1978 Cadillac Eldorado, with a turbine engine. This engine was designed to run on powdered coal. Developed after the 1970's fuel crisis scared everyone, concerning the price and availability of gasoline.
The shiny object on the left of the picture, with the flat top, is the powdered coal storage tank. The coal dust was under continuous agitation, to be ready for delivery to the engine. A small conveyor belt moved the dust from storage to the turbine gasifier. The gas pedal actually controlled the speed of the belt.
A small tank of diesel/kerosene was used to start the turbine. After it started, it automatically switched to coal dust.
Thank you for posting this puzzle. I knew nothing about this car until today.
When GM was done with the car, it was shipped to Allison Engineering, which was also involved in the project.