Renewable energy sources are energy sources from the persistent or natural flow of energy from our immediate environment. These include hydropower, bioenergy, direct solar energy, geothermal energy, wind energy, ocean energy, and nuclear fission energy.
The continuous surge of energy requirements across the globe is unsurprising. This is because the demand for energy and its related services to meet the needs of social-economic development, manufacturing, health, and welfare of the population is also constantly rising. While the earth cannot change in its form, it is now a challenge to look for ways to sustain the increasing demands of energy for future generations while mitigating the effects of climate change.
So, this is where renewable sources of energy come into action. These sources could be the solution to lead the future of energy consumption. Let us get to know these renewable energy sources which will more likely be the biggest sources of energy in the future.
Hydropower is an energy source coming from the movement of water from a higher elevation to a lower level by turning turbines to generate electricity. This includes Dam project with reservoirs, in steam projects, and run-of-river. The technologies of hydropower are technically mature. However, the projects utilized through this means vary temporarily.
The primary energy is given by the height of the water where the water falls down on the turbine and gravity. The technical annual potential of hydropower generation is 14,574TWh with a projected capacity of 3,712 GW. However, the installed capacity of hydropower across the globe is lesser than its projected potential. Only 50% of hydropower installed capacity is found in Brazil, Canada, China, and the US. The resource probability of hydropower could be affected by climate change. Although it only accounts to be less than 1%.
The main advantage of this energy source is that it doesn’t produce greenhouse gases. Plus, it can be upgraded quickly and can store energy for many hours. (Hanmann, 2015) However, the utilization of the sites would require artificially creating reservoirs which lead to flooding. The hydroelectric structures largely affect the ecology of the river’s body by disturbing the ecological continuity of fish migration and sediment transport and inducing a change it its characteristics.
This energy produced by bioenergy comes from biological sources. This can be an important source of energy for electricity generation, cooking and heating, and transport using biodiesel. The electricity from bioenergy draws a wide range of different sources such as agricultural residues like sugar cane waste, forest by-products like the wood residues, and animal husbandry residue like the dung from a cow.
One significant advantage is that the by-product or residue of this energy source is fuel. Significantly, it doesn’t contest between land for fuel and land for food. Presently, the production of biofuel is still comparatively low but is continually increasing (Ajanovic, 2011)
The utilization of biological components for energy production is still a major concern. This is because the public is worried that the food produced will be utilized to provide energy. Another concern with bioenergy is that it can worsen soil conditions and degrade vegetation due to overexploitation of forest, water overuse, and exceedingly exhaustive forest and crop residue removal (Robertson et al., 2008; Koh & Ghazoul, 2008). However, with proper management on the production of bioenergy, it can also enhance biodiversity, improved soil productivity, and increase carbon in the soil.
This renewable energy source directly draws energy from the sun. The solar energy technology is taken from the sun to produce electricity from concentrating solar power (CSP) and photovoltaic (PV) to sustain direct lighting needs, produce thermal energy, and create fuels that can be used for transport or other purposes. As per the World Energy Council, the total energy from the radiation of the sun is 7,500 times more than the world’s total primary energy consumption of 450 EJ in a year (Urban and Mitchell, 2011).
One of the leading renewable sources of energy is wind. This is because wind exists everywhere and even in considerable density in some places. The energy from the wind exploits gets kinetic energy from moving air. The production of electricity from large turbines onshore offshore helps mitigate climate change as the turbines help convert wind energy into electricity.
The use of wind energy has increased over the years, with a 10% annual increase in its installed capacity. But, this has to be supported with a dispatchable generating capacity because of its intermittency and low utilization.
Waves are made when wind passes over the body of water. The faster the speed of the wind, the vaster distance the wind travels, the more prolonged the wind is sustained, the greater the wave height, and the greater the energy produced. The ocean stores enough energy in the forms of wave, tidal, and temperature gradient. The first-gen of commercial ocean energy devices was first installed last 2008 in the UK-SeaGen and Portugal- Pelamis.
This renewable source of energy is derived from the earth’s interior. The origin of the heat is associated with the earth’s internal structure and all the physical processes occurring therein. Even if heat is present in large amounts in the earth’s surface, it is rarely concentrated, unevenly distributed, and often too deep to be exploited manually.
Heat is taken from geothermal reservoirs. Hydrothermal reservoirs are permeable and have naturally adequate heat. While reservoirs that need hydraulic stimulation to reach optimum heat are called enhanced geothermal systems. Once taken from the surface, these fluids can then be used to generated electricity or other purposes that may need the use of heat energy.
With the increasing demands of energy, it is high time for leaders to utilize renewable sources of energy that can be used to harnessed more energy while protecting our planet from the harmful effects of climate change. This will hit two birds with one stone – increasing source of energy while mitigating the effects of climate change in the world.