The World Energy Council called for global action on what it refers to as the energy "trilemma" -- affordability, accessibility and environmentally sustainable energy for all.

The triennial World Energy Congress, based in London, opened Monday in Daegu, South Korea, under the theme "Securing Tomorrow's Energy Today," with more than 6,000 delegates from 113 countries and more than 50 government ministers.

WEC Chairman Pierre Gadonneix, in a statement on the eve of the meeting, cited key factors since the last congress in Montreal in 2010, which prompted many countries to re-evaluate their energy strategies, including the financial crisis, the development of unconventional hydrocarbons and Japan's Fukushima nuclear power plant disaster in 2011.

"It is vital that we form a coherent, long-term framework within which to plan and implement future investment," Gadonneix said. "Leadership is needed if we are to address the triple challenge of the energy trilemma, affordability, accessibility and environmentally sustainable energy for all."

Energy demand will continue to increase and double by 2050, mostly driven by economic growth of countries that are not part of the Organization for Economic Co-operation and Development, WEC says.

Because of new fossil fuel discoveries and extraction technologies, fossil fuel reserves have more than quadrupled since the last congress in 2010 and the WEC says that trend will continue, noting "there is no shortage in sight" of fossil fuel resources.

Asia will have the biggest need for investment in energy infrastructure until 2050 -- an estimated $10 trillion to $12.5 trillion, compared to $3 trillion to $4 trillion for Europe or North America, the council says.

Speaking at the opening of the congress, Khalid al-Falih, president and chief executive of Saudi Aramco, whose state-run company ranks first among oil companies worldwide in terms of crude oil production and exports, said there was no need for concern regarding supply.

"I was hoping that by now there would be more realization that there is security of supply, that there are multiple supply sources of all kinds of petroleum and that the concern and the hype about energy security would be reduced," Platts quoted al-Falih as saying.

Instead, he said, there were "shortages in investment across the value chain -- and in many cases the investment shortages are actually in consuming countries."

As for renewable energy, al-Falih said as costs come down, the long-term role of renewables was "indisputable."

"Let me also dispel any notion that the petroleum industry views these sources as competitors or displacers of demand," the Saudi Aramco chief said, adding Saudi Arabia aims to become a global solar hub and the kingdom is investing heavily in solar energy.