Clean energy companies faced a significant sell-off after a new tax bill proposed in the United States triggered deep concerns across the renewable energy sector. Stocks of major US-based renewable energy firms such as Sunrun, the largest rooftop solar company in the country, and NextEra Energy, the leading developer of solar and wind energy projects, recorded sharp declines in a single trading session. Losses ranged between 7% and an alarming 37%, shaking investor confidence and dragging dow