LONDON (Reuters) - The share of global emissions subject to carbon pricing policies is on course to rise to around 33 percent in 2035 from about 8 percent last year, the International Energy Agency (IEA) said in its 2013 World Energy Outlook on Tuesday.
Pricing carbon is aimed at encouraging energy producers and industry to switch to greener energy and away from burning fossil fuels.
As well as the European Union's current Emissions Trading Scheme (ETS), the IEA said it expected China to launch carbon pricing for all sectors of its economy starting in 2020.
The world's biggest greenhouse gas emitter, China is due to start seven regional pilot carbon markets by 2015 and is designing a nationwide scheme to be deployed later in the decade.
Prices on the EU ETS are expected to rise from an average of $10 per ton of CO2 emitted in 2012 to $20 in 2020 and $40 in 2035, the IEA said.
It said it expected China's CO2 price would start at $10 per ton in 2020 and rise to $30 per ton in 2035.
From 2015, the IEA expects all investment decisions in the power sector in the United States, Canada and Japan to include an "implicit" carbon price to promote the development of low-carbon technologies.
The IEA, which advises large industrialized nations on energy policy, has warned of a 20 percent rise in emissions from energy production between 2020 and 2035 unless governments introduce new policies.
"There is a growing disconnect between the greenhouse gas emissions trajectory that the world is on and one that is consistent with the 2 degrees Celsius climate goal," the IEA report said.
Scientists argue it is important to cap temperature rises at 2 degrees Celsius above pre-industrial levels to avert the most devastating consequences of climate change.
(Reporting by Ben Garside; editing by Jason Neely)