What type of system captures heat from exhaust for additional electrical generation?

A combined-cycle system effectively captures heat from exhaust gases to generate additional electricity. This system works by utilizing both a gas turbine and a steam turbine. Initially, the gas turbine burns natural gas, producing high-temperature exhaust gases. Instead of allowing this hot exhaust to be wasted, the combined-cycle system directs it to a heat recovery steam generator (HRSG).

The HRSG harnesses the heat from the exhaust gases to produce steam, which then drives a steam turbine. By using both types of turbines in tandem, the system not only improves overall efficiency but also enhances electrical output. The ability to convert what would have been lost energy into usable power exemplifies the design and operational advantages of a combined-cycle system in modern energy generation.

The other options do not pertain to systems that effectively utilize exhaust heat for additional generation. Therefore, they do not align with the fundamental principles of energy recovery in power generation scenarios.