Billionaire Gautam Adani-led Adani Group is gearing up for a $100 billion investment in capital expenditure over the next five years. Speaking at the 5th Annual Conference of the Society for Minimally Invasive Spine Surgery- Asia Pacific (SMISS-AP) on Friday, he said the investment earmarked by the power-to-port conglomerate will be unprecedented in India’s private sector history, the Economic Times reported.