Thanks to the advent of hydraulic fracturing, natural gas has a new manifest destiny: By 2040, the commodity used to make electricity will command 25 percent of the world’s energy supply.

At least, that’s what Exxon Mobil Corp. projects.

Natural gas “is penetrating into the power sector, which has been predominantly coal in the past. We see it making tremendous inroads there,” said Lynne Lachenmyer, a senior vice president at Exxon Mobil, at a petrochemical conference in Pasadena on Thursday.

The oil and gas behemoth expects that in 30 years, natural gas will overtake coal as the second-most used energy source after oil, as demand for the commodity climbs 65 percent over that period, she said.

“We see a lot of people looking at natural gas as a form of transportation fuel, so you’re beginning to see compressed natural gas or liquefied natural gas applications for fleets within large communities,” she said. “Its growth rate is higher than the balance of the energy mix, so it’s basically increasing its market share on an annual basis.”

Surrounded by engineers, bankers and Port of Houston officials at the 2013 Petrochemical and Maritime Outlook Conference, Lachenmyer said even as solar and wind pick up steam as sources of energy, fossil fuels aren’t going anywhere.

Wind power is expected to grow by 7 percent per year while solar power will be 20 times more prevalent by 2040. Still, wind will make up just 7 percent of the world’s stockpile of energy in that year and solar will make up just 2 percent, Lachenmyer said. Meanwhile, oil and natural gas will make up 60 percent of the world’s energy supply in 30 years, up from 55 percent today, she said.

Population growth and rising economic prosperity will push demand for energy by a third in 2040 – that’s equivalent to the current energy consumption of Russia, India, Africa, Latin America and the Middle East combined.

In the U.S., natural gas is undergoing rapid transformation. Once thought unreachable, massive natural gas resources trapped in dense, shale rock across the country have been unlocked by new drilling technology and a process known as hydraulic fracturing. That, in turn, is creating a new economic force that is disrupting and boosting businesses as diverse as the auto industry, the agricultural sector and the petrochemical industry.

“This growing supply of shale gas and its associated gas liquids have really allowed North American petrochemical producers to have a significant cost advantage over other producers in the world,” Lachenmyer said.

That promises to be a boon for the Port of Houston, where the petrochemical industry and the export business have formed a symbiotic relationship. Just five years ago, before the shale revolution, petrochemical exports were declining, and the U.S. nearly became a major importer of petrochemical products.

So far, more than 120 petrochemical construction projects have been publicly announced in recent years, promising $80 billion in investments throughout the U.S. Gulf Coast region.

Once that gets rolling, petrochemical exports are expected to boom, too.

Currently, petrochemical exports make up 12 percent of the overall U.S. exporting business, which brings in $188 billion a year. The American Chemistry Council projects that chemical exports will outpace imports and grow from an $800 million trade surplus in 2012 to more than $46 billion of net trade exports in 2020, she said.

“This improvement in profitability is what’s giving rise to the desire to continue to invest, to grow our footprint here alongside the shores of the Houston port,” she said. “That’s good news not just for the petrochemical industry, but also for the Port of Houston.”