The Niue government says in recent weeks power use has surged by up a third and more rationing is possible.
Issues with the generators which left the island without power for a week were fully overcome by last Saturday local time, after an engineer had flown up from New Zealand.
But the Infrastructure Minister, Crossley Tatui, said the government still wants the public to be vigilant in conserving power.
He said the island's normal load is about 600 kilowatts but with current weather conditions and intense heat, there has been a surge in demand, of up to 800 kilowatts.
The minister said the island's four generators can generate up to 810 kilowatts, after storms late last year damaged battery storage and solar energy output.
However, one of those generators is in New Zealand undergoing repairs.
Niue Utilities told Niue Broadcasting (BCN) that this repair work is placing considerable strain on the system due to high demand.
Consequently it said rationing measures are needed because the load is exceeding the current capacity.
The director of Utilities, Clinton Chapman, said the island has to make do with what it has, until the repaired generator is returned.
He also said they are working with Tesla and hoping to bring a team to the island soon to get the battery storage system back on line.
Meanwhile, Tatui said the island's new power house is set to be opened in March.
The minister also warned the people to be ready for more rationing.