1. Tidal Energy By: Kathryn Cora Hinderaker, Allison Marie McFarland, Taylor Catherine Wahlberg & Skip.

2. How it Works A huge dam is built across a river estuary. When the tide goes in and out, the water flows through tunnels in the dam. The flow of the tides can be used to turn a turbine Kathryn Hinderaker 1

3. Renewable or Nonrenewable? Yes, tidal energy is renewable because tides will always flow Kathryn Hinderaker 2

4. Cost of Tidal Energy The cost varies greatly depending on where the dam is built The cost ranges from millions to billions of dollars The Severn Estuary cost almost 37 million dollars Once built no cost except low maintenance cost Skip 3

5. Pros of Tidal Energy Non-polluting to the environment Once built, it is free Tides are very reliable One tidal plant after being placed can produce energy for 75 to 100 years Ali McFarland 4

6. Cons of Tidal Energy Environmental and marine safety issues Very expensive to build Limited geographically, few places are suitable for tidal energy It provides power only for 10 hours in a day Ali McFarland 5

7. Environmental Concerns Can cause a build up of pollutants 15% of fishes that swim through will be killed The salinity of the basin will decrease Too much phytoplankton would grow Skip 6

8. Major Countries FRANCE -240 MW tidal barrage (largest) CANADA - 20 MW annapolis tidal barrage CHINA -11 MW tidal power scheme TAYLOR CATHERINE WAHLBERG 7

9. USAUSA  ALASKA 620twh/y  WEST COAST 250twh/y  EAST COAST 160twh/y

10. Citations “Tidal Energy.” 27 February 2012. http://www.darvill.clara.net/altenerg/tidal.htm. “Ocean Tidal Power.” 9 Feburary, 2009 http://www.energysavers.gov/renewable_energy /ocean/index.cfm/mytopic=50008. “Tidal Energy.” 4 April 2012 http://library.thinkquest.org/06aug/02365/tidal. html. “Energy Resources: Tidal Power.” 4 April 2012 http://www.darvill.clara.net/altenerg/tidal.htm.