The De Vere hotel group saved enough energy last year to power the Olympic Stadium non-stop for more than six months, according to figures released by the CRC Energy Efficiency Scheme.
On average, the group saw a 6% energy reduction last year that would have been enough to keep the iconic London venue floodlit from the opening ceremony through to May 2013.
De Vere Hotels reduced its energy consumption by 9%, whilst De Vere Village Urban Resorts and De Vere Venues reduced theirs by 4% each.
If the carbon emissions were water, the past year's savings across the business would fill 776 Olympic-sized swimming pools, the company said.
Andrew O'Brien, group property director at De Vere, said: "This is fantastic news for us, and a positive step forward to meeting our CSR corporate social responsibility] goals.
"Saving energy and reducing our carbon emissions is a priority for us, and our achievements reflect our focus on this key area."
The mandatory report on carbon emissions is part of a scheme aiming to improve energy efficiency in large public and private sector organisations, which are responsible for about 10% of the UK's emissions.
By Janie Manzoori-Stamford
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