Environmentalist-fundamentalist. An envirofundie (or envirofundy) is a campaigner for the environment who does not believe in logic and reason as presented by the scientific community.
The average envirofundie is well meaning, but misguided. Typical believers are unemployed humanities students, generally with long unwashed hair wearing dirty high visibility jackets and will travel by bicycle. They will quote unpublished, non-reviewed 'scientific' facts to support their argument. They ignore genuine scientific peer-reviewed journals.
An envirofundie will typically reject any engineering proposals for energy production out of hand, even if these are 'green' technologies such as wind or tidal. Nuclear energy causes envirofundies to lose control of themselves and any semblance of logic and reason.
An envirofundie uses statistics like a drunk uses a lamppost, for support, not illumination. Many are members of Greenpeace and Friends of the Earth.
Hey, did you hear that treehugger on the TV last night? He was one idiot envirofundie!