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1. Biomass (Wood, forest and agricultural wastes, domestic sewage, industrial waste) 

2. Solar Energy (Photo-voltaics and Solar Thermal) 

3. Wind Energy (wind turbines)

4. Hydro Power (Rivers, waves and tides) 

5. Geothermal Energy (This is the energy trapped from the heat inside the earth) 

Water is also a renewable resource, as is wheat, rice, potatoes and other crops.

Through the process of photosynthesis, plants capture the sun's energy. When the plants are burnt, they release the sun's energy they contain. In this way, biomass functions as a sort of natural battery for storing solar energy.In general there are two main approaches to using plants for energy production: growing plants specifically for energy use (known as first and third-generation biomass), and using the residues (known as second-generation biomass) from plants that are used for other things. The best approaches vary from region to region according to climate, soils and geography.

Solar energy applies energy from the sun in the form of solar radiation for heat or to generate electricity. Solar powered electricity generation uses either photo-voltaics or heat engines (concentrated solar power). A partial list of other solar applications includes space heating and cooling through solar architecture, day lighting, solar hot water, solar cooking, and high temperature process heat for industrial purposes.

Airflow can be used to run wind turbines. Modern utility-scale wind turbines range from around 600 kW to 5 MW of rated power, although turbines with rated output of 1.5–3 MW have become the most common for commercial use; the power available from the wind is a function of the cube of the wind speed, so as wind speed increases, power output increases dramatically up to the maximum output for the particular turbine.Areas where winds are stronger and more constant, such as offshore and high altitude sites, are preferred locations for wind farms.

Energy in water can be harnessed and used. Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy. There are many forms of water energy: 

Hydroelectric energy is a term usually reserved for large-scale hydroelectric dams.

Micro hydro systems are hydroelectric power installations that typically produce up to 100 kW of power.

Run-of-the-river hydroelectricity systems derive kinetic energy from rivers and oceans without the creation of a large reservoir.

Geothermal energy is from thermal energy generated and stored in the Earth. Thermal energy is the energy that determines the temperature of matter. Earth's geothermal energy originates from the original formation of the planet (20%) and from radioactive decay of minerals (80%).The heat that is used for geothermal energy can be from deep within the Earth, all the way down to Earth’s core – 4,000 miles (6,400 km) down.