The Swedish retailer said four large turbines in Carrickeeny, in north west Leitrim, will go into operation next year.
They will generate 25GWh of electricity - the same as would be needed to power 5,500 houses a year.
Joanna Yarrow, of Ikea, said the move would help cut costs, as well as reduce its carbon footprint.
"Companies, individuals or governments - we all have responsibility to address the resource dilemma and commit to a more sustainable future," she said.
"Producing our own affordable, renewable electricity gets us one step closer to becoming completely energy-independent by 2020, while ensuring our commercial success."
Last year, Ikea unveiled its plan to be 100% clean energy-fuelled by 2020.
The sustainability project will see it pump 1.5 billion euros (£1.3 billion) into wind and solar energy sources.
Ikea has two outlets on the island of Ireland: near Belfast's George Best City Airport and in Dublin's Ballymun.
The wind farms in Leitrim will power the stores for the next two decades, the company said.