Ingka Group, which owns most IKEA stores, will by year's end exceed its 2020 target to produce as much renewable energy as the energy it consumes, its chief executive Jesper Brodin has said. 

Ingka Group has spent €2.5 billion over the past decade on wind farms, rooftop solar panels on its stores and warehouses and, most recently, on its first-ever off-site solar parks.

It announced this week the acquisition of a 49% stake in two US solar parks due to come into operation in coming months. 

Ikea is the world's biggest furniture group and the Ingka Group owns most of its retail operations. 

Brodin told Reuters that Ingka plans to go on investing in wind farms and solar parks. He said it was good business. 

"Being climate smart is not an added cost. It's actually smart business and what the business model of the future will look like. Everything around fossil fuels and daft use of resources will be expensive," he said. 

Brodin urged companies and government leaders at Monday's United Nations-hosted Climate Action Summit in New York to commit to limiting global warming to 1.5 degrees Celsius as called for by scientists. 

More than 400 firms including IKEA, H&M, Coca-Cola and Sony have committed to a UN-backed initiative to help limit global warming to below 2 degrees Celsius. 

Ingka said its renewable energy power now equals more than 1.7 gigawatts (GW) of power - spread over 920,000 solar modules on its sites, 534 wind turbines in 14 countries and the 700,000 solar panels under construction in the US. 

Its two single-biggest investments to date are the 2014 acquisition of a US wind farm for $300m, and that in 2019 of a stake in a wind farm offshore Germany for more than €200m, an Ingka spokeswoman said. 

Ingka, formerly IKEA Group, owns 367 IKEA stores, 23 smaller-format showrooms and 44 shopping centres in 30 markets. 

It said it would roll out its residential solar panel offering in stores to all its markets by 2025, from seven markets currently.