The document discusses several concepts for more efficient and environmentally friendly fuel delivery trucks of the future. These include a lightweight, solar/LP gas hybrid tanker from AirFlow Truck Company that is over 1000 pounds lighter and 50% cheaper to operate than conventional models. Another concept is a diesel-electric hybrid tanker from Scania designed to be eco-friendly and economical. A third concept is the DocomUSA HST tanker designed to be more aerodynamic and allow for a steerable trailer to increase maneuverability while carrying more payload.