Well, no one really "invented" electricity, but you can ask 
who discovered it. While people have known about the 
powerful effects of lightning for thousands of years, the 
first person to discover that lightning was a naturally 
occuring form of electricity was Benjamin Franklin. In 
1752, during a dangerous electrical storm, Franklin flew a 
kite that had a metal key at the bottom of the string. When 
a bolt of lightning hit the kite, a spark of electricity 
flew from the key! From this experiment, Franklin invented 
the lightning rod, which attracts lightning and draws it 
into the ground. This saves many buildings from burning 
down.