Opec's annual World Oil Outlook report says that the upstream sector will require $11 trillion in investments between 2018 and 2040.
"It is vital that as an industry we ensure there is timely and adequate investment so as not to lead to a supply shortage in the future," the report noted.
The report found that energy demand will increase from 274 million barrels of oil equivalent per day (mboe/d) in 2015 to 365 mboe/d in 2040. Opec countries will see growth from 20 mboe/d in 2015 to almost 33 mboe/d in 2040.
Oil demand growth will slow over time, with demand reaching 104.5 million barrels per day by 2023, 7.3 mb/d higher than 2017. Oil demand growth will be driven by the petrochemical sector, while other industries, including iron and steel, glass and cement production, construction and mining, will see strong competition from alternative fuels.
Meanwhile, tight oil supply will make up 15% of global liquid output at its peak in the late 2020s, most of which will come from the US.
Natural gas has the largest estimated demand grow, and is expected to account for 25% of the global energy mix by 2040. Still, oil is expected to remain the largest contributor to the energy mix, at 28% by 2040. The total fossil fuel share of the energy mix in 2040 is estimated at 75%, a 6% drop from 2015.
Out of an expected 442 million commercial vehicles by 2040, around 370 million will remain conventional. Natural gas vehicles will account for 6% of the commercial fleet by 2040, and electric vehicles will reach a high of 4% of commercial vehicles in 2040.
Post-2025, global crude exports are expected to increase gradually to levels just below 43 mb/d, driven by increasing demand from the Asia-Pacific and increasing exports from the Middle East. Middle East crude exports are seen to increase by more than 6 mb/d between 2025 and 2040.