1. Tidal energy By: Anna Gibson and Morgan Gimblet APES 3/23/2016

2. The scientist You are concerned with understanding and explaining how this energy source works. Here are some questions you will want to consider for your presentation. 1. What is the source of power or raw materials for this energy source? A form of hydropower that converts the energy obtained from tides into useful forms of power, mainly electricity. 2. How does the system harness and transfer energy? Tidal energy is produced through the use of tidal energy generators. These large underwater turbines are placed in areas with high tidal movements, and are designed to capture the kinetic motion of the ebbing and surging of ocean tides in order to produce electricity. 3. What are the by-products from this energy source? It is a clean energy source, which has no waste products and is virtually inexhaustible. 4. Is it possible to use this energy source in our area of the country? No, it is being used in places such as France, Canada, China and Korea aka places near water. According to http://www.darvill.clara.net/altenerg/tidal.htm it states that there are only 20 foreseeable places for tidal energy. Tidal Energy is reliable as tides are uniform and predictable to nature. However, such devices can run to be rather expensive. http://www.darvill.clara.net/altenerg/tidal.htm

3. The Environmentalist You are concerned with the effects of this technology on nature. You want to explain how this new project could impact the natural surroundings. You would ideally want to see technology that will not produce greenhouse gases and that will not consume natural resources in such a way that would adversely affect future generations of both humans and other species. Here are some questions you will want to consider for your presentation. 1. Are there any harmful wastes produced by this technology? Tidal energy systems that use dams may restrict fish migration. These dams may also cause silt to build up along the dam. 2. Will natural habitats be adversely affected by this technology? Yes, it may restrict fish migration, causing habitat changes forr the aquatic life and well as for birds that may rely on low tides to unearth mud flats that are used as feeding areas. 3. Are there any concerns to public health and safety? Not for human public health or safety, no. 4. How will using these energy resources contribute to global warming? While estimates for life-cycle global warming emissions for wave and tidal power are preliminary, published research suggests that they would be below 0.05 pounds of carbon dioxide equivalent per kilowatt-hour.. To put this into context, that’s literally nothing.

4. The economist You are concerned about how much the technologies will cost. You want an energy source that is both efficient and cost effective, something that will give a return on the initial investment to put the technology in place. 1. How does the cost of this energy source compare to the current cost of fossil fuels in this area? Coal: total cost=10.29 cents per kilowatt hour Nuclear: total = 3.31 cents per kilowatt hour Natural gas: total = 8.09 cents per kilowatt hour Solar: total = 18.12 cents per kilowatt hour Wind power: total = 3.45 cents per kilowatt hour Free- Flow Tidal Current (Underwater Wind Farm):total = 7 - 10 cents per kilowatt hour 2. How much money will it cost to start to use this technology? As an example of the cost of setting up, a proposed 8000 MW tidal power plant and barrage system on the Severn Estuary in the UK has been estimated to cost US$15 billion 3. How much money will be saved by using this technology over the long term? There is not enough information to tell because the technology is so new 4. Does this technology create any extra employment opportunities? Yes this creates job opportunities

5. The Historian You are concerned with how this energy source has been used around the world. Humans have always used energy to improve their quality of life. Many different types of energy have been used in different regions and at different times in history. Here are some questions you will have to answer in your presentation. 1. When was this energy source first discovered or invented? The earliest evidence of the use of the oceans’ tides for power conversion dates back to about 900 A.D. Early tidal power plants were typically used for grinding grains into flour. Power was available for about two to three hours, usually twice a day. 2. Where in the United States or other countries is this energy source currently used? There are very few commercial-sized tidal power plants operating in the world. But there are locations in France and South Korea. There are none in the U.S. since there are only a few sties where tidal energy can be produced at a reasonable price. But, places like China, England, China and Russia have a major potential for using this type of energy.

6. 3. How easily do you think our community would accept using this new energy source? It would not be practical for San Antonio because the technology is too new and because we are far from the ocean, it would be difficult to transport the energy. 4. How much energy is currently produced using this technology? For wave energy, one estimate is 2,000 terawatt-hours per year, and tidal stream power—which uses ocean currents to drive underwater blades in a manner similar to wind power generation—in shallow water can generate some 3,800 terawatt-hours per year 5. How has this technology affected the lives of the people who use it? There would not be much of an impact on society because this would take place in the middle of the ocean.

7. How it works