Summary of Judgment — High Court (Planning & Environment)

Case reference: [2025] IEHC 600 (Planning & Environment)

Judge: Judge Humphreys

Factual and Procedural Background

This judgment concerns judicial review proceedings brought by a group of local opponents and two individual applicants (collectively referred to below as "the Applicants") challenging a decision of the planning authority (referred to below as "the Defendant" or "the Commission") dated 21 November 2023 which granted planning permission for a seven turbine wind energy development and associated works at a rural site (the "Site"). The planning application was submitted by an agent on behalf of the notice party ("Company A"). The application included an Environmental Impact Assessment Report (EIAR) and a Natura Impact Statement (NIS) and was the subject of public consultation and submissions by prescribed bodies.

The Commission appointed an inspector who inspected the site, produced a report recommending permission subject to conditions, and the Commission then decided to grant permission subject to conditions. The Applicants issued two sets of proceedings: the present proceedings (challenging the parent permission) and a second set challenging an amendment (the second proceedings). The present judgment deals with the Module I phase of a modularised judicial review process (Module I addressing a number of core grounds other than the balance of core grounds 1 and 8A which were reserved for Module II).

Procedurally: the first proceedings were issued on 24 January 2024; leave to apply for judicial review was granted and an amended statement of grounds filed. The case was modularised and progressed on an expedited timetable. The hearings for the proceedings (both cases together) were held on 30 September and 1 October 2025. Judgment was reserved and a draft judgment circulated to parties on 15 October 2025. The present written judgment was delivered on 6 November 2025.

Legal Issues Presented

1. Whether the impugned decision was invalid because the decision‑maker accepted the application without, or despite absence of, required landowner consents for parts of the Site (Core Ground 1).
2. Whether the decision was invalid for failure to consider or for inadequate consideration of noise (including amplitude modulation) and shadow flicker, and for relying on outdated guidance rather than more recent scientific standards, with alleged failure to have regard to submissions from parents/guardians of vulnerable persons (Core Ground 2).
3. Whether the application contained inadequate plans and particulars for certain components (battery storage/substation and haul route works) such that the decision was invalid (Core Ground 4).
4. Whether the decision was invalid for procedural failure to make relevant documents publicly accessible through appropriate electronic portals and timeframes, contrary to transposed provisions of the EIA Directive and implementing legislation (Core Ground 5).
5. Whether the Environmental Impact Assessment (EIA) was defective because it failed properly to identify, describe or assess direct and indirect significant effects on population and human health (particularly noise) (Core Ground 6, derived from Core Ground 2).
6. Whether the decision amounted to unlawful project‑splitting by excluding from EIA assessment elements of the whole project (battery/substation/energy storage) (Core Ground 7).
7. Whether the EIAR failed to include an adequate outline of reasonable alternatives and reasons for the choice, as required by Article 5(3)(d) of the EIA Directive and CJEU authority (Core Ground 8).
8. Whether Article 214(1) of the Planning and Development Regulations 2001 (as amended) is invalid because it does not require written landowner consent for Strategic Infrastructure Development applications made by parties who are not landowners (Validity Ground / Core Ground 8A) — this was modularised to Module II.

Arguments of the Parties

Plaintiffs' Arguments

• The planning application should not have been accepted in respect of turbines said to be located on land of particular individual applicants because letters of landowner consent were not given; the Commission knew or ought to have known this and should have refused to deal with the application (Core Ground 1).
• The Commission failed to properly consider issues of wind turbine noise (including amplitude modulation) and shadow flicker, and relied on outdated (2006) wind energy guidance rather than best current scientific practice and the draft 2019 guidance; the Commission did not adequately address submissions from parents/guardians of vulnerable persons who fear health impacts (Core Ground 2 and related EIA complaint Core Ground 6).
• The EIAR and application lacked adequate or legible plans and particulars for the battery storage facility, substation and haul route works, contrary to article 214(1) (Core Ground 4).
• The public were not provided with relevant information via a central electronic portal within reasonable timeframes; documents were not all available on the developer's website or appropriately signposted (Core Ground 5).
• The EIAR did not adequately describe or assess direct and indirect effects on population and human health (Core Ground 6), or the environmental effects of reasonable alternatives in sufficient detail (Core Ground 8).
• Article 214(1) of the Regulations is constitutionally invalid for failing to require written landowner consent for SID applications (Core Ground 8A — reserved to Module II).

