Even if a single person can't change the world, being a tiny part of a solution is better than being a tiny part of a problem.   

Quoting -RG-,

reply 3

I also changed (expensive) all our light bulbs to LEDs....People do not change overnight and the cost of change is well, pretty spendy.  

There's one of the main issues right there. People ultimately think of themselves first. So the way to make them concerned about the environment/climate is this: Tell them how much money they can save by going the environmental way. Yes, that means government subsidies, buybacks etc etc but if you get more money to keep in your pocket which means more money to pay off that pesky mortgage more quickly, are you really going to care? The flip side is to make the non-environmental way hellishly expensive...