air
atmosphere
blue
chimney
climate
cloud
coal
contamination
damage
dirty
ecological
ecology
emissions
energy
environment
environmental
factory
fuel
fumes
gas
global
industrial
industry
manufacturing
nature
orange
pipe
plant
pollution
power
production
sky
smog
smoke
smokestack
stack
station
steam
sun
sunset
technology
tower
toxic
vapor
warm
warming
white
yellow