How much energy is being spent as opposed to that being produced?
Solar panels that completely cover a regular size car will only produce about one horse power in full sunlight. A typical car uses WAY more power than the sunlight falling on it could provide, even if the solar cells could convert 100% of it to usable electricity. By the way, power is the rate of using energy. So all you need to know is the rate you are using the energy, not how long you use it. 60MPH will need a certain rate of energy, which will be more than 1 HP in all cases. Then the total energy used depends on how long you are going 60MPH. Twice as long uses twice as much energy, but the power is constant. It is kind of like energy is gallons of water and power is gallons per minute of water flow.
