<human>:  What is renewable energy and how does it work?
<bot>: Renewable energy is energy obtained from sources which can be naturally replenished over a short period of time, such as wind, solar, biomass and hydropower. Renewable energy is obtained by harnessing the energy of the sun, wind, surface/groundwater, plants, and geothermal heat. Solar energy is created when sunlight is collected and converted into usable electricity. Wind energy is produced when the air is captured and converted into mechanical power. Biomass is created by burning organic waste, such as wood, agricultural waste, and industrial waste, to produce heat and electricity. Hydropower is generated when falling water is captured and converted into electricity. Geothermal energy is captured from the heat of the Earth's core. Renewable energy sources are considered to be more sustainable, reliable and cost-effective than non-renewable sources of energy.