A computers energy source is electricity. When using a computer plugged in or not it is drawing electricity from the battery or from a plug which is connected into the PC and a wall outlet. When there is no electricity the computer cannot function.
Depends what the source of electricity is.
Glucose is the only energy source that the brain can use.
Carbohydrates
light energy
The greates source of energy is the Sun
protiens
Wind
solar
Solar energy
Wind energy.
Carbohydrates
Carbohydrates