Rolls-Royce WR-21

The WR-21 is an advanced marine gas turbine designed to power the latest naval surface combatants of the partner nations (e.g the UK's Type 45 AAW Destroyer.) Developed under a US Navy contract, with support from the UK and France the WR-21 was designed and manufactured by an international consortium which includes Rolls-Royce and Northrop Grumman and DCN.

The WR-21 is the first aeroderivative gas turbine to incorporate compressor intercooling and exhaust heat recuperation (ICR) technologies that deliver low specific fuel consumption across the engine's operating range. A reduction in fuel burn of 27% is predicted.
*The intercooler cools air entering the high pressure compressor, reducing the amount of energy required to compress the air.
*The recuperator preheats the combustion air by recovering waste energy from the exhaust, improving cycle efficiency and reducing fuel consumption.

WR-21 development draws heavily on the technology of the successful Rolls-Royce RB211 and Trent families of gas turbines.

It is also a candidate power plant for propulsion of cruise ships and other large commercial vessels, where fuel efficiency and its small size mean improved operational flexibility and significant lifetime cost reductions to operators.