Organizers of the Alternative Clean Transportation (ACT) Expo, today announced the featured speaker lineup for its 2015 conference and exhibition taking place May 4 to 7 at the Kay Bailey Hutchison Convention Center in Dallas, Texas. Throughout the four-day event, attendees will gain insight into the promising future of alternative fuels and clean vehicle technologies–including electric, hybrid, hydrogen, natural gas, propane autogas, clean diesel, renewables, and efficiency technologies.