The world's leading energy officials will meet this week in South Korea to discuss the sector's major challenges, ranging from climate change to the rise of fracking and nuclear power's uncertain future.

The 22nd World Energy Congress begins Monday in the southeastern city of Daegu, which has set its sights on becoming a model for the use of renewable energy, particularly solar.

With over 5,000 participants from 93 countries, the conference, which takes place every three years, is considered the most important meeting of the sector and has been dubbed the "Energy Olympics".

Some 50 ministers and other senior government officials, including many from OPEC nations, as well as bosses of big firms like Tepco, Gazprom, Shell and Aramco are expected to take part.

The future of nuclear energy in the wake of Japan's Fukushima meltdown in 2011 and the rise in North America of shale gas and oil extraction through the controversial extraction method of hydraulic fracturing -- also known as fracking -- are likely to be high on the agenda.

Renewable energy and its uneven deployment across countries will also figure, as governments and industry grapple with the dilemma of how to ensure energy for a growing world population, at an affordable cost, and without aggravating global climate change.

The meeting comes as Japan's government finds itself facing a public increasingly hostile to its use of nuclear power following the Fukushima disaster -- the world's worst atomic accident since Chernobyl in 1986.

Last month Japan shut off its last working reactor for a scheduled inspection with no restart in sight, leaving the country without nuclear power for only the second time since the 2011 earthquake and tsunami, which saw the Fukushima reactors' cooling systems swamped, causing the meltdown.

The catastrophe, which forced tens of thousands around the plant to evacuate, has also cast doubt on a planned nuclear power station in Taiwan over safety concerns on the seismically-active island, with lawmakers now debating its future.

But even as Japan continues to be beset by problems in the ongoing cleanup of Fukushima, including leaking radioactive coolant tanks that have led to contaminated water reaching the sea, the sector is expected to see growth in emerging economies.

China and India are rapidly expanding their nuclear programmes, while energy-starved Bangladesh this month began work on its first plant with Russian technology.

The plant is expected to generate power by 2018 and help ease chronic power shortages that have hit the impoverished country's industry.

The meeting also comes shortly after the UN's climate panel in its most recent report said it was more certain than ever that humans were the cause of global warming and predicted temperatures would rise another 0.3 to 4.8 degrees Celsius (0.5-8.6 degrees Fahrenheit) this century.

Heatwaves, floods, droughts and rising seas are among the threats that will intensify through warming, with UN climate chief Christiana Figueres warning of "an alarm-clock moment for the world".

The projections were based on computer models of trends in heat-trapping greenhouse gas emissions, especially from coal, oil and gas which provide the backbone of energy supply today.

The controversial practice of fracking, meanwhile, has unlocked an energy boom in the United States, but has been banned in other countries over fears of environmental damage, among them polluting underground water reserves and causing earth tremors.

"This is a time of unprecedented uncertainty for the energy sector," said Christoph Frei, secretary general of the World Energy Council.

"Energy demand will continue to increase, driven by non-OECD economic growth, but the pressure to develop and transform the energy system further is immense.

"To make the challenge more daunting, the decisions that policymakers and business leaders must take on our future energy infrastructure are required today."

It is only the second time the congress, which was first held in London in 1924, meets in Asia in a sign of the continent's increasing economic clout and growing energy needs.