligible applicants within six months of the regulation taking effect on 1 September 2026, while Type 2 must be implemented by 1 January 2028.
For developers, the commercial question is this - what constraint applies at the site, and can the project create value within it?
How Type 0 affects project operations and economics
Type 0 is the most immediately relevant framework because it establishes predefined periods during which a project can import electricity from the grid. Unlike access arrangements that depend on dynamic curtailment or disconnection instructions, a predefined schedule provides greater visibility over the operating restrictions that a project must accommodate, supporting a more conservative and predictable approach to revenue forecasting than a fully dynamic access regime.
For example, the Type 0.1 profile permits grid imports between 00:00–07:59 and 11:00–17:59. A project may therefore be able to import electricity during these defined periods even where unrestricted firm access is unavailable.
Figure 2: Type 0 pattern 0.1: imports permitted 00:00–07:59 and 11:00–17:59.
This creates a direct opportunity for flexible loads, storage and hybrid projects to use grid capacity when it is most available which in many cases coincides with when electricity is cheapest.
Developers must therefore work out which asset mix delivers the most value within the access window they’ve been granted.
This is where the combination of solar PV, battery energy storage systems (BESS) and flexible electricity demand becomes particularly relevant.
Hybridisation: extracting more value from constrained grid access
Once access is defined by an hourly constraint, the value of the project depends increasingly on how the assets behind that connection are configured.
A flexible load - for example, heating, pumping or cooling - can shift consumption into permitted import hours, while solar PV can supply part of that demand directly. Batteries add flexibility by storing electricity during permitted import periods or from surplus solar generation, and supplying energy when grid imports are restricted or market prices are higher.
By combining these assets, developers can reduce renewable energy curtailment, optimise consumption and increase the economic value of their grid connection.
The next step is to work out which combination of solar, BESS and flexible demand performs best financially within the same grid constraint. Dynamic techno-economic modelling is what makes that possible.
How do you model flexible demand in Gridcog?
Step 1: Create your grid import constraint for each hour of the day
The first step is to create an Import Schedule in the Gridcog Library.
This schedule defines the hours in which grid imports are allowed, allowing developers to represent flexible access conditions such as a Type 0 consumption profile.
Step 2: Apply the schedule to the Site Meter
When building your project, the Import Schedule is assigned to the site meter.
This applies the import constraint directly to the point of connection, ensuring that grid imports are only available during the hours defined in the schedule.
Step 3: Optimise the project within the constraint
Once the schedule is applied, Gridcog incorporates the import restrictions into the dispatch of the assets.
This makes it possible to assess the impact of flexible access across different project configurations - from behind-the-meter projects combining load, solar and storage to front-of-meter co-located PV + BESS projects.
Figure 3: A battery inside a Type 0 window: charges overnight and from solar at midday, discharges into the evening peak.
Developers can then compare different configurations and understand how the same flexible access profile affects grid imports, asset dispatch and overall project economics.
Talk to our team about modelling Type 0 access windows, co-located solar and BESS, and flexible demand for your Spanish projects in Gridcog.
FAQs
What are flexible access permits in Spain?
Flexible access permits let new electricity demand connect at network nodes where no firm capacity is available, in exchange for accepting defined operating constraints. The CNMC adopted the framework on 31 July 2026 and it took effect on 1 September 2026. Constraints range from a predefined hourly consumption pattern (Type 0) to automatic power reduction at transmission level (Type 3).
When can developers apply for Type 0 and Type 1 permits?
Type 0 and Type 1 permits are intended to become available within six months of the CNMC resolution taking effect on 1 September 2026. As of October 2026, e-distribución says it will process Type 0 and Type 1 applications above 30 kV from 1 March 2027. Type 2 permits are due once the distribution network operator has the control tools in place, and no later than 1 January 2028.
Do battery storage projects need a flexible access permit in Spain?
Yes. Under the CNMC resolution, battery storage projects are subject to flexible access conditions when importing electricity from the grid.
Batteries can both consume and inject electricity into the grid. When charging, they are treated as electricity demand and must comply with the applicable flexible access conditions. When discharging electricity into the grid, they operate under their corresponding generation access permits.
The CNMC resolution also establishes transitional provisions for storage projects with previously granted access permits.
Which voltage levels do Type 1 and Type 2 permits cover?
At first, Type 1 and Type 2 permits on distribution networks apply only where the connection point is at 30 kV or above. The CNMC plans to lower the threshold later to voltages above 1 kV, extending the permits to more medium-voltage sites. Type 2 also applies only to installations with flexible power above 1 MW on the peninsular system.
What is the difference between Type 2 and Type 3 permits?
The main difference is the network they apply to and how electricity consumption is restricted.
Type 2 applies to eligible consumers connected to distribution networks. The distribution network operator can partially or fully reduce their electricity consumption, either through scheduled instructions or in real time.
Type 3 applies to eligible consumers connected to the transmission network. These consumers must be able to automatically reduce their electricity consumption when required by the system operator to maintain grid security.
Can Gridcog model a Type 0 flexible access permit?
Yes. You create an Import Control Schedule in the Gridcog Library that defines the hours when grid imports are allowed, then assign it to the project’s site meter. Gridcog’s optimiser then dispatches the site within that constraint, so you can compare how solar, BESS and flexible demand configurations perform under the same access profile.
Sources
- CNMC, ‘La CNMC aprueba la regulación que facilitará la conexión de nuevos consumidores a la red eléctrica mediante permisos de acceso flexible’, 11 August 2026
- BOE, ‘Resolución de 31 de julio de 2026, de la CNMC, por la que se establecen los permisos de acceso flexibles de la demanda’, 2026
- e-distribución, ‘Generation capacity access at network nodes’, accessed 13 October 2026
- pv magazine, ‘Spain sets new 2030 solar target of 76 GW’, 25 September 2024
