Hmm. Does it have to be a major in the engineering school? Have you considered majoring in some sort of science? Do you plan on going to grad school or do you plan on going to work immediately after you graduate?
I notice you didn't mention windmills - are you afraid of heights? They are the one alternative energy source that, right now, is economically viable. Mechanical engineering would best suit the windmill business, although some electrical engineering is involved. ME and EE would be the best engineering generalist majors.
If you do not enjoy the chemistry class you are taking now, you are likely to hate the overall ChemE curriculum.
The reality of engineering is that, until you get to the program management level, you would likely work on one small part of the larger issues within your interests: the charging circuit for that plug in hybrid or the injection molded parts for the fuel cell. Does your school have career counseling services? They might be your best resource right now.
Any branch of engineering will have to do with all these things. Engineering becomes very specific as you move on and you can decide on that as you take classes. Just take classes in your college of engineering and see what you enjoy the most.