Defendant's (Commission's) Arguments

• If absence of landowner consent were legally material, the issue is rendered academic or addressed by the amendment decision in the separate proceedings (section 146B amendment): discretionary relief (certiorari) would be disproportionate in any event (response to Core Ground 1).
• The Commission had regard to the submissions (including those from consultees and the draft 2019 guidelines) and the inspector's report shows that the matters were considered; the complaints about noise, amplitude modulation (AM) and shadow flicker are either merits challenges or are not pleaded with the necessary evidential particularity (response to Core Ground 2 and 6).
• The application documentation (including EIAR annexes) contained adequate particulars about the battery/substation and haul route; some elements were identified as indicative or to be the subject of subsequent application but were assessed in the EIAR (response to Core Ground 4 and 7).
• Complaints about the central EIA portal implicate the Minister (State) rather than the Commission; no relief was sought against the Minister and there is no pleaded basis to quash the Commission's decision on that ground (response to Core Ground 5).
• Regarding alternatives (Core Ground 8), the EIAR contained the required outline of main alternatives and adequate reasons for the choice consistent with CJEU authority (Holohan): any allegation of inadequacy was not made out evidentially.

Notice Party (Company A) / Developer Arguments

• The developer acted in good faith and believed it had the necessary consents; absence of landowner consent (if relevant) does not automatically render the application invalid ab initio and the issue was rendered academic by the amendment decision removing turbines from the contested land.
• The EIAR and the inspector's assessment comprehensively addressed noise, AM and shadow flicker; the developer committed to mitigation measures including a zero‑shadow flicker operational approach and to monitoring and mitigation post‑commissioning.
• Details of haul route works, foundations and the indicative location of substation/battery storage were provided in the EIAR and annexes and were assessed by the inspector; the substation/ESS were not components for which consent was sought in the parent application but were assessed cumulatively in the EIAR.
• Claims that documents were missing from public portals were unparticularised and the notice party pointed out no evidence of prejudice to the Applicants' ability to participate in the process.

The State / Minister

• The State's role in maintaining the central EIA portal was noted; the Commission may not be the appropriate respondent on any complaint about the central portal and the Minister was not joined on that ground (as recorded in the judgment).

Table of Precedents Cited

Court's Reasoning and Analysis

The court set out a structured legal framework before addressing the pleaded grounds. Key elements of the court's approach included:

• Restatement of core judicial review principles: JR examines legality not merits; evaluative planning judgments are generally for the decision‑maker and are reviewable only on limited grounds (irrationality, procedural unfairness, legal error).
• Onus of proof: applicants bear the onus to demonstrate unlawfulness; where an error is established the onus may shift to opposing parties to show harmlessness. Allegations that depend on scientific or technical shortcomings generally require admissible expert evidence.
• Reasons: the standard is that main reasons on main issues must be provided; reasons may be implicit, found in adopted inspector reports, and need not be discursive or submission‑by‑submission.
• EIA/AA law: the court summarised EU law on EIA and Appropriate Assessment (AA), including project‑as‑a‑whole principles, cumulative/in‑combination effects, the standard that AA must dispel reasonable scientific doubt, and the Holohan principle that only an outline of alternatives and reasons for selection is required (not full assessment for each alternative).
• Harmless error doctrine: the court reviewed EU and domestic authorities (including Altrip and related case law) and explained that a decision should not be quashed if an identified error was harmless (i.e., the court can exclude a reasonable possibility that the error affected the outcome), and that the court may receive evidence (including from developers) to assess harmlessness.

Applying those principles to the pleaded grounds, the court reached the following central analytical conclusions:

