A legal challenge to a plan for gas caverns under Larne Lough has failed at the High Court in Belfast.
Campaigners had applied for a judicial review of the decision by the Department of Agriculture and Environment (DAERA) to grant the plans a marine construction licence.
The legal challenge had been brought jointly by campaign groups No Gas Caverns and Friends of the Earth NI.
Mr Justice Humphreys dismissed all seven grounds of the challenge.
The grounds included that it was a "cross-cutting" matter that should have been considered by the NI Executive and that other material laws on environment and climate changes had not been considered.
The project sees seven large gas storage caverns hollowed out underneath the lough by carving out salt layers.
About half a billion cubic metres of natural gas are set to be stored, creating a 14-day buffer during periods of peak demand.
The long-term proposal was to store hydrogen, as a product of surplus wind power generation.
Islandmagee Energy, the firm behind the project, has previously said there would be no long-term damage to wildlife.
The firm said a year-long study indicates a fully-green gas network in Northern Ireland is possible.
After the ruling on Thursday, campaigners said that they were disappointed, but stated "this is by no means the end".
"This is an incredibly disappointing judgement for our environment," Friends of the Earth Northern Ireland director James Orr said.
"The local community have fought so tirelessly against this hugely destructive scheme.
"In the midst of a climate emergency, we should be seizing the huge economic benefits that come from focussing on energy efficiency and renewable power not prioritising more costly and polluting fossil fuel schemes."