IMPACT of TURBINE ON THE PACIFIC OCEAN

For centuries, tidal devices have been used to harvest energy to meet the needs of various communities. In recent times, with the green revolution concerns over the impact of turbines on oceans has sparked a new debate. In this section of the blog, I will be looking at and evaluating the impact of turbines on marine life.

Tidal energy is a renewable resource that does not result in the emission of pollutants into the atmosphere. Since it does not contribute to acid rain or global warming, tidal energy is thought to be environmentally friendly. When considering installing turbines, the environmental impact on marine life is the overriding issue. The exact impact of this on complex marine ecosystems is not known. Nevertheless, the environmental impacts of tidal energy are expected to be much less than other non-renewable forms of power generation.

Case study

Researchers identified potential problems in the ­­Johnstone Strait, a 110 km channel along the north east coast of Vancouver Island, which is a major migration route for salmon and is home to resident marine mammals notably killer whales. It was uncertain if salmon, which will generally seek out advantageous currents during their migration, would “see”, react and avoid large rotating turbine blades. There was not any particular elevation in the water column which the fish favour over others and which would be used to locate turbines to avoid collision. Researchers concluded that a demonstration unit would provide a much-needed opportunity to assess turbine technology and its environmental effects especially those related to fish and marine mammal impacts. In regards to pollution, since there are no emissions or discharges from these units, marine pollution would be restricted to matters related to leakage of lubricants and the type of paint or coating that the subsurface structures would use to prevent excessive growth of marine organisms. Careful selection of these materials would help to lower the risk of pollution.

The general picture

In this age of growing awareness of the environment and environmental issues, alternative sources of energy have grown increasingly important. The advantages of utilising such energies are given below;

- durability of components

- requires no fuel

- produces no emissions

- produces no waste products during operation

- open sluice, slow-rotor design allows for easy passage of fish and marine invertebrates

- Minimal noise expected during operation

While providing a clean, reliable source of energy, the installation of any artificial device into the environment will affect it in some ways. A number of concerns have been raised about the environmental impacts of wave and tidal devices. Among the most important of these are:

1. Impact on fish and marine mammal movement and/or migration rotors


2. Deflection of local energy regime (as energy is removed by turbines)


3. Marine fouling (encrustation) of energy system components by algae and invertebrates


4. Noise and/or electro-magnetic fields (EMFs) in marine environment

Possible solutions and responses to the concerns

1. Rotors stop at slack tide, protective barriers, sensory braking tech., acoustical tracking technology to guide fish and mammals


2. Energy displacement is NOT expected to be significant


3. Use of non-toxic, anti-fouling materials


4. Noise and/or EMF from operation expected to be minimal

The environmental impacts of any energy scheme should be considered carefully. Based on my research, I believe that the benefits of using turbines far outweigh any negative consequences because there are viable solutions to the impact of turbines on marine life. Tidal energy is the most attractive option because of the small ecological footprint, predictability and modest environmental impact. In comparison to other sources of energy, tidal technology appears to be the most environmentally friendly option.

This factor must’ve been important in Race Rocks’ decision to install turbines, because as it is under the stewardship of Pearson College, it also subscribes to the same values that define the UWC experience.

Undoubtedly, more research should be funded to gain a greater understanding of the potential effects of tidal devices, form a wide range of sources.

www.bluenergy.com/ pdfsOceanBlueEnergy/TidalEnergyPrimer.pdf

UK PARLIAMENT... Select Committee on Science and Technology Seventh Report

http://www.parliament.the-stationery-office.co.uk/pa/cm200001/cmselect/cmsctech/291/29104.htm