Study Figure 1.
Figure 1: Energy mix of Country Z (percentage of total electricity generation), 2005–2025
| Year | Coal | Gas | Nuclear | Renewables (Wind/Solar) | Oil |
|---|---|---|---|---|---|
| 2005 | 40% | 30% | 15% | 5% | 10% |
| 2010 | 30% | 35% | 16% | 10% | 9% |
| 2015 | 20% | 40% | 15% | 18% | 7% |
| 2020 | 5% | 38% | 14% | 38% | 5% |
| 2025 | 1% | 32% | 12% | 51% | 4% |
Suggest one possible reason for a change in the energy mix shown in Figure 1.
