background
blue
cable
city
cloud
color
communication
connection
current
danger
electric
electrical
electricity
energy
engineering
environment
equipment
high
ice
icicles
industrial
industry
line
lines
metal
network
old
phone
pole
poll
power
road
sky
steel
structure
sunlight
supply
tall
technology
telephone
tower
transmission
transmit
volt
voltage
white
wire
wires
wood