The winning commercial aired this summer and was part of an integrated campaign aimed at highlighting the company's ethical credentials. It featured members of the public voicing opinions on subjects ranging from climate change to human rights, and how easy it is do something positive.
Zoe Shore, account director at Dig For Fire, said: "The Green Awards prove that ethics and doing the right thing doesn't have to be dull and worthy.
"In fact, creativity and promoting green issues across different media platforms is the key to encouraging greater consumer participation and behavioural change."
The Co-operative Bank has also supported Friends of The Earth's Big Ask national press campaign to table a climate change bill that will aim to set annual government emission targets.
The Green Awards, which are sponsored by Media Guardian and Energy Saving Trust in partnership with Friends of the Earth, were devised to give recognition to brands that highlight sustainable development and corporate social responsibility in ad campaigns.
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