Supported by abundant unconventional natural gas and oil reserves, the United States and Canada will become “almost totally energy self-sufficient” by 2030, according to a new forecast by BP plc.

BP’s annual “Energy Outlook 2030,” published on Wednesday, in many respects doesn’t veer too far from last year’s report. The oil major’s economics team found that natural gas would continue to be the fastest growing fossil fuel worldwide, with demand rising by about 2% a year. Renewables, however, are predicted to grow at a faster rate than predicted a year ago, rising by an annual rate of around 8%.

North America’s unconventional natural gas and oil fields also are exceeding expectations, which will change the global energy picture, said CEO Bob Dudley. The ability to become nearly self-sufficient in energy over the next two decades holds big implications for global security, he said.

“Our report challenges some long-held beliefs,” he said in presenting the report. “Significant changes in U.S. supply and demand prospects, for example, highlight the likelihood that import dependence in what is today’s largest energy importer will decline substantially.”

The outlook for North American natural gas and oil supplies was revised higher because of the “evolving expectations for shale plays.”

“The growth of unconventional supply, including U.S. shale oil and gas, Canadian oilsands and Brazilian deepwaters, against a background of a gradual decline in oil demand, will see the Western Hemisphere become almost totally energy self-sufficient by 2030,” said BP chief economist Christof Ruhl, who oversaw the report. “This means that growth in the rest of the world, principally Asia, will depend increasingly on the Middle East in particular for its growing oil requirements.”

According to BP, shale gas and coalbed methane are forecast to account for 63% of North American production by 2030. “Sustained growth of shale gas” also raises the prospect for up to 5 Bcf/d of liquefied natural gas (LNG) exports from North America by 2030.

Oil is expected to continue to lose market share to 2030, even though demand for hydrocarbon liquids still is expected to reach 103 million b/d, up by 18% from 2010. According to BP, the world still would need to bring on enough liquids — oil, biofuels and others — to meet a forecast of 16 million b/d of extra demand by 2030 and replace declining output from existing sources.

The volume of oil imports in the United States by 2030 is predicted to fall below 1990s levels, mostly because of rising domestic unconventional oil production and because ethanol is replacing crude.

China is set to leapfrog the United States to become the biggest energy importer, according to BP. Overall global energy demand is expected to surge in the next two decades because of economic and population growth in China and India. By 2030 China and India are expected jointly to account for about 35% of global population, gross domestic product and energy demand.

Because of its growing abundance and lower emissions during power generation, gas will continue to be the fastest growing fossil fuel, according to BP.

“Natural gas is a sustainable option being deployed at scale,” Dudley said. “Gas typically generates fewer than half the emissions of coal when burned for power. It is not by accident that gas is growing so fast in the U.S., perhaps the world’s most open and competitive upstream environment.”

According to BP, there was 6,609 Tcf of proved gas reserves worldwide in 2010, “sufficient for 59 years of production at current levels. Unconventionals remain to be appraised in detail globally, but current estimates run up to twice this reserves/production ratio.” Fossil fuels continue to dominate to 2030 and should account for 81% of global demand by 2030, which would be 6% below current levels, BP noted.

BP’s report highlighted advances in energy-related technology, which it said has contributed to efficiency gains and increased resources worldwide.

“Technology underlies many of the trends apparent in this report. For example, the supply of gas has been accelerated as a result of technologies that unlock shale gas and tight gas. In the transport sector, we believe the efficiency of the internal combustion engine is likely to double over the next 20 years. And that will save roughly a Saudi Arabia’s worth of production. By 2030 we expect hybrids to account for most car sales and roughly 30% of all vehicles on the road.”

Fuel switching is predicted to increase, with more natural gas and renewables use at the expense of coal and oil. The gradual switch “should see renewables, including biofuels, continue to be the fastest growing sources of energy globally, rising at an annual clip of more than 8%, much quicker even than natural gas, the fastest growing fossil fuel at about 2% a year over the period to 2030,” said the report.

“This report is by turns challenging, fascinating and stimulating for anyone in the energy business,” said Dudley. “It helps us to be both realistic and optimistic. It shows there are things we can’t change — like the underlying drivers of energy demand — and things we can change — like the way we satisfy that demand. The main message is that we need to have an open, competitive energy sector, which encourages innovation and thereby maximizes efficiency in order to enjoy energy that is sufficient, secure and sustainable into the future.”

BP’s annual update presents the company’s view of the “likely” path of global energy markets to 2030 and the latest report takes into account developments in the past year. Dudley noted that the underlying method remains unchanged in that the company makes assumptions on changes in policy, technology and the economy, based on extensive internal and external consultations, and uses a range of analytical tools to build a “to the best of our knowledge” view. The outlook supplements BP’s “Statistical Review of World Energy,” which is scheduled to next be published in June.

In the liquids sector, global supply growth by 230 “will match expected growth in demand with OPEC accounting for 70% of incremental supply; the group’s market share will approach 45%, a level not reached since the 1970s.” OPEC natural gas liquids growth is forecast to be up by more than 4,000 b/d, driven in part to “rapid growth of natural gas production.”

Liquids supply from the Americas over the next 20 years is predicted to expand by 8,000 b/d, “as advances in drilling technologies unlock additional resources in the Canadian oilsands (plus 2,200 b/d), Brazilian deepwater (plus 2,000 b/d), and U.S. shale oil (plus 2,200 b/d). In addition, the U.S. and Brazil contribute over half of total biofuels production growth (of plus 3,500 b/d) expected by 2030.”

Import dependency, measured as the share of demand met by net imports, increases for most major energy importers — except the United States. Countries now importing energy would need to import 40% more than they do today, but the experience will vary by region, BP found.

“In North America, efforts to reduce dependence on foreign supplies should show impressive results in the next couple of decades. Bolstered by supply growth from biofuels as well as unconventional oil and gas, North America’s energy deficit will turn into a small surplus by 2030.” The share of imported oil demand and the volume of oil imports in the United States is predicted to “fall below 1990s levels, largely due to rising domestic shale oil production and ethanol displacing crude imports.”

Natural gas is projected to be the fastest growing fossil fuel globally, rising by about 2.1% a year. Demand is seen growing fastest in undeveloped countries in Asia (4.6%) and the Middle East (3.7%). Gas is predicted to grow rapidly in China (7.6%) to a level of gas use in 2030 (46 Bcf/d) equal to that of the European Union in 2010. China is expected to contribute 23% to the global demand increase, with the shale of gas in China’s primary energy consumption expanding to 9.5% from 4%.

LNG represents a growing share of gas supply by 2030, according to BP. Global LNG supply is projected to grow 4.5% a year to 2030, more than twice as fast as total global gas production (2.1% a year) and faster than interregional pipeline trade (3% a year). LNG is predicted to contribute 25% of global supply growth from 2010 to 2030, compared to 19% for 1990-2010.

“Of the major sectors globally, growth is fastest in power (2.4% per year) and industry (2.1%) — consistent with historical patterns,” said BP. “Natural gas use in transport is confined to 2% of global gas demand in 2030, despite growing four times from today’s level.”