Reuters Market Eye - NHPC shares jump 6 percent. Traders say the focus could shift to hydro power as an alternative to coal in electricity generation.
NHPC is the top gainer in BSE large-cap stocks called "A group" and NSE equity derivatives.
Volumes at 1.4 times of the five-day average.
The Supreme Court on Monday declared coal block allocations made since 1993 illegal.
(Reporting by Abhishek Vishnoi)