alternate
alternative
alternator
auxiliary
backup
battery
building
current
device
diesel
electric
electrical
electricity
emergency
energy
engine
equipment
external
fuel
gas
gasoline
generation
generator
high
house
industrial
industry
input
internet
interruption
metal
mobile
power
powerful
problems
protected
server
service
source
standby
supply
support
surges
technology
uninterrupted
unit
ups
utility
volt
voltage