When the world's second largest publicly traded company by market capitalization speaks, it's worth listening to. While ExxonMobil (XOM -3.16%) investors probably pay attention to the headline numbers when Exxon reports quarterly earnings, the company also has a lot to say about the future of global energy. In that vein, here are some fascinating things you probably didn't know about what the next thirty years has in store for oil, according to the biggest energy company in the world.

Oil's demise is greatly exaggerated
Over the past few years, much has been made of oil's imminent replacement as the world's primary source of energy. Fossil fuels, as the arguments contend, are the energy sources of the past. The future will be shaped by natural gas and nuclear energy, as well as renewables such as wind and solar.

In ExxonMobil's estimation, that couldn't be further from the truth. Between 2010 and 2040, ExxonMobil predicts oil demand will actually continue to grow, at a compound annual rate of 0.8% to nearly 225 quadrillion BTU's. And while ExxonMobil believes natural gas and renewables, including wind and biofuels, are viable and will in fact see demand increase at higher rates than oil, no other energy source comes close to replacing oil as the world's main source of energy demand on an absolute basis.

A major contributing factor behind oil remaining atop the global list of energy sources is the fact that technological developments are enabling safe and relatively easy location and production of what were, in the past, extremely difficult-to-produce resources. For evidence of this, look no further than the boom in offshore drilling, particularly in deepwater and other harsh environments.

Technological advancements are key for future oil production
Rapid technological developments have all but nixed the theory that since supplies of oil are becoming harder to find, the world will be forced to focus on alternative sources of energy.

Drillers themselves have nothing but great things to say about the future of oil drilling, even in locations that just a few years ago would have been extremely prohibitive to offshore drilling. Offshore rig producer Transocean (RIG 1.57%) has dramatically shifted its business toward what it terms 'high-specification rigs' to meet the ever-increasing challenges from difficult drilling environments. The company's core asset portfolio going forward will be centered on harsh environments, high-specification jack-ups, and ultra-deepwater rigs.

And, there's plenty of evidence that suggests Transocean's vision is entirely accurate. Of all new field resources discovered in 2012, 12 billion barrels of oil equivalent were discovered at depths of 5,000 feet or greater. This compares to slightly more than 6 billion barrels of oil equivalent discovered at depths between 1,300 and 5,000 feet, and just over 3 billion discovered at depths of less than 1,300 feet.

Booming populations present new geographies for investment
As emerging markets continue to develop, middle classes expand and will soon have hundreds of millions of new entrants. One such geography ExxonMobil pinpoints for future development is Africa, and if the company's projections hold true, it will soon be a global leader in energy demand.

According to Exxon, Africa's population over the next three decades is expected to grow by 800 million people, making it the fastest-growing geographic region in the world. Not surprisingly, Exxon has major investment plans in store for Africa. Of its major project start-ups between 2012 and 2017, Exxon is developing deep-water satellites in Angola as well as conventional plays in Nigeria, which should capitalize on both African oil development and the previously mentioned boom in offshore activity.

Exxon isn't the only oil major targeting Africa for future growth. France-based Total (TTE 0.95%) already produces more than 700,000 barrels of oil equivalent per day in Africa, and its operations in the continent will only grow going forward. Total has more than 7 billion euros in gross capital expenditure plans for Africa, far ahead of its next largest geographical area of investment, which is Europe, at just under 6 billion euros.

The bottom line
Put simply, oil isn't going anywhere. Other forms of energy will indeed remain a part of the global energy mix going forward, but there's no escaping the fact that as the world's population grows, particularly in the emerging markets, so too does the unquenchable thirst for oil. As a result, ExxonMobil, Transocean, and Total will profit handsomely from oil's continued dominance atop the global energy mix.