bar
better
bulb
certificate
chart
compare
comparison
conservation
consumption
cost
ecology
economic
economical
economy
efficiency
efficient
electric
energy
equipment
eu
fluorescent
generation
graph
green
home
illustration
improvement
indicator
lamp
leaf
led
level
light
lightbulb
low
performance
power
rate
rating
red
right
save
saving
solution
technological
usage
utility
watt
white
yellow