Weekly investors roundup: GIC leads $135 million fundraiser for energy storage company Powin; Canadian fund Aimco to set up Singapore office for regional expansion

Singapore's GIC leads a $135 million fundraising round for US-based energy solutions firm Powin; Alberta Investment Management Corp is setting up its first Asian office in Singapore with an eye on Asian private equity; Ontario Teachers’ Pension Plan Board will acquire a 70% stake in New Zealand's TowerCo; and more.