The High Court has overturned a decision by An Bord Pleanála, refusing permission for a proposed gas terminal in Co Kerry.
Shannon LNG wants to construct a power plant, battery energy storage system and a re-gasification unit, on a 630-acre site between Tarbert and Ballylongford.
Last September, the planning board ruled that it would be inappropriate to permit such a development, pending the completion of an ongoing review of energy supply.
An Bord Pleanála said the project was "contrary to Government policy and therefore contrary to the proper planning and development of the area".
However, the High Court has found that this view was based on an interpretation of policy statements and technical analysis, as opposed to a formal State directive or undertaking.
The development follows a judicial review application by Shannon LNG, a subsidiary of the US-based New Fortress Energy company.
The judgment also said An Bord Pleanála failed to consider or have regard to support for the project in the Kerry County Development Plan, along with "relevant considerations" from several other plans, concerning measures to safeguard gas supply.
The decision to quash the refusal is contained in a ruling from Mr Justice Richard Humphreys.
He found that An Bord Pleanála had misclassified a draft consultation document as national policy and had incorrectly factored this as part of its substantive decision.
In addition, it failed to consider a National Risk Assessment policy, adopted after the inspector's report and prior to the An Bord Pleanála's decision.
This was "capable of being assessed as giving additional and recent policy support to the application".
The latest developments come almost 17 years after plans for the development in Co Kerry were first mooted.
They mean that the project can now be remitted - or resubmitted - to An Bord Pleanála for fresh adjudication.
