SunEdison (NASDAQOTH: SUNEQ) is already bankrupt, but the problems at its yieldcos TerraForm Power (NASDAQ: TERP) and TerraForm Global (NASDAQ: GLBL) are just beginning. This week, it was revealed that holders of $1.25 billion in bonds sold by TerraForm Power and $760 million in bonds from TerraForm Global have filed notice of default.