Well, renewable energy sources are wind and hydro. They will never run out. Nonrenewable energy sources are coal. Nonrenewable energy sources are fossil fuels. The similarities are that most of them have a relation with the sun. A nonrenewable energy source and a renewable energy source are similar in the way some of them are used to transform energy (you cannot create energy, it can only be transformed from one energy to another.) The similarities are few but there are many differences, most of the positives are on the renewable energy's side.
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