le flashlight, or when your driving down a desertedhighway you want reliable tires so you don't get a flat. Therefore reliability is a veryimportant criterion to use when analyzing an energy source. Solar power is reliablebecause the sun comes up every day. It is a fact that sun will come up everyday. These two criteria are very important when evaluating an energy source. Section III.In this section you will be told how the criteria apply to the energy source. Fuelcells are a good energy source because they are environmentally friendly and very reliabledespite being expensive. Fuel cells are environmentally friendly because their waste product is a little heatand water vapor. This shows environmental friendliness because they do not pollute theearth. By not polluting they don't kill plants, which supply people with oxygen. If youtake care of the environment now it will help you later. Fuel cells are environmentallyfriendly because if just 20 percent of cars used fuel cells, we would cut oil imports by 1.5million barrels of oil every day. (Fuel Cells 2000) By cutting that many barrels of oil everyday you would not only save enormous amounts of oil, you would also help theenvironment. By not burning 1.5 million barrels of oil you would not harm theenvironment as much. Big cities would have much less smog if fuel cell-powered carswere used. The U.S. Department of Energy projects that if a mere 10 percent ofautomobiles were powered by fuel cells, regulated air pollutants would be cut by onemillion tons per year and 60 million tons of the greenhouse gas carbon dioxide would beeliminated. (Fuel Cells 2000) This shows that fuel cells are environmentally friendlybecause they would eliminate 60 million tons of harmful gas. Without that harmful gasplants will live longer, supplying people with cleaner air. If we invest our time and moneyin these great machines they will provide us with a very environmentally safe form ofenergy....
