Thirty years ago, it was hard to imagine that there could be any other source of energy that could efficiently supply power. ... Also, it costs less than other technologies. ... Typically, they are dams across the mouth of a river that connects into the ocean. Tidal barrages first allow water to flow into the bay or river during high tide, and release it back during low tide. ... Placed inside the ocean, the duck "bobs" up and down along side the waves. ...

• Word Count: 1431
• Approx Pages: 6
• Has Bibliography
• Grade Level: High School

Just as the world isn't black and white, the issue on fracking has more than two sides to the issue. ... That causes contamination to the water like that in the Ohio River. ... The air emissions from the drills, trucks, and other machinery coming in and out of fracking zones have also increased the ground level ozone. ... The arguments for both sides are compelling, but the environment doesn't need yet another problem to deal with. ...

• Word Count: 1506
• Approx Pages: 6
• Has Bibliography
• Grade Level: High School