Each decade is marked with increasing environmental concerns due to the negative impacts caused by non-renewable energy sources. Fossil fuels such as oil, natural gas and coal are the commonly used energy sources in most parts of the world; however, these sources are not only harmful to the environment but also subject to depletion.
The need to switch to sustainable energy sources is, therefore, more urgent now than ever. This has led scientists to look for alternative sources of energy while developing and improving the efficiency of the existing sources of sustainable energy. The following are some available sources of sustainable energy.
Solar energy
This is the nuclear fusion power harnessed from the sun’s core. There are various ways of collecting and converting this energy into electricity and other forms of energy. These methods include solar collectors, domestic solar attic fans and use of boilers, mirrors, thin-film solar sheets and photovoltaic cells for direct conversion.
Wind power
The differences in the temperature of the surface of the earth when lit by sunlight causes the atmosphere to move. This movement of the atmosphere causes winds. In the past, the wind was used for pumping underground water. Scientists later developed efficient methods of harnessing this energy using strategically placed wind turbines to create electricity.
Hydroelectric energy
This is whereby the gravitational potential of the water dripping from elevated locations is utilised to turn turbines which generate electricity. It is estimated that hydroelectricity caters for 20 percent of the energy used in the world. Although the hydroelectric installations and power plants are quite expensive to install, they provide a useful and reliable source of sustainable energy, especially for developing countries.
Geothermal energy
Heated steam and water from the earth can be converted into electricity. There are various locations in the world that are suitable for harnessing heat energy from the underground activities and formations, which continue to be replenished by the continuous radioactive decay of elements. Some countries depend on geothermal energy for more than 25 percent of their energy needs.
Biomass
This means using animal waste and plant matter to produce energy. Unfortunately, burning trees for cooking and warmth is one of the popular uses of biomass. However, there are other modern forms of biomass, like methane and alcohol production for fueling automobiles and electric power plants. If used appropriately, biomass can produce amounts of energy with little adverse impacts on the environment.
Other sustainable forms of energy
The thermal energy from the ocean due to the sun’s heat and the energy created due to the movement of tides and waves can be converted into electricity.
Although not strictly renewable, hydrogen and fuel cells are very abundant and can be utilised to provide low pollutant energy. Hydrogen fuel a vehicle through fuel cells or water as the combustion product.