** Solar firm Sunnova Energy's NOVA.N shares drop 12.9% to $0.32 premarket
** Company preparing restructuring talks with creditors that could include filing for bankruptcy, Wall Street Journal reports late Wednesday, citing sources
** Company holds roughly $8.5 billion in debt, according to the report
** NOVA warned March 3 it had doubts about its ability to continue as a going concern, as current cash flow and existing financing agreements not enough to fund operations
** Going concern warning sent NOVA shares to an all-time low on March 3
** Company on Monday named Paul Mathews as president and CEO
** As of Wednesday's close, stock down more than 89% YTD
(Reporting by Lisa Pauline Mattackal)
((LisaPauline.Mattackal@thomsonreuters.com))