About renewable energy
A renewable energy source means sustainable energy, something that won’t run out and is endless like the sun. Another word used to refer to renewable energy is ‘alternative energy’. It means energy sources that are alternative to the commonly used non-sustainable source like coal.
About zero-carbon or low-carbon energy
Nuclear-generated electricity is not renewable but is zero-carbon which means it’s generation emits very low or no Co2 like renewable energy sources. Nuclear energy has a stable source which means it is not dependent on the weather.
Renewable energy is also referred to as a clean energy and it comes from natural sources or processes that are replenished constantly. For eg, wind and sunlight keep blowing and shining always even if their presence is controlled to some extent by time and weather. Renewable energy is though thought to be a nascent technology but natural powers have been harnessed for a long time for heating, transportation, lighting and more. As we know the wind energy has been used to power the boats to sail the seas and grind grains. The sun has given warmth in the day and has helped ignite fires lasting till evening. But in the past 500 yrs human beings have turned to cheaper and messier energy sources like coal and fracked gas.
The most popular renewable energy sources presently are:–
With the passage of time and advancement of technologies more innovative and less-expensive methods to use wind and solar energy have been known and thus renewables are now the next best power source accounting for more than one-eighth of U.S generation. The renewables are expanding at small and large scales from rooftop solar panels in homes that can sell power back to the grid to giant offshore wind farms. At some places entire rural communities are relying on renewable energy for heating and lighting.
Non-renewable or dirty energy
Non-renewable energy is also called ‘dirty energy’ which includes fossil fuels like oil, gas and coal. Non renewable sources of energy are available in only limited amounts and take a long time to replenish.
Nonrenewable energy sources are typically found in specific parts of the world making them more abundant at a place and not at the other. But on the contrary every country has access to sunshine and wind. If we prioritize nonrenewable energy we can improve national security by reducing a country’s reliance on exports from fossil fuel-rich nations.
But there are many nonrenewable energy sources which can harm the environment or human health. For eg, for the work of drilling oil may require strip-mining Canada’s boreal forest, the technology associated with fracking can lead to earthquakes and water pollution and the working of coal power plants too fouls the air. And all these activities contribute to global warming.
Types of renewable energy sources
Solar energy has been harnessed by humans for thousands of years to grow crops, stay warm and to dry the food items. More energy from the sun falls on the earth in one hour than is used up by everyone in one year. Today we use the sun’s rays in many ways from heating homes and businesses, to warming water or powering devices.
Solar or photovoltaic(PV)cells are made from silicon or materials which change sunlight directly into electricity. The distributed solar systems generate electricity for homes and businesses locally by rooftop panels or community projects. Solar farms can generate power for many homes using mirrors to concentrate sunlight towards acres of solar cells. Floating solar farms or floatovoltaics are used to make use of wastewater facilities and water bodies that are not ecologically sensitive. Solar energy systems don’t produce air pollutants or greenhouse gases and most solar panels have very little environmental impact after the process of manufacturing.
Wind energy accounts for more than 6% of U.S generation and has become the cheapest source of energy in many parts of the country. And we have already been using wind energy from ancient times in the form of wind mills. The top states using wind power are California, Texas, Oklahoma, Kansas, Iowa.
Other alternative energy sources
Hydropower is the largest renewable energy source for electricity in the United States though wind energy will soon be overtaking it. Hydropower depends on especially fast-moving water in a large river or rapidly falling water from a high point and converts the force of that water into electricity by spinning the turbine blades of a generator.
The large hydroelectric plants or mega dams are considered to be nonrenewable energy. The mega dams divert and reduce natural flows not allowing animal and human intervention near the rivers.
Biomass is an organic material that is got from plants and animals and which includes crops, waste wood and trees. On the burning of biomass the chemical energy is released as heat and can generate electricity with the help of a steam turbine. Biomass is mistakenly described as a clean, renewable fuel which is a greener alternative to coal and other fossil fuels for producing higher carbon emissions than fossil fuels. Some forms of biomass energy are also an example of low-carbon option. For eg, sawdust and chips from sawmills that would otherwise decompose and release carbon are a good low-carbon energy source.
