Only able to travel at 14-15 knots rather than the normal 18 knots
The Ben-my-Chree is currently having to operate its engines at less than half its usual capacity.
It's because of energy efficiency restrictions that have been placed on the vessel.
The treasury minister has been responding to a question in the House of Keys.
Dr Alex Allinson says its hoped the impact on sail times - if it was needed - would be minimal:
DoI 'carried out inadequate searches' in response to FoI
Bowel cancer awareness campaign returns with Island-wide initiative
Ravens face second game in three days
"Rough start" for Green Lounge amid travel disruption and fuel concerns
Hundreds take part in Easter charity motorbike ride for Hospice Isle of Man