Here are the key points from this section:

• Electricity is generated using the following fuel sources: coal, nuclear, natural gas, petroleum and renewable resources.
• Renewable resources include hydropower (which traditionally makes up over 95 percent of renewable generation), geothermal, biomass, wind, solar, and photovoltaics.
• Coal is popular (51% of Net Generation) because it's cheap and simple.
• Nuclear (20% of Net Generation) is cheapest, but most complicated.
• Natural Gas (15% of Net Generation) is convenient, clean but getting expensive.
• Oil/Petroleum (4% of Net Generation) is expensive, but convenient and easy to use.
• Gasoline and Diesel (0.8% of Net Generation) is relatively expensive, but readily available.
• Hydro power is not really a fuel, so much as a form of potential energy. It is an important energy resource in the global economy. It makes up 9% of Net Generation.
• On a bright, sunny day the sun shines approximately 1,000 watts of energy per square meter on the planet's surface. Solar power represents 0.1% of Net Generation.
• Biomass is "any organic matter which is available on a renewable basis, including agricultural crops and agricultural wastes and residues, wood and wood wastes and residues, animal wastes, municipal wastes, and aquatic plants." It accounts for 2% of Net Generation.
• A pipeline is a series of connected pipes, equipped with pumps and valves and other control devices, for moving natural gas.

Now let's take a look at the Power Grid.