Energy is derived from different forms of energy. They are then converted into secondary forms such as fuels and electricity, and then transmitted through different channels to provide power for our homes, automobiles, industries and even our lives. Energy sources are classified as renewable and non-renewable.

Renewable (or clean energy) is energy that comes from natural resources that are continually replenished. Examples include solar, wind, water and geothermal. Fossil Fuels (coal oil and natural gas) are not renewable due to the fact that they form more slowly than we do.

Solar energy can be harnessed in huge solar power plants or a single roof. Solar energy can be converted into photovoltaic power, which creates electricity directly. Water can be used to produce hydropower as well as for energy from tides and waves. Geothermal power comes from underground reservoirs of hot water. Bioenergy is derived from a variety of organic sources, including woody crops, dung from animals and human waste.

Renewable energy is not just environmentally friendly but also cheaper than fossil fuels. Renewable energy is expensive and requires a large infrastructure to harvest and distribute the energy. This can lead to difficult trade-offs when it comes to environmental economic, social, and environmental aspects. Nevertheless, the development of these technologies is growing and they are making progress against more traditional fossil fuels. Renewables could even be cheaper in the long term than oil and coal.