Andrei - I really like what you've made. To me it's simple yet still colorful. The road (that just shows up in the drop, and doesn't blur or pull on it) to me looks clean and clarifies the transportation connection. And I think we are leaning toward liking a one-color acronym.
I have a board of 8 that will help make the final decisions; I'll have to see what we decide as a group. One other idea you may consider is this: we serve Clean Cities coalitions, and our collective DOE logo can be found here:
http://www1.eere.energy.gov/cleancities/toolbox/logos.html. It's the sun rising over the city skyline. Is there a variation of this that doesn't complicate the design too much... or another creation you could make that doesn't copy this but perhaps includes most of the elements we are looking for but gives a nod to that logo?
We appreciate all your hard work!
Thanks,
Jonathan