Local residents have won, "in principle", their Supreme Court appeal over a stay on an order requiring a Waterford windfarm operator to put nine turbines into "standby" mode.
The High Court had previously found they were not built in line with planning permission and required an environmental impact assessment.
However, arising from various factors, the stay will remain in place pending the Court of Appeal's decision on the appeal by Barranafaddock Sustainability Electricity Ltd over the High Court findings concerning the development at Ballyduff.
In important judgments today on the proper approach to be taken to the question of a stay during an appeal in planning proceedings concerning a development requiring an environmental impact assessment (EIA), the Supreme Court allowed the residents' appeal over the stay.
It previously ruled it would not interfere with the stay at this stage for reasons including the Court of Appeal decision on the developer's appeal is pending and the "significant change" in circumstances since the High Court decision of late 2019.
That change relates to the fact that An Bord Pleanála's (ABP) reconsideration of its refusal of substitute consent for the turbines was put on hold pending separate proceedings concerning the substitute consent process.
On July 1 last, the Supreme Court held the substitute consent procedure is inconsistent with the EIA directive.
Giving the main judgment of the five-judge court today on the stay issue, Ms Justice Iseult O'Malley said, "on balance", she would not have granted the stay.
She agreed with aspects of the Court of Appeal ruling on the stay, including the developer had raised arguable grounds of appeal in respect of the effect of ABP's declaration the turbines as built were not exempt development and concerning whether the turbines as built did in fact come within the original permission.
However, the appeals court ruling gave too much weight to the financial loss which might be suffered by the developer by the turbines not operating if it ultimately won its appeal and gave insufficient weight to the public interest in the enforcement of planning law, she found.
The Court of Appeal also gave insufficient attention and weight to the relevant measures and statutory context of the dispute between the parties and to the High Court decision adverse to the development, she held.
In a concurring judgment, Mr Justice Donal O'Donnell agreed with much of the reasoning of his colleague and said he had reached the same conclusion as her, but via a "slightly different" route.
The developer got planning permission in 2011 for turbine structures which became operational in 2015. Because their built height was varied, objectors claimed they were not in accordance with planning approval, while the developer maintained the deviation of the rotor height from 90m to 103m was immaterial in terms of the permission.
After ABP refused to declare the modifications to the turbines was exempt development, the developer brought High Court proceedings. Separately, seven local residents sought an injunction in relation to the status of the turbines as built.
In December 2019, the High Court's Mr Justice Garrett Simons said the effect of the ABP decision the turbines as built were not exempt development was that the developer could not reagitate that question in the court.
He held the altered development was subject to the EIA directive, could only have been lawfully authorised by an application for permission, and the developer was not entitled to rely on an alleged agreement with the local council authorising the extension/change, he held.
Having found the developer had acted in good faith, the judge said, in order to allow an opportunity to regularise the planning status of the turbines, he would not order their immediate removal but instead direct they cease operating.
He put a short stay on the cessation order to allow the developer seek an early hearing of its appeal over his decision, adding the developer could apply to vacate his order if ABP agreed to regularise the situation.
The developer applied to the Court of Appeal on December 20, 2019, for a stay on his orders pending appeal and got the stay that same day.