We use many different types of fuel. This can be a family burning wood or charcoal to cook or heat their houses or using peat, partially decayed plant matter that is burned for cooking or heating in parts of Europe. Of course, fuel can also be coal, oil, and natural gas.
There are different types of coal such as lignite, bituminous, and anthracite (Figure 10.1). As we move from lignite to anthracite, the coal gets harder and burns hotter.
Oil or crude oil is made up of hydrogen and carbon with some other trace elements.
Natural gas is the fossil fuel that burns the cleanest and can be used for energy.
When an energy source is used to generate both heat and electricity, we say it is a combined heat and power (CHP) system or cogeneration.
If we look at Figure 10.2, we can see where oil and gas energy sources are found.
We get energy for electricity from a chunk of coal, or from a gallon of oil or natural gas because these energy items have stored energy, we can turn that stored energy into electrical energy.
When we burn fossil fuels we produce carbon dioxide and water. This carbon dioxide is a contributor to climate change that we will discuss in future chapters.
Another environmental problem of the use of fossil fuels for energy is caused when a method called hydrologic fracturing, commonly known as fracking, is used for extracting it.
We can also split atoms of Uranium-235, in a process known as fission, to produce extremely high heat.
Similar to how electricity is generated from coal, oil, or natural gas, the heat is used to boil water to make steam to turn a turbine to generate electrical energy. Figure 10.4 is a picture of a typical nuclear power plant.
The uranium-235 is stored in fuel rods and the uranium atoms produce radioactivity as the isotopes lose energy.
There have been three times in our history when a nuclear accident happened and radiation was released.
Half-life is a term used to describe the amount of time it takes for a radioactive isotope to be half of its original value.
\