Iran Conflict and the Global Energy Security Equation

A major international energy summit went ahead in Riyadh from Sunday despite an attack on the city's King Khalid International Airport that killed 12 people and wounded 309, according to Saudi Arabia's General Authority of Civil Aviation.

Saudi Arabia's Ministry of Energy said the 25th World Petroleum Council Energy Congress opened in Riyadh. The 17th International Energy Forum (IEF) Ministerial Meeting will be held on the sidelines of the gathering, dubbed Riyadh Energy Week, which runs through Thursday.

Italy, however, which co-chairs the IEF, will take part by video link. Nigeria, the other co-chair, is sending representatives in person.

The IEF brings together 68 countries that account for more than 90 percent of global oil and gas supply and demand, with members including Saudi Arabia, the United States and Russia. The meeting is taking place as the US-Israel war with Iran disrupts energy flows, forcing governments to reassess their energy security.

Here is a look at the global energy picture, the role of the Middle East and which countries hold strategic reserves.

Where does the world's energy come from?

Energy heats homes, powers vehicles, provides light and runs factories that make goods. It comes from fossil fuels such as oil, coal and gas, alongside nuclear power and renewables.

Despite the rapid growth of renewable energy, fossil fuels still account for nearly 81 percent of global energy consumption. Oil is the largest source at 31.4 percent, followed by coal at 25.9 percent and natural gas at 23.5 percent. Traditional biomass, nuclear power and other sources make up the rest.

Production is concentrated in a few regions, so disruption anywhere ripples across global markets. The Middle East is the largest oil-producing region, North America leads in natural gas, and Russia and Central Asia are major producers of both.

How does Middle Eastern energy reach the world?

The Middle East's importance to energy markets also lies in its geography. Three narrow maritime corridors connect producers in the region with consumers worldwide.

Before the Iran war, about 27 percent of global seaborne oil trade and nearly 20 percent of liquefied natural gas trade passed through the Strait of Hormuz at the eastern edge of the Arabian Peninsula. To the west of the peninsula, the Bab al-Mandeb strait links the Red Sea to the Gulf of Aden, while the Suez Canal connects the Red Sea to the Mediterranean.

As the Iran war spread to other parts of the Middle East and Yemen's civil war escalated, traffic through both the strait and the canal fell, forcing some energy shipments to take the longer route around Africa.

Richard Matthews, director of consultancy and research at Gibson Shipbrokers, a London-based shipping brokerage and maritime advisory service, said: "This is perhaps the first time we have really seen a serious narrowing of a chokepoint."

He told Al Jazeera that what sets the Strait of Hormuz apart from other chokepoints is that "there is no alternative sea route. There are some pipelines, but there is no alternative option, which is why it has become so important in terms of cargo volumes."

Gulf ports are where much of the region's energy begins its journey to the rest of the world.

Which countries depend most on Middle Eastern oil?

At the end of the supply chain, people and businesses are feeling the disruption through higher prices for essentials. Countries that rely on oil, gas and fertiliser from the Gulf face higher prices, longer waits for shipments and the need to find alternative suppliers. Even when deals keep goods moving, the added costs are passed down the supply chain.

Eritrea and Madagascar are the most dependent on Middle Eastern oil, each drawing about 90 percent of their supply from the region. They are followed by Pakistan (78 percent), Japan (77 percent) and Kenya (77 percent).

Which countries depend most on Middle Eastern gas?

Gas is even harder to replace than oil because most of it is shipped as liquefied natural gas from Qatar and the United Arab Emirates through the Strait of Hormuz.

Countries that depend on those shipments are paying more for fuel and electricity and competing for increasingly scarce cargoes. Poorer importers with less storage capacity are struggling most to find alternatives.

The countries most reliant on Middle Eastern gas are mainly in Asia. South Korea draws 31 percent of the gas it uses from the region, followed by India (29 percent), Pakistan (27 percent) and Taiwan (26 percent).

Who holds the largest emergency oil reserves?

Countries keep emergency oil stocks for times when supply is cut off, and this is the world's main buffer in the war. That buffer is now thinning.

Energy industry leaders warn the West has very little left to release, and the US Strategic Petroleum Reserve is at its lowest level since 1982.

Amin Nasser, the head of Saudi Aramco, said at the Energy Intelligence Forum in London on Monday: "Estimates show there are now fewer than 6 billion barrels of commercial inventories, most of which is not really available."

The International Energy Agency (IEA), which coordinates emergency reserves for its members, released a record 400 million barrels of oil in March. It is preparing to release another 100 million barrels of crude and diesel to cool soaring diesel prices, though part of that may be oil from the March release that has yet to reach the market.

A storm in the Gulf of Mexico and attacks in Saudi Arabia are once again threatening supply, keeping oil prices above $100 a barrel.

Before this year's releases, China held the largest reserves at an estimated 1.4 billion barrels, more than the rest of the list combined. The United States was second with 413 million barrels, followed by Japan with 263 million barrels.