Have you ever wondered where your electricity comes from? How does your car use gasoline to run? What about the impact of these things on our environment or how we will continue to produce them? As a country, we need to start looking to the future and planning for what's to come. Currently, 86% of America's energy comes from oil, natural gas and coal. All these resources will run out sooner or later. We need renewable energy sources that continue to produce cleanly and efficiently for a long time. Before we commit to an idea and fully realize it, we need to compare all the different energy sources available in the United States and choose the best one for everyone. Electricity is the flow of electrons at high speed. There are two types of electricity, AC and DC. Alternating current, also known as alternating current, is electricity supplied to residential areas. AC is also used in radio and audio currents. AC current is when the flow of electrons occasionally changes direction. Direct current, or direct current, is the electricity used in batteries. Direct current is when an electrical current goes directly to the source. Electricity can be measured in two different units. One is volts. A volt is the amount of pressure that electrons are subjected to when they move. The other unit of measurement is amperes, commonly known as amps. An ampere is the number of electrons passing through the wire per second. 1 ampere equals 1 mole or 6.02 x 1023 electrons per second. Another common term used when talking about electricity is resistance. Resistance is how hard it is to push electrons through a wire or how much they resist. The negative end of a battery or anything with poles is what provides the ele...... middle of paper ...... ants are usually placed in rivers or lakes where the flow of water is constant. If the river flows downstream and the plant is located at the foot of the hill, the water pressure will be much greater, producing more energy. Hydroelectric power plants can be used wherever there is a reservoir or river large enough to finance a power plant. They are financing with low, consistent costs that can be added to county taxes. However, if there were ever a severe drought in which rivers and lakes dried up, the hydroelectric plant would be useless. Another concern is damage to aquatic life. The current from the dam can make it difficult for fish to swim upstream to spawn. This would mean that fish ladders would have to be installed in areas highly populated with fish. Furthermore, although hydroelectric plants are low cost once built, like any power plant, they are expensive and timely to build.