High efficiency solid state engine


Date Thursday January 29th 2009
Time 4:00-5:00pm
Venue George E. Pake Auditorium, PARC

PARC Forum

Until now, thermodynamic engines that use compressible working fluids have generally been mechanical devices. These devices have inherent difficulties in achieving high compression ratios and in achieving the near constant temperature compression and expansion processes needed to approximate Carnot equivalent cycles. Solid-state thermoelectric converters that utilize semiconductor materials have only been able to achieve single digit conversion efficiency.

In this talk, Dr. Johnson will discuss the Johnson Thermoelectric Converter System (JTEC), an all solid-state engine that operates on the Ericsson cycle. Equivalent to Carnot, the Ericsson cycle offers the maximum theoretical efficiency available from an engine operating between two temperatures. The engine has no moving parts, and it does not require oxygen or a continuous fuel supply – only heat.

The JTEC engine is scalable and has applications ranging from supplying power for Micro Electro Mechanical Systems (MEMS) to power for large-scale applications such as fixed power plants. The technology is applicable to field generators, land vehicles, air vehicles and spacecraft. The JTEC engine could utilize heat from fuel combustion, solar, low grade industrial waste heat or waste heat from other power generation systems including fuel cells, internal combustion engines and combustion turbines. As a heat pump, the JTEC engine could be used as a drop in-replacement for existing HVAC equipment in residential, commercial, or industrial settings.


Dr. Lonnie Johnson is President and Founder of Johnson Research & Development Co., Inc., a technology development company, and its spin-off companies, Excellatron Solid State, LLC, and Johnson Electro Mechanical Systems, LLC.

Johnson holds a B.S. degree in Mechanical Engineering, an M.S. degree in Nuclear Engineering, and an honorary Ph.D. in Science from Tuskegee University. Upon graduation, he joined the Air Force and served as an Advanced Space Systems Requirements Officer at Strategic Air Command headquarters. He was twice awarded the Air Force Achievement Medal and the Air Force Commendation Medal. After leaving the military, he joined the Jet Propulsion Laboratory (JPL) in California. During his nine year career with JPL, he received multiple achievement awards from NASA for his work in spacecraft system design for the Galileo Mission to Jupiter and the Mars Observer projects, and was instrumental in the Cassini Mission to Saturn.

In 1989, he formed his own engineering firm and licensed his most famous invention, the SuperSoaker® water gun, to Larami Corporation. Two years later, the SuperSoaker, which has generated over $1 billion in retail sales, became the number one selling toy in America. Currently, Lonnie Johnson holds over 100 patents, with over 20 more pending, and is the author of several publications on spacecraft power systems.

Johnson's companies, Excellatron Solid State and Johnson Electro Mechanical Systems (JEMS), are developing revolutionary energy technology.

Excellatron (http://www.excellatron.com) is introducing a new generation of rechargeable battery technology that will solve many of the problems related to technology mobility in the future. This technology has the potential to revolutionize the battery industry, providing a source of energy many times that which exists today in a substantially reduced size.

JEMS (http://www.johnsonems.com) has developed a thermodynamic energy conversion technology that converts thermal energy to electrical energy with significant advantages over alternative systems, and the potential to revolutionize the global energy market when fully commercialized.

Articles on Lonnie Johnson have appeared in numerous publications including Popular Mechanics, Time Magazine, the New York Times, and Inventor's Digest. In October 2008, he received a "2008 Breakthrough Award" from Popular Mechanics for his invention of the JTEC. He has been featured on the National Geographic channel's "Science Times TV," CNBC's "Business Nation," and as a guest expert on USA Network's "Made in the USA."

Johnson serves as Chairman of the Board of Directors of the Georgia Alliance for Children, an organization which serves as an informed and influential voice to protect the rights and interests of Georgia's needy and powerless children. He is a member of the 100 Black Men of Atlanta, and a Board member of the Hank Aaron ‘Chasing the Dream' Foundation.

Additional information

Focus Areas

Our work is centered around a series of Focus Areas that we believe are the future of science and technology.

Licensing & Commercialization Opportunities

We’re continually developing new technologies, many of which are available for Commercialization.


PARC scientists and staffers are active members and contributors to the science and technology communities.