We have a lot of environmental concerns–human health, climate change, endangered species, ecosystem protection, and more.
If all we wanted to know was “Which one releases more carbon dioxide into the atmosphere?”, it would be fairly easy to rank the different energy sources.
If all we wanted to know was “Which one(s) threaten endangered species?”, we might have to compare an impact on a bird species in one area and a fish species in another area.
You can imagine how different people might disagree about which environmental impacts deserve a higher (worse) score.
Imagine two power plant proposals that produce the same energy for the same cost. Write a script for a town hall meeting where people can't agree on which environmental impact.
A good script will: