John Carrington, the former CEO of MiaSolé and architect of its sale to Hanergy, has been hired as CEO of Stem. He replaces the relatively recently hired CEO Salim Khan, who will now be spending more time with his family. Prior to MiaSolé, Carrington served as EVP of Marketing and Business Development at First Solar. Stem just closed a $15 million Round B from GE Ventures, Iberdrola, and Angeleno Group. The startup employs energystorageand software to provide "energy optimization services." 

Imergy Power Systems, formerly Deeya Energy, added Bill Watkins as CEO. Watkins is the former CEO of VC-funded LED firm Bridgelux. Until recently, Deeya built flow batteries for off-grid telecom applications. The firm has shifted its flow-battery chemistry and now targets the utility-scale energy storage market. 

QuantumScape, a stealthy energy storage company funded by Khosla Ventures, has been rumored to have Bruce Sohn, formerly of First Solar, as its CEO. That continues to be the rumor.

David King has officially resigned from troubled solar vendor Suntech's board of directors. He stepped down from his role as CEO and interim CFO in September.

Vivint Solar named Dana Russell as CFO and Rich Larson as VP of finance. Prior to joining Vivint Solar, Russell was the CFO of software company Allegiance, as well as SVP and CFO of Novell from 2005 to 2011. Larson was most recently director of corporate planning and financial reporting at software firm The Attachmate Group.  

Atiye Bayman was promoted to Chief Technology Officer at MiaSolé in September.

Microinverter maker i-Energy named Bernd Kohlstruck as VP of Global Sales. Prior to joining i-Energy, Kohlstruck was VP and Managing Director at microinverter maker Enecsys Europe. Prior to that, he was a VP at Xantrex. 

Michael Mendik was named as GM of U.S. technology for SMA America Production, the manufacturing division of SMA. Before joining SMA, he was with ABB, working his way up to GM of the company's surge arrester business.

Opower added Palo Alto Networks CEO Mark McLaughlin to its Board of Directors. Energy efficiency player Opower has been beefing up its board in advance of an expected IPO.