Now that China has overtaken the U.S. to be the largest issuer of green bonds, some investors are showing skepticism over a regulatory regime that even allows sales by coal projects. Chinese electric car and wind-power companies joined banks to raise the equivalent of $8.8bn selling green notes this year, a third of global issuance, Bloomberg data show. With 95.4% of those offerings denominated in yuan and local standards differing from global ones, there are obstacles for foreign funds. Clean-coal power stations qualify for the status in China, even though they can conflict with some investors’ mandates. China approved more than RMB 100bn($15.2bn) of sales of green bonds in the first five months of this year.