In the 'Perspectives for the energy transition' report, the agencies outline how the energy system will look in 2050 if the world can limit temperature rise to below 2ºC with a 66% probability.
"The 66% 2ºC scenario would require an unparalleled ramp up of all low-carbon technologies in all countries. An ambitious set of policy measures, including the rapid phase out of fossil fuel subsidies, CO2 prices rising to unprecedented levels, extensive energy market reforms, and stringent low-carbon and energy efficiency mandates would be needed to achieve this transition," IEA said in its findings.
Irena said the expansion of renewables and energy efficiency measures would help meet 90% of the emission reduction needs.
To keep warming to no more than 2ºC above preindustrial levels, Irena said emissions would need to fall to 9.5 gigagtonnes by 2050 from 32 gigatonnes in 2015.
"Total fossil fuel use in 2050 would stand at a third of today's level. The use of coal would decline the most, while oil demand would be at 45% of today's level," Irena predicted.
Irena also believes energy-related CO2 emissions can be completely phased out by 2060.
But it won't come cheap. Irena said overall investment needed to decarbonise the energy sector will require an additional $29 trillion. However, the agency points out this amounts to 0.4% of global GDP.
That investment could boost GDP in 2050 by 0.8%, add jobs and reduce air pollution.