Clarksons Platou Securities is tipping a big fall in laid-up platform supply vessels (PSV) as a buoyant North Sea market basks in an "endless summer."

Turner Holm, managing director of equity and credit research, and analyst Sven Sele, said the sector is "unseasonably strong", with 2019 the strongest first quarter for spot rates since 2014.

On Tuesday, the 4,200-dwt PSV NAO Thunder (built 2013) was reported fixed at £20,000 ($26,145) per day for two weeks of supply duties by Team Marine, according to broker Westshore.

PSV utilisation stands at 90%, its figures show.

Clarksons Platou said average North Sea rates over the first 15 weeks of 2019 are up 56% compared to the same period last year.

Term contract rates of more than 30 days have reached $18,000 per day in the UK and $21,000 per day in Norway for large modern vessels, it added.

PSVs are seeing a "significant increase in demand", while the number of stacked ships has fallen to 59 from 79 year-on-year, it said.

"Despite reactivations, the North Sea market continues to see low spot availability in the UK and Norway," it added.

And the analysts are expecting rates to rise further as summer demand increases.

"There are already more contracted floating rigs for the summer this year than last year, with potential for more into the summer season, and more rigs contracted for winter 19/20 versus winter 18/19," they said.

Layup list to shrink

"Demand for PSVs has increased by 21 and 26 vessels from March to September in 2017 and 2018, respectively."

And they added: "The same increase this year could absorb the relevant fleet of stacked vessels in the North Sea."

Westshore lists 41 PSVs out of action in North Sea ports.

Day rates in other regions have been picking up and making work in Africa, the Med and certain other regions more attractive, Clarksons Platou believes.

Oil and gas companies are increasingly willing to pay mobilisation for vessels, which has been rare.

Through to the end of May, 14 ships will have left the North Sea, while none is scheduled to enter the market.

Clarksons Platou also said stock prices look attractive and should react to the movement in rates.

Implied values in Norwegian PSV investor SD Standard Drilling "illustrate discount pricing compared to 2017 vessel acquisition prices," the analysts said.

In the US, Tidewater is trading at a 30% discount to estimated second hand values despite a robust balance sheet.

And they added: "With a strong fleet and financial runway, we see Nordic American Offshore as an attractive levered bet on a rapidly rising market."