Vienna, Nov 14 (IANS): Despite improved energy efficiency and expenditure on renewable energy sources, the use of fossil fuels globally is expected to remain dominant, an International Energy Agency (IEA) expert said Wednesday here.

Fatih Birol, IEA chief economist and director of Global Energy Economics, made the comments as part of the World Energy Outlook 2013 in Vienna, reported Xinhua.

He said fossil fuel usage amounted to 82 percent of total global energy sources 25 years ago, and that despite financial and other efforts to lower such dependency, the percentage remains the same today.

Birol said the IEA expects CO2 emissions to increase in the next 20 to 25 years which would result in a temperature increase of 3.6 degrees Celsius on the Earth, making the goal of containing the maximum increase to 2 degrees Celsius almost impossible.

Meanwhile, Austrian industry representatives expressed disappointment at European measures to curtail fossil fuel usage.

Austria Press Agency quoted Gerhard Roiss, CEO of oil and gas company OMV, as saying that Europe could be "paying a high price for little effect" and making greater efforts to reduce CO2 emissions, while losing certain parts of key energy-intensive industries to other regions of the world due to rising energy costs.

He added Europe had a clearly defined goal for emissions targets, but none for global competitiveness.

Birol said the US has an advantage in the energy sector due to access to far cheaper shale gas and oil which has reduced its reliance on coal and thereby its CO2 emissions.

He also expressed pessimism at CO2 emissions trading, and said, "don't expect too much of the carbon markets", and Europe must examine whether such a system has a use when economic consequences are taken into account.