(Reuters) - Carbon dioxide emissions from energy sources will rise until 2030, when they will level off as fuels such as natural gas replace dirtier supplies of coal, Exxon Mobil said on Thursday.
That forecast, part of Exxon's annual global outlook that stretches out to 2040, calls for total energy demand to rise by 30 percent over the next three decades, with fossil fuels such as oil, natural gas and coal contributing 80 percent of the supply.
More than 90 percent of this fuel demand growth through 2040 will come from China and other developing countries.
Emissions of carbon dioxide, the gas widely blamed for climate change, are already falling in North America, Europe and other developed economies, the company said, and China, the world's largest emitter, is expected to follow the same path eventually.
"China's emissions are expected to begin declining after about 2025, ending decades of very large increases associated with rapid economic development and industrial activity," the oil giant said.
Electricity demand will be the main growth driver for world energy consumption, jumping 80 percent from 2010 levels, while commercial transportation will also push use of liquid fuels higher, Exxon said.
Demand from private vehicles, however, would be curbed by a steep increase in fuel efficiency, the company said, largely based on expectations that hybrid cars will make up 40 percent of that market in 2040 versus about 1 percent now.
Demand for natural gas, which has been Exxon's biggest investment focus in recent years, will rise by 60 percent in 2040 from 2010 level, the company said.
"By 2040, Exxon expects natural gas to account for 30 percent of global electricity demand," William Colton, Exxon's vice president for corporate strategic planning, told a news conference.
The projected 80 percent increase in electricity usage will be offset somewhat by the efficiency improvements in power generation, which will boost demand for all power-generating fuels by a more modest 45 percent.
Coal demand will peak in 2025, and even China, which uses about 50 percent of the world's coal currently, will see its consumption fall by more than 10 percent by 2040.
Much of that shift away from carbon-intensive coal sources will be driven by the rising costs of carbon dioxide emissions, which Exxon said would likely be near $60 per ton in most developed economies.
That is about six times more expensive than carbon emissions currently cost in Europe.
Exxon also remained pessimistic about the growth of renewable energy, forecasting that wind, solar and biofuels will account for only 4 percent of global demand in 2040.
Oil and natural gas will make up 60 percent of the global demand in 2040, up from about 55 percent today.
Exxon, the world's largest publicly traded company, has poured more than $125 billion into oil and gas projects over the past five years largely to tap into shale rocks, oil sands and Arctic regions that were once too difficult to reach.
(Editing By Andre Grenon)