(HAO) Humans and Oceanography Introduction Lesson

Humans and Oceanography Introduction

The ocean contains a large amount of energy. If we can find ways to harness some of this energy, it could provide a means of sustainable energy.

Ocean Waves and Tidal Power

A tidal barrage is a dam built across the mouth of a bay and turbines are mounted in the structure. Water is held in the bay or out of the bay until there is a significant enough difference in water level that will force water in and out of the running turbines. Incoming tides flowing through the turbines generate power.  

image of tidal barrage; tidal turbine, sea level, current, and seabed

This is only feasible in about 30 locations worldwide, however. This could also negatively affect bay environments, which are often nurseries for commercially important fish. It also changes the hydrology of the bay, restricts the passage of fish, and changes the habitat for birds and other organisms.

Ocean-thermal energy conversion (OTEC)

uses temperature differences between shallow and deep ocean water. It uses a low-boiling point liquid, like ammonia, to vaporize and turn the turbine and spin the generator to make the electricity. Cold ocean water is pumped up from the deep ocean and re-condenses the ammonia vapors.   Currently, this technology is only experimental.

OTEC image includes: Sun Electricity Drinking Desalinated water OTEC Warm water Cold water Irrigation Cold-water discharge Mariculture Nori Kelp Phytoplankton Zooplankton Abalone Clams Oysters Lobsters Shrimp Salmon Steelhead trout Cold-water refrigeration Building air conditioning Air-conditioning

Wind Energy

This category of renewable energy has increased 28% per year and meets 1.5% of our global electricity demand. It is thought that wind power could supply as much as 12% of the world's electricity by 2020.

wind turbine image: Horizontal Blades catch the wind and spin Generator converts mechanical energy into electricity Cable carries electricity to transmission line Computer system controls direction of the blades Wind Machine

Wind turbines are wind-driven generators and wind farms can have up to several thousand turbines. These turbines turn the metal coil of the generator to generate electricity.  

image of windfarm in the ocean

The amount of energy produced depends on the location of the turbines, the radius of the blades, and the height of the tower. We are building wind farms offshore in the ocean. Oceanic winds are dependable and strong and do not require the purchase of land.

Unfortunately, wind power is intermittent. If it is not windy, you aren't generating any electricity and some areas do not have enough wind to make wind power economically feasible. Some people also complain about the looks of wind farms and the can be a hazard to birds because some birds have run into the spinning turbine blades.

Image reads Oceanography

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