KUALA LUMPUR: Tenaga Nasional Bhd’s (TNB) wholly-owned subsidiary, TNB International Sdn Bhd (TNBI) has acquired the controlling equity stake in Vortex Solar Investments S.a.r.l. (Vortex Solar) from Beaufort Investments S.a.r.l, a subsidiary of EFG Hermes Holding SAE. The proposed deal is worth £11 million (RM59.