The country's third largest building society believes it has a social responsibility to go green and that the sheer size of the fleet industry can influence Britain's vehicle choice.
Speaking at Hit for Six, cost and contracts manager Mary Blackwell told conference delegates moving to environmentally-friendly vehicles can improve a company's image and save fuel costs while drivers can save on tax.
During the 'Power Struggle' session, sponsored by The Energy Saving Trust, Blackwell estimated that the shift towards diesel and LPG vehicles as part of green fleet management policy had saved her company £20,000.
It exceeded targets set by greener fleet certification scheme Motorvate and has reduced business mileage by more than 397,000 miles and reduced fuel consumption by more than 65,800 litres.
It became the only fleet to achieve Motorvate five-star accreditation in July. She said: 'It hasn't been easy by any means but it was a serious long-term commitment we made and we don't now plan to rest on our laurels.'
About 9% of the company's 250-strong user-chooser fleet now drive vehicles powered by LPG. Two years ago that figure was zero.
In 2001, 87% of its fleet was petrol-powered and the remaining 13% diesel. Today, 50% are petrol and 41% diesel. Having senior management and driver buy-in is vital if a green policy is to succeed, delegates heard, as is setting realistic and achievable targets.
Once these targets had been announced Yorkshire Building Society set about communicating the right message to staff and members.
It aimed to reduce CO2 emissions by 12% and mileage by 3%. Persuading and not forcing drivers to adopt such measures was important as was a programme of education and encouragement.
This includes the promise of attractive financial benefits, reduced tax liability and leading by example.