VIDEO 1: What is Energy? (definition of energy and sources of energy mentioned)

What is Energy?

Definition of energy: Energy is the ability to do work, the ability to cause motion and change.
(la energía es la capacidad para hacer el trabajo, la capacidad de hacer que el movimiento y el cambio)

Sources of energy mentioned: what kinds of energy are there? there´s nuclear, mechanical, solar energy, electrical, chemical, radiant, heat, light and magnetic
(¿qué tipo de energía hay? hay energía nuclear, mecánica, solar, eléctrica, química, radiante, el calor, luz y magnética )

VIDEO 2: Sources of energy:

Sources of Energy

a) sources of energy mentioned the book. Their PROS and CONS.

Fossil fuels (coal, oil and natural gas):	Pro: One of the main advantages of fossil fuels is that they are abundant. found in many places and in large amounts. Con: All fossil fuels are essentially non renewable energy sources because nature cannot create enough to keep up with demand. except the natural gas, the fossil fuels produce pollutants.
Hydroelectric power:	Pro: the dams produce a great deal of needed electricity. there are more than 2000 hydroelectric dams in the united states. they produce about 10 percent of the nation´s electricity  and produce,too , about 20 percent off the world´s electricity Con: the flood prevention is good for people, but not so good for the environment. the flooding produces sediments, which is a mixture of gravel, sand and topsoil. when a river is dammed, it cannot renew the soil rich in farmlands located near rivers. the dams also block the route for fish.
Solar energy:	Pro: the solar panel and solar cells produce lots of electricity and heat. since the sun sends abundant free energy streaming toward earth 24 hours a day, people in many parts of the world. Con: the first problem with solar cells is that they are very expensive to manufacture. the second problem is that not all areas of the world get abundant sunlight.
Nuclear power:	Pro: the uranium releases an incredible amount of energy. one kilogram (2.2 lbs) of uranium can produce more energy than 3 million kilograms (6.6 lbs) of coal. Con: many people oppose nuclear power because of its dangers. one danger is the possibility of an accident, a nuclear power plant can´t explode like an atomic bomb however it can have a steam explosion in the core (the area containing the uranium) gets too hot

b) energy sources that do not mention the book.Their PROS and CONS.

Biomass:	Pro: The biomass is a renewable source of energy, can be converted to the other usable forms of like methane gas, or transportation fuels like  ethanol and bio- diesel
Wind energy:
Geothermal:	Pro: energy obtained by tapping underground reservoirs of heat.
Ocean energy:	Capture the energy contained in moving of water.