Energy in the Ocean
Through wave energy, the waves create up and down motion or side to side motions that power generators underneath the water. Wave energy is not considered to be a reliable energy source because anything using wave energy would only be available for use when near the ocean, therefore this would be best near the ocean.
Tidal Energy
Tidal energy is a type of hydro-power that converts the energy of tides into electricity. Tidal streams are predictable thus enabling accurate forecasts of future power take off. The drawbacks are they are a possible surface hazard.
OTEC
OTEC is Ocean Thermal Energy Conversions. This uses seawater to turn solar energy into electricity off. The benefits of OTEC plants are that it contributes to future energy mix offering a sustainable electricity production method. It is also cold and filled with nutrients. The drawbacks of OTEC are that it requires a lot of money and can only be done where the thermal gradient is because within the upper 1000 meters of the ocean is more than 20 degrees Celsius.
Potential New Energy Source
A potential new energy source is methane hydrates. These are frozen cages made of water and is filled with methane, which is a natural gas. The drawback of methane hydrates is when extracting it form the ocean bottom, it can be difficult and dangerous.
Global Impact
Offshore petroleum provides 50% of world gas production and 30% of oil production. Methane hydrate deposits provide 10s to 100s of years of energy.
Methane Hydrates Activity
Methane hydrates are found within the permafrost in arctic areas. An increase in average global temperature on sea level and on marine and terrestrial hydrates causes an increase in sea level because the glacial and snow melts. The release of methane into the atmosphere causes an increase in the temperature. When temperature drops the sea level will as well because water is becoming locked into the ice caps. The release of methane into the atmosphere affects falling temperatures because the trend to colder conditions will slow down and possibly reverse. As glaciers slowly advance, sea levels will slowly drop and methane will start to accumulate the air. If the climate warms enough to lead to a significant melting or permafrost, large amounts of methane will be released into the atmosphere. A methane build up will greatly enhance the intensified greenhouse effect that is driving global warming, and could cause the temperature to rise higher and quicker.