Examples of Renewable Energy

Wind

Wind is an amazing natural phenomenon in which air is moved across our globe. This is a renewable resource that will always occur so long as we have our Sun to warm the face of the Earth. The reason that the Earth has wind at all is due mainly to this uneven heating by the Sun which leads to differences in pressure in our atmosphere (6). As we have come to learn, nature does not like imbalance e.g. where one area has a higher pressure while a relatively nearby area has a much lower pressure. The wind is nature's entropy increasing, or its desire to have disorder in this system, as two areas of equal pressure is better than two of very different pressures (2).

This movement of air occurs very commonly in some places, but not nearly as frequently in others. Two common areas to have wind are nearby mountains or nearby large bodies of water such as the ocean. Wind coming from living near mountains occurs because during the day the mountain will gather more heat and thus wind will be blowing up the mountain side from a lower level town below. But during the night, this process switches as the mountain cools, leading to wind blowing down the mountain side and through the town. The oceans work in a similar way, the town is heated during the day leading to winds being blown from the ocean to the warmer land. At night, however, this process changes again as the ocean becomes warmer than the town (as water holds heat better than air) and the wind blows from the town towards the ocean (9).

Courtesy of: http://www.edinformatics.com/math_science
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Solar

From the previous two examples, we can see that the Sun drives much of our resources used for alternative energy. The Sun warms our Earth to allow for life to survive as without the Sun, Earth would be far too cold to have promoted life to the levels that we have seen today, as we can see with other planets in our solar system such as Neptune. We could also have been too close to the Sun, leading it to be much too hot to harbour life here on our planet, much like Mercury or Venus. Our distance away from the closest star in the sky is the reason why so much of the events on Earth can take place!

The Sun, like all stars, is a gigantic fusion furnace in that it is a super heated sphere of elements that are combined in a process called "fusion" to produce elements of larger atomic number from elements of smaller atomic number. There is a large amount of energy that is given off by this process, which is actually a result of some of the mass of the original two atoms being changed into energy. If you were to look on a periodic table, you would notice that for example, hydrogen, an atom of one proton and one electron in its natural form, when combined with another hydrogen atom creates helium if they are capable of fusion (things like temperature, speed, and distance apart affect this). Helium is actually lighter than the original two hydrogen atoms combined, and it is from this difference in mass, that the energy is produced from a fusion reaction. The Sun contains huge amounts of hydrogen in different isotopes such deuterium and tritium, and can also fuse helium-3 to create a stable isotope of helium and giving off a single proton in the reaction to continue this massive chain reaction. This energy travels millions of miles to reach us here on Earth in the form of charged solar winds and electromagnetic radiation such as human visible light (2).

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Water

Water is an incredible substance that without we could not live. Our bodies are composed mostly of water (more of water than any other substance) and we are told to drink a given amount per day to replenish the amount that we actually sweat out over the course of the day. For those that don't know, water is a compound of two different kinds of elements, one being hydrogen and the other oxygen, or H2O. Another reason why water is so amazing is that unlike many other compounds, water actually is at its most dense before it becomes a solid, it is at its most dense at about four degrees Celcius meaning that it will sink when at this temperature. This is why ice that forms actually floats on top of the water, as this ice is actually less dense than the water around it (2).

Much like wind, water can be considered a renewable resource thanks to the Sun. Our Sun heats water around the globe, leading to storms and rain fall that replenish rivers, reservoirs, and glaciers. It is from this cycle of water evaporating from lower regions such as the oceans and being distributed to higher areas such as mountainous regions or rivers that we are capable of having steady flowing rivers (9). Below is an example of a waterfall in a river which is powered by this process:

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