The stadium, whose attendance numbers will hit close to two million before the end of the year and over 120,000 this weekend, has hired facilities management company Dalkia to calculate its carbon footprint.

Croke Park stadium director Peter McKenna says he ordered the audit partly as a cost-cutting measure but also to appeal to a younger generation of customers who expect businesses to be operate in a more environmentally responsible manner.

"In the last 18 months, the cost of utilities has taken a massive leap. Also, measures to run a business more environmentally are likely to be legislatively imposed on us in the future. That's one of the motivations, " he said.

"Aside from that, however, there are a group of young people in Ireland now who are demanding this. Every generation brings something different to the business community and young people don't want their day out in Croke Park to cause excessive damage to the environment.

"They want these problems tackled in a responsible way, " he added.

Management is looking at ways to segregate more of the rubbish generated at the stadium so that as little as possible ends up in landfill sites.

They are also considering reducing the capacity of fridges in the corporate boxes . . . a measure that may upset their lucrative executive customers.

"We may be putting in smaller fridge units because essentially they are not used all that much, only for snacks, " said McKenna.

Croke Park is powered by eight generators but only one or two are used at a time, with the rest kept redundant as back-up for floodlights, broadcast units and in case of a power cut.

Just turning on the floodlights for an evening throw-in costs the stadium 1,400.