According to the Western Mail, three-quarters of the firms surveyed also introduced energy saving schemes to counter the rises.
Discussing the findings with the newspaper, Mr Antoniazzi said that only a third of firms have achieved reductions through the initiatives.
"Looking ahead, businesses need to address this issue and start making serious changes in the working environment to ensure that the changes really do offer a reduction in fuel usage," he added.
It was also found that those working at larger firms are put off from becoming greener by red tape.
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