accumulator
adapter
battery
bulb
cable
charge
collection
concern
connect
conservation
eco
ecologic
ecology
economic
economical
economy
efficiency
efficient
electric
electrical
electricity
energy
equipment
fluorescent
glowing
icon
illumination
lamp
light
lightbulb
lighting
line
neon
pictogram
plug
power
rechargeable
reduce
save
saving
set
shine
shining
sign
socket
spiral
switching
symbol
technology