An example of geothermal energy is a hot spring. The core of the earth is as hot as the surface of sun because of slow decay of radioactive particles in rocks situated at the center of the planet. On drilling deep wells very hot underground water is brought to the surface as hydrothermal resource which is then pumped through a turbine to create electricity. The geothermal plants have low emissions if they pump the steam and water they use in the reservoir. There are ways to create geothermal plants where there are no underground reservoirs but it may increase the risk of an earthquake.
Tidal and wave energy is in the developmental phase but the ocean is ruled by moon’s gravity which makes harnessing it’s power quite feasible. Some tidal energy concepts may be dangerous for the wildlife like tidal barrages whose working is like dams and are situated in an ocean bay or lagoon. Like tidal power, wave power depends on dam-like structures.
Renewable energy in homes
The sun’s rays can be harnessed to power the whole house at a smaller scale either by PV cell panels or passive solar home design. Passive solar homes are designed to let in sun through south-facing windows to retain the warmth through concrete, bricks, tiles and other materials able to store heat.
Some solar-powered homes generate enough amount of electricity allowing to sell excess power back to the grid. Batteries are an economical way to store extra solar energy to be used at night. Work is under way to make advances on some other products like solar skylights and roof shingles.
Geothermal heat pumps
Geothermal or geo exchange pumps use the constant temperature of the earth to cool homes in summer and warm houses in winter and to heat water.
Geothermal systems can be a bit expensive to install but they are worth the deal. They are quieter, have very little maintenance issues and last longer than the traditional air conditioners.
Small wind systems
We may see that boats, ranchers and small cell phone companies use small wind turbines regularly. Many dealers help site, install and maintain wind turbines for homeowners.Depending on the electricity needs, wind speeds and zoning rules of the area a wind turbine can reduce reliance on the electrical grid.
We being inhabitants of a progressive world should wholeheartedly advocate for renewables and use them in home thereby accelerating the transition towards a clean and proper clean energy future. People should opt for electricity from a clean energy source even if one is not able to install solar panels.
What isn’t a renewable energy source?
Fossil fuels are not a renewable source of energy because they are not infinite. And they release carbon dioxide in the atmosphere which contributes to climate change and global warming.
Burning wood instead of coal is a better option but it too is quite complex. Wood is a renewable source. Wood pellets and compressed briquettes are made from by-products of wood processing industry and thus it is a way to recycle waste.
Compressed biomass fuels produce more energy than wooden logs. On the other hand burning wood, either raw timber or processed waste, releases particles in the atmosphere. Burning wood results in deforestation and the reduction of natural habitats.
The future of renewable energy
The population of the world is on a constant rise and so the demand for energy to power homes, businesses and communities. Innovation and possible expansion of renewable energy sources is the key to maintaining a sustainable standard of energy and protect earth from future climate changes.
Renewable energy sources make up 26% of the world’s electricity today but according to the International Energy Agency(IEA)this percentage is to rise and reach 30% by 2024.It is a pivotal time for renewable energy. In 2020 UK attained a phenomenal renewable energy milestone.
In the future it is expected that the number of renewable energy sources will continue increasing with an increase in demand for power. It will lower the price of renewables.
Renewable energy and it’s uses in homes
There are many advantages of using renewable energy in homely settings and environments.They are—
1.Cuts down electricity bills-After paying for the costs of installing a renewable energy system one can stop bothering about the National Grid and thus reduce the energy bills.
2.Get paid for the generated electricity by you-The UK government’s ‘Feed-in tariff’ pays you for the electricity you generate even if you use it.
3.Sell electricity back to the grid-If one is generating more amount of energy to export some excess back to the national grid then you can receive an added payment from the Feed-in Tariff scheme.
4.Reduces carbon footprints-Green, renewable sources of energy don’t release carbon dioxide or such other harmful pollutants in the atmosphere.