Sometimes being environmentally friendly means using new technologies like solar and wind power, but sometimes it is simply about doing what we have always done, but doing it in a smarter way.
URISA, an association of GIS professionals, has an annual competition for students in the GIS field to produce papers and posters on using GIS to solve real world problems. One group in Maine has used GIS technology to model how to reduce the cost of transportation of recyclables from collection locations to the processing plants. They will still be using the same technology to collect the recyclables, but they will be reducing the distance that they are transported, resulting in an enormous savings in CO2 generation and a reasonable savings in cost. This will be especially valuable if we ever move to a “mining” paradigm for dealing with recyclable waste.
To read more about how they propose to do this I recommend that you read Minimizing Transportation Costs with Location-Allocation Analysis: An Application to Recycling « GIS and Science.
This is yet another example where students have come up with innovative solutions to problems that we have lived with for ages. Maybe there is hope for us yet!