Key data
| Regulation | Resolution of June 26, 2026, from the General Directorate of Quality and Environmental Assessment — environmental impact report for the project «Modification of the reversible hydroelectric plant Moralets II» |
|---|---|
| Publication | July 11, 2026 |
| Effective date | July 11, 2026 |
| Promoter | Endesa Generación SA |
| Location | Montanuy, province of Huesca |
| Turbination power | 420 MW |
| Pumping power | 400 MW |
| Total combined power (Moralets I + II) | 630 MW |
| Status of works when halted | 25-30% executed (halted since 2014) |
| Original EIA in force | Environmental Impact Statement of 2008 |
| Category | Energy / Environmental Assessment |
| Official source | BOE-A-2026-15188 |
The works of the reversible hydroelectric plant Moralets II have been halted for twelve years. Since 2014, with between 25% and 30% of construction already completed, the project awaited the environmental resolution that would allow incorporating the technical adjustments introduced compared to the original project. With the Resolution of June 26, 2026, published in the BOE on July 11, 2026, that blockage is lifted.
The promoter, Endesa Generación SA, can now resume construction in the municipality of Montanuy (Huesca), incorporating the construction changes evaluated in this simplified report.
What does this regulation establish?
The resolution issues a simplified environmental impact report for the modification of the Moralets II project. It does not replace the original Environmental Impact Statement (EIA) of 2008, which remains in force: the assessment is limited exclusively to the changes introduced compared to that already approved project.
The construction adjustments that have motivated this new environmental assessment are as follows:
- Expansion of the penstock diameter
- Hydraulic short-circuit between units
- Auxiliary access works
From a hydraulic perspective, the project does not alter the hydraulic regime nor does it imply additional net water consumption: the plant operates in a closed circuit between the reservoirs of Llauset and Baserca, pumping water during low demand hours and turbinating it during peak hours.
| Aspect | Original project (EIA 2008) | Modification assessed (2026) |
|---|---|---|
| Turbination power | 420 MW | No change |
| Pumping power | 400 MW | No change |
| Penstock diameter | Original diameter | Expanded |
| Hydraulic short-circuit between units | Not contemplated | Incorporated |
| Auxiliary access works | Original configuration | Adjusted |
| Hydraulic regime / net water consumption | Closed circuit | No alteration |
Economic and operational impact
The resumption of Moralets II has direct consequences in several areas:
- For Endesa Generación SA: an investment already initiated in 2012 with 25-30% executed is unblocked. The company can resume construction without needing a new complete EIA, which significantly reduces administrative timelines.
- For the Spanish electrical system: the plant will provide 420 MW of turbination capacity and 400 MW of pumping, adding 630 MW of total power when combined with Moralets I. Reversible plants are key assets for integrating variable renewable energies (solar and wind), acting as large-scale "batteries".
- For the territory: the reactivation of works generates economic activity and employment in Montanuy (Huesca) and the surrounding Barravés Valley area, with implications also for the Catalan municipality of Vilaller, close to the Llauset and Baserca reservoirs.
- For the electricity market: greater pumped storage capacity contributes to price stabilization during peak hours and reduction of renewable spillage.
Who does it affect?
- Endesa Generación SA — project promoter, directly authorized to resume works
- Administration of Aragón — territorial and planning competencies in Montanuy (Huesca)
- Administration of Catalonia — affected by the proximity of the reservoirs (Llauset and Baserca) and the municipality of Vilaller
- Municipality of Montanuy (Huesca) — main location of the works
- Municipality of Vilaller (Lleida) — affected by the hydraulic infrastructure involved
- Electricity market operators — greater pumped storage capacity in the peninsular system
- Construction and auxiliary companies — resumption of contracts and tenders linked to the work
Practical example
Imagine you are a contractor or civil engineering services provider who participated in the Moralets II works before its halting in 2014. At that time, the works stopped with between 25% and 30% executed. With the favorable environmental report published on July 11, 2026, Endesa Generación SA is in legal conditions to resume construction.
This means that the pending execution phase —between 70% and 75% of the remaining work— can be tendered or reactivated. The approved technical adjustments (expansion of the penstock diameter, hydraulic short-circuit between units and auxiliary access works) are those that must be incorporated into the updated execution project. A new complete EIA is not required: the one from 2008 remains valid, which considerably shortens timelines.
What should companies do now?
- Endesa Generación SA: review the execution project to incorporate the three approved construction adjustments (penstock diameter, hydraulic short-circuit and auxiliary access works) before resuming works.
- Contractors and linked suppliers: contact Endesa to learn about the resumption schedule and the new technical specifications that reflect the approved modifications.
- Administrations of Aragón and Catalonia: coordinate the municipal and regional permits necessary for resumption, bearing in mind that the 2008 EIA remains in force and the 2026 report covers the specific changes.
- Municipalities of Montanuy and Vilaller: update territorial and services planning in anticipation of the reactivation of construction activity in the area.
- Electricity market operators and grid managers: incorporate the future availability of 630 MW combined (Moralets I + II) in the planning models of the peninsular electrical system.
Frequently asked questions
Why were the Moralets II works halted in 2014?
The works began in 2012 and were halted in 2014 with 25-30% of the project executed. The resolution does not specify the exact cause of the halt, but it does indicate that resumption required evaluating the construction adjustments introduced compared to the original project, which has resulted in this simplified environmental impact report published in July 2026.
Is a new Environmental Impact Statement necessary to resume the works?
No. The original 2008 EIA remains in force. The resolution of June 26, 2026 issues only a simplified environmental impact report that evaluates exclusively the changes compared to the already approved project: expansion of the penstock diameter, hydraulic short-circuit between units and auxiliary access works. It is not necessary to process a new complete EIA.
How much power will the Moralets complex have when completed?
The Moralets II plant will have 420 MW of turbination power and 400 MW of pumping power. Combined with Moralets I, the total installed power of the complex will reach 630 MW, making it a first-rate renewable energy storage infrastructure in the Spanish electrical system.
Does the project consume water from the river or the environment?
No. The plant operates in a closed circuit between the Llauset and Baserca reservoirs. It does not alter the hydraulic regime nor does it imply additional net water consumption: it pumps water during low electricity demand hours and turbinates it during peak hours, functioning as a large-scale hydraulic battery.
What administrations are involved in the resumption of works?
The affected administrations are the General Directorate of Quality and Environmental Assessment (which issues the report), the administration of the Autonomous Community of Aragón, the administration of the Generalitat of Catalonia, and the municipalities of Montanuy (Huesca) and Vilaller (Lleida), the latter directly affected by the location of the works and the hydraulic infrastructure.
Official source
Consult complete regulation in official source (BOE-A-2026-15188)
Notice: This article is for informational purposes only and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-15188