Two communications firms, two construction companies and the largest power generator in Britain to produce only renewable energy landed the top five slots in the Sunday Times' second annual list of "Best Green Companies" in the United Kingdom.

Forster, a communications company specializing in ethical marketing and social PR, led the roster of 60 firms that the Sunday Times compiled from a field of 98 entries. Last year's list included only 50 companies.

Second place went to the National Magazine Company, the Hearst subsidiary that produces the U.K. editions of many popular international periodicals including Cosmopolitan, Good Housekeeping, Harper's Bazaar, Esquire, Country Living, among others.

Construction firms Willmott Dixon Group and Skanska U.K., took third and fourth place, respectively.

Infinis, the largest power company in the U.K. to generate only renewable energy secured the fifth slot.

The supermarket firm Tesco, with 185,000 employees, was the largest company to make the list and ranked No. 15. Office supply company Wiles Greenworld, with 50 employees, was the smallest business on the list; it ranked No. 52.

Small and midsized companies dominated the top 10 percent of the list. Big companies didn't make a showing until the No. 7 spot.

The first five large firms on the list were telecommunications company BT Group at No. 7; the government's Environment Agency at No. 8; Carillion Construction, No. 11; Tesco, No. 15; and information technology firm Logica U.K., No. 16.

The complete list is available from the Sunday Times online.