* Power supply improves dramatically ahead of election

* Opposition says timing designed to favour ruling ANC

* President denies this, says energy plan is working

JOHANNESBURG, May 13 (Reuters) - South African President Cyril Ramaphosa on Monday rejected opposition allegations that a recent pause in the electricity cuts that have plagued the country for years was due to an election coming up on May 29.

Rolling power cuts imposed by state utility Eskom reached record levels in 2023 and continued in the first quarter of this year, but there has now been no load-shedding, as South Africans call the cuts, for 48 straight days, the longest period for more than two years.

Over the same 48-day period last year, there were power cuts every day, according to data collected by The Outlier, an independent South African publication specialising in public service data visualisations.

The dramatic improvement in power supply has been a talking point in South African media and has led to opposition accusations that the timing was designed to improve voter satisfaction with the governing African National Congress.

The ANC faces its toughest electoral test to date, with opinion polls suggesting it is on course to lose its parliamentary majority for the first time since it came to power 30 years ago at the end of apartheid.

In a weekly newsletter, Ramaphosa said Eskom's improved performance showed that the government's energy plan announced in 2022 was bearing fruit.

"Yet, against all the available evidence, some people have claimed that the reduced load-shedding is a political ploy ahead of the elections," he said. "This is not borne out by the facts."

Ramaphosa attributed the improvement to a renewed focus by Eskom on maintenance, new generation capacity from renewable energy projects and strong take-up of rooftop solar panels boosted by tax incentives.

BURNING DIESEL

The Democratic Alliance, the biggest opposition party, last week attributed the improved power supply to "political interference" by the ANC, which it accused of putting pressure on Eskom to keep the lights on.

"South Africans should not be fooled by this brazen abuse of power and they must act to decisively vote out the manipulators on the 29th of May," it said in a statement on its website.

A particular point of dispute was whether Eskom was burning more diesel to increase supply, as alleged last week by the utility's former CEO, Andre de Ruyter, who is openly antagonistic towards the ANC.

"If the lights are on, well done, but they're on because we are pouring money into diesel at a rate of knots," de Ruyter, who stepped down in February 2023, told a conference in South Africa, in comments widely reported by local media.

South Africa's energy regulator Nersa said on Friday that in April alone, Eskom had generated 168.5 GWh from diesel generators, more than half of the maximum it is normally allowed per quarter.

In televised remarks on Monday, Electricity Minister Kgosientsho Ramokgopa denied that excessive use of diesel-powered turbines was behind the pause in load-shedding.

"Nothing could be further from the truth," he said, accusing Eskom's detractors of attempting "to soil the work that the Eskom team has done ... in its totality from the board to the lowest members of Eskom including the cleaners".

(Editing by Estelle Shirbon, Kirsten Donovan)