Indian diesel generator market CAGR real-estate developers Gensets for construction sites K Raheja Corp Raman Sapru Mana Projects PV Shesha Reddy Sudhir Himatsingka Ambuja Neotia construction equipment Devaraja TH M&E Electrical HVAC Sobha Ltd Bureau of Indian Standards Abhishek M Garodia Kirloskar Cummins IoT-driven fuel systems commercial production hydrogen fuel combustion systems