The government has been accused of undermining efforts to achieve the targets set for offshore wind energy in the Climate Action Plan.
Wind Energy Ireland has warned that the government's radical change in policy has created massive levels of uncertainty among international investors and the global supply-chain.
This week, the Cabinet approved plans to accelerate delivery of 5GW of offshore wind by 2030.
The new policy means future offshore wind farms must be built in Designated Marine Areas and will not connect to points on land, but rather to offshore substations.
CEO of Wind Energy Ireland Noel Cunniffe said timelines outlined in the Climate Action Plan will not be met due to the changes announced by government.
"This policy statement is a major change compared to what had previously been communicated to the sector", he told Newstalk.
"It introduces a number of new variables, but particularly it means that these second group of projects must be built in what's called 'designated marine areas."
"Now the government are telling us that they can develop these marine areas within the next nine months, but legal experts are telling us that it will take more likely 18 to 24 months."
The Department of the Environment, Climate and Communications said this managed rollout in designated offshore areas is "geographically aligned with available onshore grid capacity".
"These Areas, which will be designated according to legislative provisions for Designated Maritime Area Plans (DMAPs) in the Maritime Area Planning (MAP) Act, will guide investment and decision-making and will complement the forthcoming network of Marine Protected Areas," it said in a statement.
"This plan-led approach will ensure that development is managed in a planned, strategic and sustainable way. Importantly, it will provide greater certainty for all maritime users as to where development will be situated."
Main image shows wind turbines and powerful sea waves on the coast of County Wexford. Picture by: Bernard Golden / Alamy