What is an example of a cogeneration system?

A cogeneration system, also known as combined heat and power (CHP), is designed to efficiently produce both electricity and useful thermal energy from the same energy source. The correct answer highlights the process where exhaust gases from a turbine-driven generator are utilized to produce steam. This is a prime example of cogeneration because the system captures waste heat that would otherwise be lost and uses it to generate steam, which can then be used for heating or industrial processes.

In this context, the efficiency of energy use is maximized as it captures and recycles energy that would typically be wasted, providing both electrical power and thermal energy simultaneously.

The other options, while they refer to types of energy systems, do not encapsulate the dual-output nature characteristic of cogeneration. For instance, using a gas-fired boiler for space heating focuses solely on thermal energy without an associated electricity generation component. Likewise, exhaust gases driving a turbine for electricity strictly addresses the generation of electrical power without thermal recovery, and combining solar energy with natural gas does not inherently indicate a system designed to capture and utilize waste heat for additional energy production. Thus, option C stands out as the best example of a cogeneration system.