90s
acid
alternative
approve
battery
bulb
care
charge
clean
development
ecological
ecology
economy
electric
electricity
element
emblem
energy
environment
flat
glow
green
icon
industry
innovation
isolated
lamp
light
lightning
like
logo
neon
outline
power
produce
rave
recharge
renewable
resource
retro
set
sign
silhouette
simple
sustainable
thunder
vintage
zigzag