The greenest businesses in Britain will be unveiled next week in the second Sunday Times Green List.

The 2009 Green List reveals the most environmentally aware companies with the most environmentally engaged workforces in Britain. These are the organisations shaping Britain’s approach to curbing climate change, the ones prepared to back up green commitments with concrete improvements to their environmental performance.

The 60 winners from all those who entered The Sunday Times’s quest to find the greenest firms in the country comprise large and small companies with high, medium and low environmental impacts. The results might surprise some people: it is quite possible for a large, high-polluting company to outrank a smaller one with minimal environmental impacts — the key to success in the competition comes from demonstrating real achievement in reducing waste, increasing recycling, cutting energy consumption and generating some energy on-site. Measurable performance and genuine change are what the survey is looking for.

More companies competed this year for a place among our 60 finalists, setting new standards for environmental performance. To succeed here, it is not enough simply to have a swathe of green policies backed by glossy corporate literature.

The Sunday Times Green List is unique in measuring corporate green strategy and performance in parallel with the ability of a company to carry its workforce towards a greener future — “employee engagement”, in the jargon. The views of employees contribute 30% of the marks that determine the final rankings. The other 70% come from surveying performance in areas including environmental management policies, environmental training and internal consultation, energy use and policies for tackling waste. The surveys were devised by The Sunday Times in collaboration with the environmental consultants Bureau Veritas and Munro Global, a market research firm.

Household names competing this year include Tesco, Asda, BT, Coca-Cola Great Britain and Marriott Hotels International. Their final rankings will be revealed at an awards night in London’s Covent Garden on Wednesday, when trophies will be handed out to winners in seven categories plus the ultimate accolade: overall greenest company in Britain. Read all about them in the second Sunday Times Green List next Sunday and online at timesonline.co.uk/bestgreencompanies .

With 29 of last year’s top 50 appearing in this year’s top 60 green businesses, there is already evidence that the survey is becoming a benchmark for environmental excellence. Companies will be able to use it to measure their own performance and that of other businesses.

Eurostar, the cross-Channel train operator, is among those featured in the Green List for a second year. It is currently monitoring electricity consumption on its trains and the effect of different driving styles, aiming to provide drivers with a set of optimum travelling speeds to conserve energy. This will help the company achieve its revised target of cutting carbon-dioxide emissions by 35% by 2012. Having set an original target of a 25% reduction, Eurostar has already achieved a 31% cut since 2007.

Figures from the employee survey show that staff believe Eurostar’s commitment to the environment is serious (earning a green score of 86%) and sense that the company is getting better at doing its bit for the environment (91%). Eurostar’s 1,600 staff say the environment is an everyday consideration for them at work (86%).

Such change — driven from within, rather than imposed from above — is always more likely to produce results.