Exhaustdriven

Exhaustdriven is a term used in engineering to describe systems and devices that derive mechanical work, electrical power, or actuation from the exhaust gas stream of an internal combustion engine. The concept covers energy recovery, pressure extraction, and exhaust-gas–powered components that make use of exhaust momentum, pressure, or temperature to perform work or improve overall efficiency.

The most common implementations are based on exhaust-driven turbomachinery. An exhaust turbine can be used to extract energy from the exhaust flow, either to drive a compressor in a turbocharger or to power an additional turbine linked to a crankshaft in turbocompounding arrangements. In these setups, energy that would otherwise be lost as heat is converted into useful work, improving engine efficiency and sometimes reducing fuel consumption or emissions. Exhaust-driven generators or hydraulic pumps provide similar functions by converting exhaust energy into electrical or hydraulic power for auxiliary systems.

Other approaches fall under exhaust energy recovery, such as using exhaust heat in a secondary cycle or attaching small turbines to capture energy for ancillary loads. These methods are most common in heavy-duty vehicles, marine applications, and stationary power plants where waste heat from exhaust constitutes a significant energy source.

Advantages of exhaustdriven systems include potential efficiency gains, quieter operation, and reduced fuel use in some configurations. Limitations involve added system complexity, potential back-pressure effects on engine performance, thermal management needs, and higher upfront costs.

See also turbocompounding, turbocharger, exhaust gas recirculation, waste heat recovery.