alternative
blades
burning
clean
colorful
conservation
country
countryside
development
ecological
ecology
electric
electrical
electricity
energy
environment
environmental
environmentally
farm
force
generate
generator
german
germany
global
green
industrial
industry
landscape
mill
natural
nature
plant
power
powerplant
propeller
renewable
resource
rotate
rotation
silhouette
sky
sunrise
sunset
sustainable
technology
turbine
wind
windmill
windturbine