Introduction

More energy required because of growth in population and 1.

What’s needed:

• renewable energy sources
• methods that won’t create pollution

Wave energy

Advantage: waves provide a 2. source of renewable energy

Electricity can be generated using offshore or onshore systems

Onshore systems may use a reservoir

Problems:

• waves can move in any 3.
• movement of sand, etc. on the 4. of the ocean may be affected

Tidal energy

Tides are more 5. than waves

Planned tidal lagoon in Wales:

• will be created in a 6. at Swansea
• breakwater (dam) containing 16 turbines
• rising tide forces water through turbines, generating electricity
• stored water is released through 7. , driving the turbines in the reverse direction

Advantages:

• not dependent on weather
• no 8. is required to make it work
• likely to create a number of 9.

Problem:

• may harm fish and birds, e.g. by affecting 10. and building up silt

Ocean thermal energy conversion

Uses a difference in temperature between the surface and lower levels

Water brought to the surface in a pipe