| There are indeed many forms of alternative energy, | | | | electrical generator. Wind farms can provide a lot of |
| and, with the effects of pollution and global warming | | | | a community's electrical needs. |
| becoming more evident and widespread, we need to | | | | The pros of wind energy are that the wind is free to |
| look to these alternative energy forms as a way to | | | | harness; no pollutants are produced. |
| ease the threat posed by pollution and global | | | | The cons are that the availability of wind is |
| warming. | | | | unpredictable; mechanical failure is a possibility;wind |
| We're doing a better job of harnessing alternative | | | | towers are an eyesore, as are wind farms. |
| energy sources as more governments worldwide | | | | Geothermal |
| introduce legislation and financial measures to help | | | | Heat is produced from rocks under the earth heating |
| increase the implementation of these sources. But, | | | | water. Holes are drilled in these areas, which release |
| there's still a lot of work to be done, as so much | | | | steam jets that are used to drive turbines that |
| more energy goes to waste than we are able to | | | | produce electricity from generators. |
| harness. | | | | The pros are that the plants can soon become |
| Let's take a look at the various forms of alternative | | | | self-sufficient and are small enough to have little or |
| energy and the benefits they bring us. | | | | no effect on their surroundings;if carefully managed, |
| Solar Energy | | | | no pollutants are produced. |
| The sun supplies more energy in one day than is | | | | The cons are that pollutants can be produced if the |
| used by the entire planet in one year. So, despite the | | | | geothermal energy is not controlled;poor drilling can |
| fact we're starting to see solar energy being | | | | cause toxic gases to be released;energy supply may |
| harvested more, there's still a lot more energy | | | | run dry. |
| available to us. Solar energy can be harnessed in | | | | Hydroelectricity |
| various ways. We'll examine the most common. | | | | Hydroelectricity is produced from water pressure |
| - Photovoltaic technology uses small amounts of | | | | being released to power wheels or turbines that run |
| silicon that react with the sun's light to generate a | | | | generators to supply electricity. Dams are the most |
| small electrical charge. Solar panels are built from cells | | | | obvious example of this, although the power of tides, |
| made up of silicon and semi-conductors. | | | | also known as tidal energy, is also used to generate |
| - Solar thermal utilizes solar collectors to heat water | | | | electricity. |
| or air, which is then passed through a conductor such | | | | The pros of hydroelectricity are that the amount of |
| as piping to supply heat to the required destination, | | | | power generated can be controlled;water is |
| such as a swimming pool. | | | | reusable;it's pollutant-free;as long as water is available |
| - Passive solar can be as simple as opening drapes to | | | | producing sufficient pressure, power can be |
| allow the sun's energy to heat a room, or as | | | | generated continually. |
| complicated as designing an entire building to | | | | The cons are that dams are large and expensive |
| incorporate thermal mass to facilitate heat storage | | | | projects; if the water dries up, so does the power |
| and distribution. | | | | supply;a shortage of suitable locations. |
| - Parabolic mirrors are used to produce steam, which | | | | As can be seen from the above, there are many |
| in turn provides thermal heat. | | | | forms of alternative energy but these are probably |
| The pros of solar energy are that the sun provides | | | | the most common. The good thing is that we're |
| abundant light and heat, all free;no pollutants are | | | | beginning to take more advantage of these as we |
| produced;there are few or no moving parts, so these | | | | work on reducing our reliance on the rapidly dwindling |
| systems are virtually maintenance-free. | | | | supply of fossil fuels. |
| The cons are that the sun is not always available; | | | | As these technologies are improved, they will |
| some of the technology is expensive;a lack of | | | | become cheaper to install, making them more readily |
| knowledge of solar technology is preventing more | | | | available to more people. And we've barely scratched |
| speedy and widespread acceptance. | | | | the surface of what's possible, with the future only |
| Wind Energy | | | | being limited by our imagination. There's a massive |
| The wind is harnessed using wind towers. The wind | | | | amount of free energy out there waiting to be |
| turns the blades on the tower, which, in turn, power | | | | tapped; we just need to figure out the best ways to |
| either machinery (in the case of a windmill) or an | | | | tap into it. |