Energy density is the amount of energy stored per kilogram of the energy source. The table below compares an electric delivery van with a petrol delivery van:
| Power source | Energy density (MJ/kg) | Mass of power source (kg) | Total mass of van (kg) |
|---|---|---|---|
| Battery (Electric) | 1.2 | 350 | 2200 |
| Petrol (Petrol Van) | 43 | 45 | 1800 |
Show why the petrol van has a greater range than the electric van. Use data from the table. Assume the efficiency of the two vans is the same. Include calculations in your answer.