An electric scooter uses 0.02 kWh per mile.

Production of the scooter, including the battery, requires 5 GJ.

The average scooter is used 5 miles per day, every day, for 1 year.

At the end of one year the scooter is recycled and the energy savings for the recycled metal can be considered to return 1 GJ to its life cycle energy inventory.

The primary energy consumption corresponding to the electricity is 9 MJ per kWh. This means that the production of 1 kWh from the electricity system requires input of 9 MJ of energy to the power plants.

The scooters are recharged at night.

Every evening a driver picks up 11 scooters, puts them in a truck, drives them 6 miles home to recharge them over night, and then drives them 6 miles back in the morning to their base location.

The truck energy consumption is 8 miles per gallon. A gallon of gasoline contains 132 MJ.

a. Draw the system diagram, showing the main processes and system boundary