University of Central Florida (UCF) PHY1038 Physics of Energy, Climate Change and Environment Final Practice Exam

To determine how long the world's oil reserves could last at a consumption rate of 18 terawatts (TW), we first need to convert the energy reserves from exajoules (EJ) to terawatts per year for clarity.

1. **Convert the reserves from exajoules to terawatt-hours**:

- 1 EJ is equal to about 277.78 GWh (gigawatt hours).

- Since there are 1,000 GWh in a TW and 8,760 hours in a year, we can conclude:

1 EJ = 277.78 GWh = 0.27778 TW * 8,760 hours = approximately 2.4 TW-hours.

2. **Oil reserves in terawatt-hours**:

- For 10,000 EJ, the conversion yields approximately:

\( 10,000 \, \text{EJ} \times 2.4 \, \text{TW-hours/EJ} \approx 24,000 \, \text{TW-hours} \).

3. **Calculate the total hours of consumption at 18 TW**:

- To find how many hours the reserves could