Clean200 list shows continued strong performance of world's largest green companies against stock market benchmarks
Stock value of Clean200 list, which ranks firms according to their clean energy revenues, falls behind fossil fuel benchmark due to solar tariffs and a surge in oil prices
Clean 200 companies generated total return of 32 per cent over the last 18 months, compared to 15.7 per cent for fossil fuel benchmark index
China playing leading role in corporate clean energy landscape with almost the double number of US companies in latest rankings