Investments in improving energy efficiency must triple this decade if the world is to keep the goal of limiting global warming to 1.5 degrees Celsius (2.7 Fahrenheit) within reach, the IEA said Wednesday.

The investments would allow a doubling of annual gains in energy efficiency to four percent, resulting in a drop in energy demand and fuel consumption that would benefit consumers and provide greater energy security to nations.

The efficiency gains would "deliver vital reductions in greenhouse gas emissions and at the same time create jobs, expand energy access, reduce energy bills, decrease air pollution, and diminish countries' reliance on fossil fuel imports -- among other social and economic benefits," the International Energy Agency said in a report.

The IEA, which advises nations on policy, was hosting Wednesday an energy efficiency conference outside Paris bringing together officials and businesses from over 80 countries.

The agency noted that if existing government policies on energy efficiency were accelerated and fully implemented, that would cover about three-quarters of the necessary effort to double annual efficiency gains.

And while energy efficiency investments are expected to reach record levels this year of over $600 billion, the IEA noted that growth in slowing due to higher interest rates, saying the level needs to reach $1.8 trillion by 2030.

"Often governments don't give (energy efficiency) as much focus as we think they should," the head of the IEA's energy efficiency division, Brian Motherway, told AFP last week.

While increased efforts by governments on boosting renewable production is positive, "we think that we need more of a focus on how we use it", Motherway said.