Monday, April 18, 2011

Water and Electricity: Perfect Combination??

Hoover Dam
For any kid that has ever played Pokemon in their life, the combination of water and electricity is a no go. Everyone knows that electrical attacks are "Super Effective" against water pokemon, so why would anyone ever want to mix the two??

Hydroelectricity, that's why!! Hydroelectricity uses water to turn a turbine, which then generates electricity to be sent out through transmission and distribution lines to the consumer. As a student in electrical engineering, I had the pleasure of actually touring a Hydro plant up in Boulder, so I have a little more experience and knowledge in this area.

Most hydro plants, including the Boulder Hydro we toured, use gravity to generate the energy to turn the turbine. They transport water from a higher level down pipes using only gravity to build up energy. It then goes through a penstock, which gets narrower as it gets closer to the turbine, increasing the pressure of the water. The water is then forced through a needle valve, which makes the water into a high-powered stream. This stream is what is then used to turn the turbine. At the Boulder Hydro, they used a Pelton Wheel Turbine, which has these buckets all along it that are shaped like two concave ovals welded together, and they have a sharp ridge in the middle of them that splits the water from the needle.



Pelton Runner Bucket
The spinning of the turbines causes electricity to generate through the generators typically connected right to the turbine. This electricity is then transported through a series of step-up transformers, transmission and distribution lines, and step-down transformers to the consumer to be used.

Hydroelectricity is the most widely used form of renewable energy, supplying about 20% of the world's electricity. It's main advantage is that it does not need much fuel to operate, utilizing gravity as mentioned earlier for the main driving force to generate the electricity. Since they do not use any fossil fuels, they also have very low CO2 emissions. The main disadvantage, however, is the reservoir needed from which the water that turns the turbine comes from. This reservoir takes up land which could be utilized for other areas like farming and living, and it also disrupts the ecosystem and animals lives, notably fish.

Overall, I feel that the advantages of hydroelectricity outweigh the disadvantages, and I guess other people think so, too, since it is the most widely used renewable energy, but it's hard to gauge how the changes to the ecosystem will affect the future, so only time will tell if this interest in hydroelectricity will be for the good.

4 comments:

  1. Hydroelectricity is definitely one of the cheaper energy sources once the plant is build, but the main problem with hydroelectricity is that there is not very many places left in the world where we can apply this technology...all the good places are taken and being used.

    Nice Post...fire attack pokemon will destroy electrical attacks!!!

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  2. I have to say I am thankful for the hydroelectricity that we have in this country. Back when they were building the hydroelectric plants though, they definitely were not wanted by a lot of people. Even people like Greenpeace were supporting nuclear power plants in favor of hydroelectric plants. There large ecological impact was a large concern.

    As I understand it now though, we have pretty much tapped into all the efficient hydroelectric power we have here in the U.S. That is the reason we are not building anymore. Unfortunately, hydroelectric power will not be the solution to any future energy demand.

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  3. As Aaron stated, hydroelectric plants take up a significant amount of space and are there to stay when they are built. Drilling rigs occupy space as well during the drilling process. After the process is complete however, often the only thing present is a wellhead which can be confined to an area of 5 square feet. Hydrocarbons poor from that well and produces much larger amounts of energy than water is capable of doing.

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  4. And, to add to the critical comments, it's also possible that significant and prolonged droughts, caused by climate change, will make hydro less feasible in the coming years. But they're definitely elegant, especially when viewed from the air like in the shot you've posted here.

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