automobile
blue
boil
boiler
cable
capacity
chemical
chemistry
circuit
electrics
energy
energy saving
engineering
environment
factory
fuel
gas
gasoline
heavy
high
industrial
industry
landscape
light
manufacturing
metal
night
oil
petroleum
pipe
pipeline
plant
pollute
pollution
power
power plant
product
production
refinement
refinery
saving
sky
smoke
sphere
steam
storage
tank
technology
tower
worker