How do fossil fuels generate electricity in a typical power plant?

• A. They are burned to produce heat, which boils water to create steam that drives turbines connected to generators
• B. They directly convert chemical energy to electrical energy without moving parts
• C. Solar energy is converted to electricity via photovoltaic cells in the same plant
• D. Electrons are harvested from fossil fuels through piezoelectric generators

Answer: (A)

Fossil fuels generate electricity by releasing heat through combustion, which then drives a mechanical process to produce power. The heat boils water in a boiler to create high-pressure steam. This steam expands and pushes the blades of a turbine, making it spin. The turbine is connected to a generator; as the turbine turns, a magnetic field inside the generator changes relative to coils of wire, inducing an electric current that is sent out as electricity. The steam is cooled and condensed back into water to be reused, completing the cycle. This sequence—chemical energy in fuel becoming heat, then mechanical energy in a turbine, then electrical energy in a generator—describes the typical thermal power plant operation.

Why the other ideas don’t fit: there isn’t a large-scale fossil-fuel plant that converts chemical energy directly into electricity without any moving parts; mechanical rotation is essential to drive the generator. Solar cells involve a different technology entirely, converting sunlight directly to electricity, not burning fuel to produce steam. Piezoelectric generators rely on tiny deformations to generate charge and aren’t used to scale up from fossil fuel combustion to electricity.