Power Generation

• Thermal (coal, gas) — fuel heats water to steam that spins a turbine–alternator (Rankine cycle); combined-cycle gas plants reach about 60 % efficiency.
• Hydro — $P = \eta \rho g Q H$ (flow $Q$, head $H$); fast to start, used for peak demand; pumped storage acts as a giant battery.
• Nuclear — fission heats steam; steady base-load.
• Solar PV — semiconductor cells produce DC, converted by inverters.
• Wind — $P = \tfrac{1}{2}\rho A v^3 C_p$, with the Betz limit $C_p \le 0.593$.

Renewables now make up a fast-growing share of India's installed capacity; their variability requires storage, forecasting and flexible grids.