Photosynthesis is a very important method of capturing and storing solar energy. Sunlight provides the energy plants use to convert carbon dioxide, water and nutrients into chemical energy that is stored as sugars, starches and cellulose. Plants use this chemical energy as food. We use the resulting biomass for food, clothing, building materials, and as feedstock for many chemical processes. All of the petroleum we use today from natural gas and crude oil is the result of photosynthesis.
Today, we produce ethanol and biodiesel from plant materials such as corn, soybeans, sugar cane and a few other crops. Researchers are continuing research to find efficient and economically viable methods to produce ethanol from cellulosic materials such as switchgrass, wood debris, etc.