The £14 million MV Alfred was shown off for the first time today at a ceremony in Kirkwall.
The Vietnamese-built vessel will sail between St Margaret’s Hope in Orkney and Gills Bay, near John O'Groats, in Caithness.
It will provide up to two-thirds more car capacity than its predecessor, MV Pentalina.
Pentland competes with Scottish Government-subsidised NorthLink, run by Serco, which operates between Stromness in Orkney and Scrabster in Caithness.
MV Alfred can accommodate 430 passengers, nearly one quarter more than its predecessor's 350.
It can carry 98 cars, or 54 cars and 12 articulated vehicles/coaches.
MV Pentalina could carry 32 cars and 12 of the larger vehicles.
The new vessel boasts a "dog-friendly indoor sun deck lounge" and five other seating areas.
Pentland Ferries owner and managing director Andrew Banks said: “This is the most environmentally-friendly ferry of its kind in Scotland and its low fuel consumption makes it the greenest way to travel to Orkney.
“We’re confident that our passengers will love the high quality of the new facilities and the improved capacity on board.
“We are proud to be bringing this new quality of service to the people of Orkney and to visitors to our islands.”
The vessel was named after Mr Banks’ father.
The operator said it had a wind turbine for feeding power to its offices, shore base and the ship when it is docked overnight.
Pentland, which operates without public subsidy, has complained to the European Commission over ministers awarding a new NorthLink contract to Serco which will include fare reductions.
That led to the Scottish Government announcing last week it would extend the current contract - due to end today - by three months until the end of January, pending resolution of the complaints.
Complaint to EU
Islands minister Paul Wheelhouse said: “We need to engage further with the European Commission about the on-going complaint from Pentland Ferries and resolve any outstanding issues."
“The extension will allow us to conclude that engagement before signing the new contract with Serco NorthLink Ferries, as well as giving ferry users continuity of service in the short term.
“It’s important to stress that will have no impact on the Scottish Government’s commitments around reduced cabin fares and the three year freeze on islander fares.”
This includes islanders paying 20 per cent less for cabin fares on Aberdeen-Kirkwall-Lerwick routes.
These are on top of a 30 per cent discount for passenger and vehicle fares for islanders.