DESTINY S.

ALI
ENVIRONMENTAL SCIENCE 1
OCTOBER 20, 2017

How Tides are Turning Our Future

Our world as humans has gone from hunting and gathering to little lights inside a screen

and the whole world open to us without even moving from one spot. Innovation could be

considered commonplace compared to then, and one especially has driven us since the moment it

became available: electricity. Our current society and way of living survives only with electricity,

and there’s no going back to what we once were. Electricity has shaped everything we do to this

very day with the technological advancements that came with it. Our laptops, cell phones,

televisions, the lights in our homes, our heating a cooling systems, irrigation to farms, the

defibrillators in the backs of ambulances; all of them need electricity, and yet, we never think of

where it comes from. So, where does it come from?

Here in the US, our current methods of producing electricity and other energy sources that

we use daily consist up to 64% coal and natural gas, both of which are nonrenewable resources.1

Coal is one of the most environmentally harmful ways of producing electricity with the main

way of collection being mountaintop coal removal. This form of mining is essentially the

complete decimation of entire mountains as the are leveled to reach the coal underneath. The

mining of this coal is detrimental to some of the most basic and important things on this planet;

the water and air. The mining of coal causes serious destruction to the land, completely

destroying forests and wrecking ecosystems. A study in 2010 stated that mountaintop coal

mining has reduced 6.8% of the forests covering the Appalachian mountain range to rubble that

1 https://www.eia.gov/tools/faqs/faq.php?id=427&t=3

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DESTINY S. ALI
ENVIRONMENTAL SCIENCE 1
OCTOBER 20, 2017
can house little to no life, plant or animal. 2 Not only that, but through this mining, toxic metals

such as lead, arsenic, and mercury are leached out into the water supplies, not just hurting the

wildlife in the area, but also becoming dangerous to humans as it comes up through some

people’s drinking water. 3

Essentially, we can’t keep this kind of damage up forever. The current sources we use are

limited, which is why we look towards alternative sources of energy. Tidal energy being a

incredible use of a natural, predictable resources for energy with little to no negative impact on

the environment. Tidal energy works by placing turbines offshore in areas with high tidal

strength, essentially placing a propeller attached to a generator that is spun by the tides moving

in and out to generate electricity. There are a few main methods to harness this energy, the first

ever being a tidal barrage in France. The Rance Tidal Power Station located where the LaRance

river meets the ocean is one such example. Tidal barrages are large dams with series of holes for

water to pass through where there is a turbine which will spin when the water moves. However,

just the amount of force of tides by themselves isn’t enough to turn a turbine, so there are doors

that temporarily cover these ports. Because tides are a regular occurrence due to them being

created by the gravitational forces of the moon and sun, these doors can be opened at precise

times. When the water tide reaches it’s maximum, the doors will open allowing water to rush

through to equalize and effectively turning the turbines creating energy. As soon as the rush of

water stops, the doors are again closed until low tide, when the water can rush back out.

2 Environmental Impacts of Coal article

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DESTINY S. ALI
ENVIRONMENTAL SCIENCE 1
OCTOBER 20, 2017
However, because the doors must be closed in order to put enough pressure to generate

electricity, the barrage can only generate electricity four times a day. 4

Barrages are now not the only way of harnessing tidal energy. A more modern method of

generating tidal electricity is by placing individual turbines, called Marine Hydrokinetic turbines

(MHK), into the water in areas of naturally high pressure to generate electricity.5 These

individual turbines work very similarly to wind turbines in that both turbines will often have a a

set of blades in the same sort of fashion of the propeller of an old airplane directly attached to a

generator and fixed to the ground, but in most cases the sea floor. The Verdant design

implemented in the East River also have methods of turning to face the changing tide,

maximizing the amount of energy to be captured and allowing it to generate electricity

constantly. Compared to the environmental impact of barrages, which is incredibly high by

irreversibly affecting the ecosystem and resulting in buildup of sediments, MHK turbines have

actually been shown to become marine sanctuaries around the base of these turbines and

restoring a lot of the wildlife that had been lacking beforehand from harvesting of scallops on the

riverbed. The intensive observation done on these turbines to ensure they wouldn’t harm the

environment even showed that, while prior calculation showed that fish and mammals would get

caught up in the blades and injured, they actively avoid the blades should they not be capable of

getting past and no strikes have been observed.6

4 Tidal power. (2011). In D. S. Blanchfield (Ed.), Environmental Encyclopedia. Detroit: Gale. Retrieved from http://
link.galegroup.com/apps/doc/CV2644151381/SCIC?u=west66701&xid=4649e3eb
5Smith, T. P. (2013, December). Fish, tides, and turbines: with proper safeguards, water currents can be harnessed
out of sight. Natural History, 121(10), 32+. Retrieved from http://link.galegroup.com/apps/doc/A355938723/
SCIC?u=west66701&xid=17fced9b
6Smith, T. P. (2013, December). Fish, tides, and turbines: with proper safeguards, water currents can be harnessed
out of sight. Natural History, 121(10), 32+. Retrieved from http://link.galegroup.com/apps/doc/A355938723/
SCIC?u=west66701&xid=17fced9b

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DESTINY S. ALI
ENVIRONMENTAL SCIENCE 1
OCTOBER 20, 2017
Now things get to the real question, can tidal power be the solution to our energy problem?

Well, not right now. Tidal energy is relatively new technology compared to solar, wind, nuclear,

and geothermal. Tidal power is capable of 3-3.5% of electricity needs, it just needs to be

harnessed.7 The amount of money and time needed to pass through regulation in the US just to

put prototypes in place is immense, and in some ways moves some states away from that form of

energy production. According to Verdant power, the cost of getting the paperwork together was

more than 50% of the total production costs.8 This issue is the real one holding it back. Tidal

power has incredible capabilities with such little environmental impact, that what really needs to

happen is the shift to be more inclined to it now that some of the research has finally been done

to prove its worth. Tidal energy really is the energy that could start to turn things around.

7Holzman, D. C. (2007). Blue power turning tides into electricity. Environmental Health Perspectives, 115(12), A590+.
Retrieved from http://link.galegroup.com/apps/doc/A173712901/SCIC?u=west66701&xid=47f519ce
8Holzman, D. C. (2007). Blue power turning tides into electricity. Environmental Health Perspectives, 115(12), A590+.
Retrieved from http://link.galegroup.com/apps/doc/A173712901/SCIC?u=west66701&xid=47f519ce

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DESTINY S. ALI
ENVIRONMENTAL SCIENCE 1
OCTOBER 20, 2017

Works Cited

• https://www.eia.gov/tools/faqs/faq.php?id=427&t=3

• Environmental Impacts of Coal article

• Tidal power. (2011). In D. S. Blanchfield (Ed.), Environmental Encyclopedia. Detroit: Gale.

• Smith, T. P. (2013, December). Fish, tides, and turbines: with proper safeguards, water
currents can be harnessed out of sight. Natural History, 121(10), 32+. Retrieved from http://
link.galegroup.com/apps/doc/A355938723/SCIC?u=west66701&xid=17fced9b

• Holzman, D. C. (2007). Blue power turning tides into electricity. Environmental Health
Perspectives, 115(12), A590+. Retrieved from http://link.galegroup.com/apps/doc/
A173712901/SCIC?u=west66701&xid=47f519ce

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