University College Cork (UCC) has cut its energy usage by almost a quarter in recent years and is ranked the world's number two "green" university.
It is the second year in a row that UCC has taken the runner-up spot in a global league table that compares the efforts of universities towards campus sustainability and environmentally-friendly university management.
The latest Universitas Indonesia (UI) Greenmetric World University Ranking compared 360 universities in 62 countries and UCC also took second position for the "urban" campus category.
UCC's energy efficiency record puts it well on the road to meeting the national target of a 33pc reduction by 2020.
The "green" initiatives adopted by UCC span behavioural as well as technical improvements and include retrofitted buildings, solar panels, a wind turbine, efficiency improvements to lighting boilers, heat recovery, ventilation and an ongoing 'turn off your printer before you go home' awareness campaign.
The college has also saved over 750,000 cubic metres of water since 2007, through measures such as rapid leak detection, waterless urinals and re-use of groundwater, for instance, for toilets in certain areas.
UCC came second after the UK's University of Nottingham. Other universities making the overall top 10 include University of California, Davis (4); University of Oxford (5); University of Connecticut (7); and University of California, Berkeley (9).
The University of Limerick is the next placed Irish university in the UI rankings, at 11th, while Dublin City University is 53rd, Trinity College Dublin, 104th and Dublin Institute of Technology, 193rd.
UCC's "green" credentials have been widely recognised both at home and abroad, including a recent shortlisting as the only Irish representative among 17 finalists for the European Business Awards for the Environment (EBAE).
The university's Director of Buildings and Estates, Mark Poland, said student buy-in from the outset had been pivotal to the success of UCC's "green" campus.