The Supreme Court has overturned the Royal Decree that regulated the Installation of floating photovoltaic plants in reservoirs under public water domain managed by the General State Administration. The decision responds to an appeal filed by the Government of Aragon and represents a significant shift in how these types of renewable energy projects on water bodies are promoted in Spain.
The key issue has not been so much the environmental or energy content of the regulation, but rather the way in which it was approved. The Supreme Court understands that the central government The prior public consultation process was skipped without the exceptional circumstances that would allow dispensing with that participatory phase, which leads to the declaration of nullity of the Royal Decree as a whole.
Which law has the Supreme Court overturned and why was it important?
The court ruling affects the Royal Decree that established the specific legal framework for floating photovoltaic plants in reservoirs located in river basins under state jurisdiction, as well as the modification of the Regulations for the Public Water Domain necessary to accommodate this new type of use. In practice, this text established the basic rules for authorizing and operating these solar water installations.
The central government's objective with this regulation was to enable a common framework that would facilitate deployment floating photovoltaic projects in reservoirs, in line with the commitment to accelerate renewable energy and utilize existing areas—such as reservoirs—to generate electricity without occupying additional land. The Royal Decree detailed technical, environmental, and administrative conditions to ensure compatibility between these uses and other water resources.
However, the Supreme Court ruling indicates that, despite the strategic relevance of the regulation, the regulatory development procedure It omitted an essential step: prior public consultation. provided for in the legislation on good governance and regulatory transparency. This procedural deficiency, and not the substantive content, is what leads the Supreme Court to declare the text null and void.
The ruling emphasizes that this is not a mere formality. In the opinion of the Administrative Court, the prior consultation is a phase designed to Gather opinions from affected citizens, organizations and administrations, especially relevant when the regulation has a significant territorial and environmental impact, as is the case with photovoltaic installations on reservoirs.
The Aragon resource: transparency, powers and impact on the territory
The legal initiative came from the Government of Aragon, which decided to challenge the Royal Decree, considering that It violated principles of good regulation and transparency.In addition to impacting areas where the autonomous community has its own powers, the Aragonese community had already publicly expressed its opposition to the proliferation of floating solar panels on its reservoirs.
Among the arguments put forward, Aragón maintained that the State had improperly applied a reduction in deadlines and procedures, shortening the public hearing and information phases and omitting the prior consultation process without a clear justification of urgency. According to the regional government, there was no extraordinary situation that would allow them to bypass this participatory procedure.
Furthermore, the appeal emphasized that the location of floating photovoltaic plants in reservoirs affects regional powers such as environment, land management, tourism, sports, inland fishing and hydroelectric power generationThe Aragonese complaint pointed out that the state regulation generated direct effects on these areas without articulating specific mechanisms for regional intervention beyond those already provided for in the general sectoral regulations.
The Government of Aragon also questioned the way in which the drafting process of the Royal Decree had been publicized. According to its legal services, on the Transparency Portal Only the draft regulation, the Regulatory Impact Analysis Report, and the opinion of the Council of State were disseminated.but not the rest of the required reports and opinions, which, in his opinion, diminished the clarity and completeness of the available information.
In parallel to the appeal, the president of Aragon, Jorge Azcón, had announced his intention to promote specific legislation for restrict the installation of floating solar panels in community reservoirs, arguing a negative impact on the environment, rural tourism, recreational use of water and the interests of irrigators who depend on these hydraulic infrastructures.
The Supreme Court's criteria on public consultation and urgency
The Administrative Chamber of the Supreme Court focuses its analysis on determining whether it was justified to dispense with the prior public consultation processState regulations allow this step to be avoided only in specific cases, such as when dealing with organizational or budgetary rules, or when there is a duly declared and justified urgent procedure.
In this case, the High Court dismisses each of those possibilities individually. On the one hand, it indicates that the Royal Decree on floating photovoltaic plants It has no organizational or budgetary natureRather, it establishes a new system for the use of public water resources with broad sectoral and territorial implications. Therefore, it does not fall under the exceptions that allow for bypassing the consultation process.
On the other hand, the ruling emphasizes that There is no record of a formal declaration of urgency in the processing of the regulation, nor a procedure built on that legal basis. Although the State Attorney's Office argued that there were "serious reasons of public interest" linked to the increase in energy costs and the need to reinforce the supply, the Supreme Court considers that these arguments are not sufficient if they did not translate into a declaration of urgency with the required legal formalities.
