AIB will begin examining the link between the carbon impact of business borrowers, and their loan performance.
A new, sustainable business unit led by Ray O'Neill has been tasked with integrating environmental sustainability into the bank's lending approach.
The initiative is only in its infancy. Speaking at a climate-change event in Dublin yesterday, Mr O'Neill outlined the concept of a "triple bottom line", where the social and environmental impact of lending will be considered alongside financial return.
Also speaking at the event - hosted by the French Embassy, KPMG and the ISI Centre - was Virginie Pelletier of BNP Paribas. The lender keeps a private list of about 100 companies it will not lend to based on environmental and ethical concerns, she said.
France's Ambassador to Ireland, Jean-Pierre Thébault, called on Irish businesses to prioritise energy efficiency and said climate change should become an important element of Ireland and France's bilateral co-operation. This year's Paris Climate Conference aims to secure the first binding universal agreement on climate change in 20 years of UN negotiations.