Stationary natural gas engines have the potential to reach very high efficiencies but are currently limited by spark plug reliability and lifetime performance. In particular, spark plugs require significantly more power under high pressure conditions and have difficultly igniting lean fuel-air mixtures. Furthermore, ignition under high pressure conditions leads to electrode erosion which significantly reduces the lifetime of the spark plug. Laser ignition provides a solution to all of these problems but its power output remains limited at high temperatures. If high temperature lasers are developed and used in stationary natural gas engines, much higher efficiencies could be realized, leading to significant fuel savings and emissions reductions.
Project Innovation + Advantages:
Princeton Optronics will develop a low-cost, high-temperature capable laser ignition system which can be mounted directly on the engine heads of stationary natural gas engines, just like regular spark plugs are today. This will be done using a newly developed high-temperature Vertical Cavity Surface Emitting Laser (VCSEL) pump combined with a solid-state laser gain material that can operate at temperatures typically experienced on a stationary natural gas engine. The key innovations of this project will allow the laser pump and complete laser ignition system to deliver the required pulse energy output at the engine block temperature and create a solution that is entirely exchangeable with a conventional spark plug. This avoids the need for an expensive and complicated fiber optics system to deliver the laser energy to the engine’s combustion chamber from an off-board, cooled location. If successful, the high temperature laser ignition system will provide a reliable solution to extend the lean limit of combustion and increase the efficiency of stationary natural gas engines, resulting in significant fuel savings and emissions reductions.