Global energy efficiency, or the amount of gross domestic product squeezed from a given unit of energy, improved by 1.8 per cent last year, the International Energy Agency says in a report.
Measures to improve energy efficiency include car fuel economy standards, lighting technologies and building standards.
Despite progress last year, global energy efficiency needs to improve by at least 2.6 per cent a year to put the world on track to meet targets to move away from fossil fuels, the report added.
Countries are under pressure to improve energy efficiency as part of a global agreement to limit global warming which will formally come into effect on November 4.
The more efficient use of energy was more than the 1.5 per cent gain made in 2014 and was triple the annual average rate between 2003 and 2013, the IEA said.
Last year, oil prices weakened substantially. In the United States, the retail price of petrol fell by 38 per cent and inefficient light-duty truck sales reached an all time high of 9.5 million vehicles, the IEA said.
However, fuel economy standards meant that these vehicles were nine per cent more efficient than in 2010. Globally, car fuel economy standards saved 2.3 million barrels a day of oil last year, or 2.5 per cent of global oil supply, it added.
Energy intensity improvements were most marked in rapidly developing countries such as China where it rose by 5.6 per cent last year, up from an annual rate of 3.5 per cent over the previous decade.
"The large emerging economies are moving to centre stage in the clean energy transition and the fight against air pollution, driven by energy efficiency and renewables," Fatih Birol, IEA executive director, said in a statement.
