Free 800 words essay on Renewable Energy Sources for school and college students.
In this Anthropocene epoch of humanity, climate change has become the most apprehended and disquieting phenomenon of planet earth. With an unprecedented increase in erratic weather conditions, catastrophic natural calamities, melting of glaciers, decreasing agricultural productivity, worsening air quality, and scarcity of fresh water sources have started raising constant alarms. One of the biggest reasons for such perpetually debilitating scenario is human’s overdependence on fossil fuels for energy generation. This unsustainable practice has been emitting a colossal amount of greenhouse gases that cause global warming. These anthropogenic factors can be taken under control by gradually shifting towards sustainable or renewable sources of energy, which needs no external replenishment and is non-polluting in nature.
The sources of renewable energy predominantly are solar, wind, geothermal, ocean, biomass, and hydro energy. Unlike their renewable counterparts, these forms of energy will not dwindle and are not environmentally degrading. Promising technological breakthroughs are being developed worldwide to harness the tremendous potential of these unconventional sources of energy.
Solar Energy: The sun which is 90 miles away from earth offers a powerful source of energy for our planet. It has been calculated that enough sunlight falls on earth every hour to meet the energy needs of the world for an entire year. Solar cells are used to harness sunlight and convert it into electricity, using photovoltaics and concentrated solar power. A standard photovoltaic panel is made of silicon cells. The methods that offer solutions are solar heating, solar photovoltaics, solar thermal electricity, and solar architecture. Solar energy that hits one square mile of the earth in a year is equivalent to 4 million barrels of oil. This technology has a plethora of opportunities in research and development, manufacturing, and installation. A solar energy system can produce electricity for the entire day if the solar electric modules are combined with batteries in one integrated energy system.
Wind Energy: Wind is basically atmospheric energy in motion, which gets its energy from solar radiation that is differentially absorbed by earth surface converted through convective processes due to temperature differences to air motion. The uneven terrain of earth modifies the wind pattern and this motion energy is harvested by wind turbines to generate electricity. Turbines use wind to rotate its blades and use propeller blades which turn the spin shaft attached to a rotor that generates electricity. Wind energy is the least expensive of all forms of alternative energy and completely clean, abundant, and non-polluting.
Biomass: The main sources of biomass are agriculture, forests and industrial waste. This is also an alternative sustainable fuel that can deliver a significant reduction in carbon emissions. Technically, biomass includes grass, leaves, wood, wood chips, rice husk, peanut shells, sugarcane fiber, sewage, etc. Biomass extraction creates more space by removing waste from landfills. It helps a generation of biofuels and mitigates carbon footprint. Biomass is affordable as present in abundant supply.
Geothermal Energy: This exceptionally clean source of energy is basically heat from the earth that has to be converted into power. The heat that produces the steam and water that power geothermal systems are eternally renewable and sustainable. Since the extraction of this energy doesn’t involve expensive mining, it is far less destructive as compared to fossil fuels. Geothermal energy is pulled from earth’s crust, mantle, outer and inner core. This heat is originally produced naturally radioactive minerals such as potassium and uranium, volcanic activity, and solar absorption. Hot springs and natural geysers are examples of this intense pressure of heat. Specific technologies that are used to tap geothermal heat are dry steam power plants, flash steam power plants and binary cycle power plants. This energy can also be directly used for climate control in buildings, by a process called direct heating by heat pumps. Geothermal energy can be used to heat greenhouses, de-ice roads, improve oil recovery processes, and even in spas and health clinics.
Tidal Energy: Oceans are said to be the biggest carbon sinks that help sequester millions of tons of carbon produced by anthropogenic means Tidal energy is a form of hydro energy that uses a large amount of energy present in oceans. Tides are created by the gravitational pull of both sun and moon at regular intervals. Tidal energy has great potential worldwide and the largest sources are the US, UK, Norway, and the Mediterranean. The motion of tidal water has an immense amount of kinetic energy present in it, in form of tidal currents or tidal streams. The movement of sea water is harnessed to rotate turbines and generate hydroelectricity. This technology with high-predictability employs tidal barrages that provide protection against flooding and land damage.
Investments in renewable energy technology have seen a sharp rise in recent years as the world is gradually shifting towards alternate fuel. Although the demand for energy and power are never going to decline, alternative mechanisms have to be implemented that reduce carbon footprint and control the incessant and dangerous global warming.