Alternative enerwhat-in-a-what-what?
Alternative (or renewable, it depends who's language you're speaking) energies make sense. Plain and simple. We are destroying our natural surroundings because of a delusional comfort with flicking a switch without asking some tough questions: where is this energy coming from? how is it being generated? Were any countries invaded under false pretenses for me to be able to keep all the rooms of my house lit, day and night?
The last thing I want to do is make it look like people who are conscious about these issues hold some sort of moral superiority over those who still litter. I think the best way to appeal to the latter is to show the personal benefits of making a change to environmentally friendly technologies. An easy example is switching to energy-efficient light bulbs, a decision that can save you, on average, 30$ or more over each light bulb's lifetime.
Read a book. Educate yourself on issues that affect you either directly or indirectly. An iceberg melting in Antarctica may not seem like such a big deal until your house turns into an aquarium.
I've added some links to the sidebar that should get you started on the right track. Feel free to start a discussion in the comments or just say hello.