The head of Eirgrid says nobody should prejudge which is the right option when it comes to the Grid West project.
The company will be outlining a proposed underground route for the power line from Roscommon to Mayo today.
It has already submitted an overground pylon plan, which is set to cost €240m.
Eirgrid says they are still looking at the cost for the alternative.
Chief Executive Fintan Slye says they want to take the public concerns into account.
"This is about responding to what the public said to us and what we learned through the consultation period that we did," he said.
"One of the key pieces of feedback we got was that the underground option didn't get the depth and breath of analysis and consideration that it should have done.
"So what we're doing now is setting that out side-by-side and I don't think any of us should pre-judge what the right answer is."