The body's World Energy Outlook shows wind accounting for 7.5% of the world's power by 2035, up from its prediction last year of 7.3%, with 2,680TWh produced. In 2011, 438TWh was produced by wind power.
Around 80% of the additions are expected to be onshore, although the report predicts that offshore wind installations "will gradually increase in importance".
The IEA said the global average investment cost for onshore wind in 2012 was about $1,700/kWh, with offshore coming in between $3,000/kWh and $4,500/kWh. The onshore wind figure is expected to fall by 10% by 2035.
While the EU currently has the largest share of total installed capacity, the report shows China with the highest capacity by 2020.
Overall, renewables are expected to provide 18% of the world's energy needs by 2035, up from 13% in 2011. This implies an increase of more than 7,000TWh, making up almost half of the increase in total power generation.
Renewable sources of energy are shown generating the second largest amount of energy before 2015, and closing in on coal as the primary source by 2035.
Almost two thirds of this increase is to come from non-OECD countries, the report finds.
To achieve this sea change, cumulative investment of $6.5 trillion is needed before 2035, with renewables accounting for 62% of investment in new power plants.
Subsidies are expected to more than double to $220 billion a year by 2035, from $101 billion in 2012, already up 11% on the year before.
Conversely, the IEA pressed the need to reduce subsidies on fossil fuels, which were five times higher than those for renewables at $544 billion.
The subsidies are characterised as holding back the fight against climate change and disproportionately benefitting the wealthy, rather than, as some have claimed, the disadvantaged.