Teledyne Energy Systems, Inc. (TESI), a Teledyne Technologies Company, is a leading global provider of on-site gas and power generation systems and fuel cell test equipment. TESI continuously strives to exceed our custome......Teledyne Energy Systems, Inc. (TESI), a Teledyne Technologies Company, is a leading global provider of on-site gas and power generation systems and fuel cell test equipment. TESI continuously strives to exceed our customers expectations by listening to their requirements and offering the industry best solutions, based on a 50+ year history of material and production excellence. TESIs product offerings are listed below. For additional information, or questions specific to your application, please contact TESI by e-mailing energy.systems@teledynees.com or calling 410.771.8600.