We can reduce carbon footprints by using renewable energy. It even starts with the smallest things. We do not have to convert our whole home into solar energy in on night but start small every day. For My Algebra class. My TI-83 calculator is solar powered instead of using a battery. Another energy we can use is wind energy. energy.gov says It's a clean fuel source. Wind energy doesn't pollute the air like power plants that rely on combustion of fossil fuels which is a pro. But right now it is very expensive because the amount of wind power is limited. If one person a day can start using wind power, it will become cheaper because it will be produced more.  We can all start by doing something small right now. There are 7.4 billion people in the world. Only one person is needed to start change.