Negative impacts non- renewable energy has caused. fossil fuels give out carbon dioxide into the air, radioactive energy because mining uranium and then turning it into plutonium takes up a lot of power and releases carbon dioxide in to the air.
5 Questions Q1:How much money does it take to maintain a hydroelectric dam? Hydroelectric dams are temporary features. They will eventually fill up with gravel and silt from the river. This is very expensive to remove. Otherwise the maintenance is things like removal of debris that may damage the turbines. The actual maintenance of turbines and generators is small - occasionally bearings need replacement and so on Q2: How much money does the hydroelectric dam make? about $0.04 per Kilowatt Q3: How long have people been using water power? For many centuries water mills were used to grind corn, but obviously not to produce electricity.Q4: How many water turbines are there in the Hoover dam? there are 17 water turbines inthe Hoover damQ5: Who first used water for energy? Early uses of waterpower date back to Mesopotamiaand ancient Egypt, where irrigation has been used since the 6th millennium BC and waterclocks had been used since the early 2nd millennium BC.
How does Hydropower work? Hydroelectric dams work by converting the movement or falling of water into useful forms of energy such as electricity. Some examples of this are watermills which powered machinery such as sawmills, irrigation which used gravity, and dams which use falling water to power turbines. Hydroelectric dams use a reservoir to create potential energy from the dammed water. This water flows through an intake and into a large pipe called a penstock. The penstock feeds water into a turbine which powers a generator. Many dams will have multiple reservoir tanks which are held at the top of the dam. During low electricity usage the turbines will power pumps to fill these tanks. Then during peak electricity demand the tanks will be dumped onto the turbines to increase their production potential. The dam generator consists of a turbine powered by water flowing through the wicket gate. This gate can be opened more or less to determine the rate of flow through the turbine and thus the amount of power generated. The turbine is attached by a shaft to an electric generator. Hydroelectric dam generators are quite large.
Pros ConsPros and Cons Once a dam is constructed, electricity The high cost of dam construction means that can be produced at a they must operate for constant rate. many decades to become profitable. Dams are designed to last many decades and so can Animals can die because contribute to the they can’t migrate up generation of electricity river or down river for many years / decades. The lake that forms behind the dam can be used for water sports and The flooding of large leisure / pleasure areas of land means that activities. Often large the natural environment dams become tourist is destroyed. attractions in their own right. More money. Pros and cons Hydropower is a fueled by water, so its a clean The building of large dams can cause serious fuel source. Hydropower geological damage. For doesnt pollute the air like example, the building of power plants that burn the Hoover Dam in the fossil fuels, such as coal, USA triggered a number oil or natural gas. of earth quakes. Fish populations can be impacted if ﬁsh cannot migrate The lakes water can be upstream past used for irrigation impoundment dams to purposes. spawning grounds or if they cannot migrate downstream to the ocean.
Bibliography Wikipedia http://en.wikipedia.org/wiki/Hydropower#HistoryWiki answers http://wiki.answers.com/Q/What_are_the_advantages_and_disadvantages_of_hydro-electric_powerRenewable energy index http://renewableenergyindex.com/hydro/how-do-hydroelectric-dams-workGooglehttps://www.google.co.nz/Google pictures https://www.google.co.nz/imghp?hl=en&tab=wi