The court acknowledges the importance of facilitating investment in renewables in a context of high prices and tension in energy markets, but notes that Accelerating the energy transition cannot come at the cost of sacrificing basic procedural safeguards.The prior public consultation, it points out, is a key instrument for social agents, Administrations and citizens to be able to express their opinions before the regulation is finalized.
Consequently, the Court concludes that The omission of prior consultation is a substantial defect of the regulatory procedure, which cannot be remedied after the fact nor considered harmless. This deficiency entails the nullity of the Royal Decree, without it being necessary to review each of its provisions in detail from a substantive point of view.
Environmental impact, uses of the reservoir and position of Aragon
Although the ruling focuses on the procedural issue, the case file and the appeal from Aragon raise a fundamental debate: How to reconcile floating solar energy with the other uses and values ​​of reservoirsThe autonomous community believes that these facilities may have significant impacts on the landscape and the environment.
In its arguments, Aragon pointed to possible negative impacts on the landscape and, by extension, the tourist appeal of certain areas linked to reservoirs with a high volume of visitors. It also highlighted the repercussions on recreational and sporting activities, such as boating or certain types of inland fishing, which could be affected by the presence of large areas covered by slabs.
Another point raised was the protection of the aquatic environment. The regional government warned that the installation of floating structures could lead to Risks of material degradation, accidental spills, and alteration of the ecological potential of water bodiesaffecting water quality, submerged flora and fauna associated with these ecosystems.
In addition, the irrigators' concerns were raised about a possible detriment to the agricultural use of water resourcesThis is due both to the physical occupation of the water surface and to potential interference with the water intake and distribution infrastructure. The Aragonese government argued that, without a detailed assessment and greater community involvement in decision-making, the balance between renewable energy and traditional water uses could be disrupted.
Against this backdrop, the annulment of the Royal Decree effectively strengthens Aragon's ability to design its own more restrictive internal regulations on floating photovoltaic panels in reservoirs located in their territory, at least until a new state framework is established with a procedure fully in accordance with legal requirements.
Regional powers, good regulation and the effects of the ruling
The ruling also addresses other objections raised by Aragon, although it does not give them the same weight as the lack of public consultation. The Supreme Court is analyzing whether the Royal Decree encroached on regional powers or generally violated the principles of good regulation contained in the basic regulations.
At this point, the High Court concludes that the state regulation neither eliminated nor ignored the intervention that Sectoral laws already assign powers to the autonomous communities in matters such as the environment, land use planning, and natural resource management. In their view, the challenged regulation established a general framework for state-owned water resources without eliminating existing regional powers.
Regarding the principles of good regulation—necessity, proportionality, legal certainty, transparency, and efficiency—the Court understands that, leaving aside the problem of prior public consultation, The regulation pursued a legitimate and appropriate aim related to the promotion of renewable energies and the optimized use of existing hydraulic infrastructure. Therefore, it does not find a material infringement of these principles in the content.
The practical effect of the ruling is that the Royal Decree is completely nullified and ceases to produce effectsThis implies that the State loses the specific regulation it had designed for floating photovoltaic plants in reservoirs under public water domain, requiring, if it wants to regulate this matter again, to initiate a new regulatory procedure respecting all the formalities, including prior consultation.
For floating solar energy projects already underway or in the planning stage, the scenario becomes more complex. The absence of a detailed state framework for this type of facility This may generate uncertainty for administrations, developers and users of reservoirs, while awaiting clarification of the legal framework through new regulations or the application of general hydraulic and energy regulations.
The Supreme Court's ruling serves as a wake-up call to the state legislature regarding the importance of respect the channels of participation and transparency even when the aim is to accelerate developments linked to the energy transition. The annulment does not close the debate on floating photovoltaic plants, but it does force a rethinking of how they are regulated, incorporating the voices of the territories and potentially affected stakeholders with greater weight.
With this ruling, the deployment of floating solar energy on reservoirs in Spain is conditioned by a delicate balance between the need to promote renewables, the guarantees of good regulation, and the protection of existing water uses, so that any future state regulation will have to to be born from a much more participatory and meticulous procedure if he wants to endure without stumbling before the courts.