George Osborne, the shadow chancellor, applauded "the leading role" Britain's most environmentally aware companies have taken to address climate change in a keynote address at The Sunday Times' second annual Best Green Companies awards ceremony in central London last week.

"The argument that if you are pro-business you must be anti-green was very real three or four years ago. But today it is no longer valid," he said. "And the people in this room prove it." Addressing the assembled companies, he pledged to help "set the framework so that you can continue to lead Britain's approach to addressing climate change".

Sixty companies made this year's Green List, up from 50 last year, despite a marked increase in entrants and a higher standard. The winners, profiled in a special Sunday Times supplement, range from corporate giants with thousands of employees to small family-owned firms with just a handful of workers. Those who won a place include Tesco, Coca-Cola, Skanska, Eurostar, British Telecom and Marriott Hotels.

What they all demonstrate are measurable changes in categories like energy consumption, waste, and recycling. Uniquely, the extent to which companies involve their workforces in the drive to pollute less and increase efficiency was also investigated. The result was an exhaustive survey, carried out by the Sunday Times' partners: Bureau Veritas, the environmental certification group, and Munro Global, data analysts. The two firms questioned nearly 21,000 employees.

Presenting the awards, Richard Caseby, Sunday Times managing editor, said the venture reflected the changing mood in the business world toward environmental issues. "Today it is not enough to make a profit for shareholders," he said. "Companies have a wider responsibility to ensure that they minimise the environmental impact of what they do.

"There may be plenty of environmental awards but this is the first that has a robust methodology to measure environmental performance and also a survey of staff to find out whether the green sheen is more than skin deep."

Tesco won the award for being the best large company for corporate environmental strategy. The top ranking for the supermarket giant, which employs more than 185,000 people, scored highly on the employer survey, which measures improvements in gas, power and water use, waste reduction and training for staff.