PARIS, April 19 (Reuters) - SLN, the New Caledonian nickel producer controlled by Eramet, announced on Tuesday plans to hire a floating power unit for its smelter to cover its needs pending the replacement of the Pacific territory's ageing central power plant.

Improved energy supply has become a priority for SLN as it tries to turn around its operations after losses in recent years linked to high costs and social unrest.

The issue has become more urgent after an accident last year caused one of the units of New Caledonia's main power plant to close, leading SLN to rely on costlier top-up purchases from the rest of the local network, it said.

SLN is to hire for three years a floating installation from Turkish-based specialist Karpowership, which will provide the 180 megawatts required to power its Doniambo smelter, the company said in a statement.

The temporary power unit will burn fuel oil like New Caledonia's central plant but its more efficient technology will cut carbon emissions by about 30% compared with current levels, SLN said.

Subject to regulatory approval, SLN aims to have the floating installation connected to its smelter in August.

The three-year contract is intended to cover the period until the first phase of New Caledonia's future power plant - due to be based on renewable energy sources - is launched in 2025.

Energy infrastructure is among constraints facing New Caledonia as it looks to use its large nickel reserves to tap into booming demand for the metal in electric vehicle batteries. (Reporting by Gus Trompiz Editing by Mark Potter)