What are the limitations of enegry that can be obtained from the oceans ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Ocean Energy Sources**: The energy obtained from oceans primarily includes tidal energy and wave energy. Both these sources have certain limitations that affect their efficiency and feasibility.

2. **Tidal Energy Limitations**:
- **Dependence on Celestial Bodies**: Tidal energy generation relies on the gravitational pull of the moon and the sun. This means that the energy output is not constant and varies with the relative positions of these celestial bodies.
- **Geographical Constraints**: Tidal energy can only be harnessed in specific coastal areas where the tidal range (the difference between high tide and low tide) is significant. Not all coastal regions are suitable for tidal energy generation.

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