• Core Ground 1 (landowner consent): The court analysed the applicants' contention that the Commission should have refused to deal with the application because of an absence of landowner consents for turbines said to be on certain land. The court accepted that, if relevant, the consent issue could be material but found that (a) the point may be academic in light of an amendment decision (section 146B) in the related proceedings which moved the turbines off the contested land (an outcome that would remove the live issue), and (b) the final disposition of the point should await Module II where the s.146B amendment and related matters would be determined. Accordingly, the challenge on this ground was dismissed subject to the outcome of Module II.
• Core Ground 2 (noise, amplitude modulation, shadow flicker, reasoned consideration): The court treated most of the complaints as merits‑based and a "scattergun" attack on the planning judgment. The Commission had expressly considered submissions (and the inspector's report records consideration and site inspection); the Applicants had not discharged the evidential onus to show failure of consideration or scientific inadequacy. Claims about reliance on outdated guidance were countered by the Commission's acknowledgement that it had regard to the draft 2019 guidance as well as the 2006 guidelines. On shadow flicker and AM, the Court observed that the EIAR addressed these matters, the inspector analysed them and conditions and mitigation (including the developer's commitment to zero shadow flicker measures and requirement for monitoring/mitigation) were imposed. The complaint that the Commission failed to engage the HSE or third parties on responses was held to be unparticularised and effectively a merits complaint or an unlawful attempt to impose procedural obligations not required by EU law.
• Core Ground 4 (inadequate plans/particulars for battery/substation/haul route): The court found the pleading was insufficiently particularised and did not identify a material shortcoming. The EIAR and annexes described the substation/battery and haul route provisions and the inspector had addressed these matters; in any event some components were identified as to be applied for subsequently and had been assessed cumulatively in the EIAR.
• Core Ground 5 (EIA portal / public access to documents): The court held that the complaint conflated responsibilities — the Minister, not the Commission, bears responsibility for the central EIA portal under the domestic scheme; the Applicants had not joined the Minister and their pleadings lacked specifics about any prejudice arising from alleged non‑publication. The ground therefore failed on pleading and on the merits in relation to the Commission.
• Core Ground 6 (EIA dimension of Core Ground 2): The Court treated this as derivative of Core Ground 2 and concluded that nothing additional was established by recasting the noise/shadow flicker complaint as an EIA breach; the same evidential deficiencies applied.
• Core Ground 7 (project splitting): The court applied EU jurisprudence on the "project as a whole" and cumulative/in‑combination effects. It concluded that the EIAR had addressed cumulative effects and that the Applicants had not shown project‑splitting or a material omission in the EIA assessments.
• Core Ground 8 (reasonable alternatives): The court cited Holohan and explained that the developer is required to supply an outline of the main alternatives and an indication of reasons for the choice. The court found that the EIAR and annexes contained adequate material on alternatives and that the Applicants had not discharged their evidential burden to show inadequacy.
• Core Ground 8A / Validity Ground (regulations): The constitutional/validity challenge to article 214(1) of the Regulations (landowner consent requirement) was modularised to Module II and therefore not finally determined in Module I.

Holding and Implications

Holding: The court ordered that the proceedings be dismissed insofar as they concerned Module I (i.e. all grounds other than the balance of core grounds 1 and 8A). In the court's words, the proceedings were dismissed "insofar as concerns Module I (grounds other than the balance of core grounds 1 and 8A)".

Key implications and immediate effects:

• Module I Disposal: Core Grounds 2, 4, 5, 6, 7 and 8 were dismissed for the reasons summarised above. Core Ground 3 was withdrawn by the Applicants. The court found that these grounds were either merits complaints, inadequately pleaded, or not supported by the required evidential material (especially expert evidence on technical/scientific matters).
• Core Ground 1 and Core Ground 8A (Module II): Core Ground 1 (landowner consent) and the validity challenge to article 214(1) (Core Ground 8A) were modularised to Module II and will be decided in tandem with the related issues in the second set of proceedings (the s.146B amendment). The court expressly preserved and deferred those matters for the Module II hearing (scheduled for continued consideration and final disposition together with consequential directions).
• Costs: The court made provisional directions on costs: subject to any contrary written legal submission in due course, there was to be no order as to the Applicants' costs in Module I, and the opposing parties' costs were reserved. The judgment clarified that any existing costs protection the Applicants had would not be diluted by the court's provisional approach and that further debate on costs would await the outcome of Module II.
• No new precedential expansion on environmental law beyond applying established principles: The court applied established domestic and EU jurisprudence (including Holohan and Altrip jurisprudence on harmless error and EIA) but did not create new legal tests. The decision illustrates the court's insistence on evidential particularity for technical environmental complaints and on the utility of modularisation for complex planning litigation.

Final Disposition

ORDER:

• The proceedings are dismissed as to Module I (all grounds other than the balance of core grounds 1 and 8A).
• Core Ground 1 and Core Ground 8A are to proceed to Module II for final determination (the court referenced related proceedings and a section 146B amendment in that context).
• Subject to any further written submissions on costs, there is to be no order as to the Applicants' costs for Module I and the costs of the opposing parties are reserved; perfection of the order is postponed pending outcome of the final module.

Note: This summary is strictly confined to the material and reasoning contained in the court's written judgment as provided. Where the judgment deferred or modularised issues, this summary records that procedural outcome and does not speculate on matters reserved for subsequent determination.