If Anil Ambani's Reliance Power is making waves get ready for another power packed public offer, India's largest hydel power company NHPC is now planning to tap the markets too. NHPC likely to offload 15 per cent stake. The company also plans to divest 10 per cent new shares and 5 per cent of the existing government stake. NHPC has a mandate to sell up to 24 per cent stake and to raise about Rs 1,700 crore by issuing 167 crore shares.