One astronomical unit or 150.4 billion meters away—that is the distance between the sun and the earth. This is said to be just the right expanse that enables life to survive in this planet. Just a little closer and our seas would dry up, move a little farther and temperatures would drop ice-cold. Every living thing owes its existence in part due to the energy that the sun produces.
Humankind has harnessed the sun’s power over millennia. Our ancestors realized it early that the sun drives natural processes to work.
Due to its great necessity, many civilizations have used the sun as inspiration in works of art, music, and religion. It is also one of the first objects of curiosity that inspired the development of science and innovation.
Solar energy is the energy created by the sun. Today, perhaps the most practical use of the sun is harnessing solar energy. It occurs through nuclear fusion or when two hydrogen atoms collide in the sun’s core and fuse to produce a helium atom. This process creates tremendous amounts of energy.
At its core, the sun fuses about 620 million metric tons of hydrogen continuously. This process is the same in every star in the universe. This combustion of tiny atomic particles generates energy and heat until eventually the stars run out of hydrogen to use.
In stars bigger than our sun, energy is created by the CNO cycle. CNO is derived from carbon, nitrogen, and oxygen which is used to convert hydrogen to helium. Only a fraction or roughly about 2% of the sun’s energy is formed through the CNO cycle. Our sun uses the PP cycle or the proton-proton chain reaction.
The energy created by these cycles is released through space along with heat and light in the form or electromagnetic radiation or EMR. These are waves and particles where most of it is invisible to the naked eye.
The energy that reaches earth can be used to power our houses, cars, offices, and basically everything else that uses electricity. Technologies developed on Earth can convert the energy generated light-years away into useful electricity.
How is solar energy converted into electricity?
Solar energy can be harvested for consumption as usable energy through solar energy technologies. These include photovoltaic cells, concentrated solar energy and other solar architecture.
There are two methods in capturing solar radiation and converting it to electricity. These are the active solar energy technology and the passive solar energy technology.
Active solar energy technology is the most common method. It uses electrical or mechanical devices to convert energy into another form which is either heat or electricity. Passive solar technology does not use any devise but relies on the climate of the place to heat buildings and structures during winter while reflecting heat in summer.
The most common active solar energy technology is the photovoltaic which is found in solar panels. Photovoltaics are the powerhouse unit of every solar panel. It is usually made out of silicon, which is an element rich in Earth.
As the sun shines on a solar panel, energy is absorbed by the photovoltaic cells which create electrical charges. The solar rays excite the electrons in the PV cell. The electricity generated is a direct current. This can be translated to an alternating current through the use of an inverter.
The alternating current electricity then runs through electrical panels of a building, house, structure, and whatnot. This can now power appliances, gadgets, lights, and every imaginable device that uses electricity.
Most solar panel technologies come with batteries to store the excess solar energy. This can be used to power during nighttime.
Solar energy: advantages and disadvantages?
The foremost advantage of solar energy is its being a renewable energy. We practically have an unlimited supply of sunlight. Scientists have estimated that the sun’s life is up to another five billion years. Sunlight is also steady and stable that makes it very reliable.
It is also a clean source of energy. It does not burn chemicals and compounds that are harmful to health and the environment. It does not release greenhouse gases to the atmosphere. Climate change scientists recommend adopting clean sources of energy like solar power to drastically slow the tide of global warming.
In places which receive high amounts of sunlight like the tropics, people could take advantage of solar power where it is the practical choice. Solar energy can also reduce costs in the long run and stop reliance from electricity provided by big oil companies.
Homes can save more money when there is an excess of solar power generated. This could be sold to energy providers or to anyone in need of back-up power source.
The major disadvantage of using solar energy, however, is the cost in installing the solar power technology. Equipment is expensive and require special knowledge and tools in proper installation.
In the certain countries, there are only a few services which provide solar panel installation. It might also require an almost permanent structure to install it with. Not many poor residential areas can benefit from solar energy when settlements are only temporary.
Natural factors such as climate and access from the sun are also important considerations. Sunlight must be consistent and abundant for it to be efficient. Thus, not everyone can use solar power technology.
Is solar energy renewable?
Solar energy is one of the renewable and cleanest sources of energy. Its source is sunlight which is practically limitless. Unlike fossil fuels which rely on the actual amount of fossilized carbon matter in the ground, solar energy has a steady and unrestricted supply.
The sun’s hydrogen supply is also estimated for another five billion years. It does not use up any resource here on Earth for solar energy to be produced. It simply relies on the sun’s own supply of hydrogen.
It also does not need complicated processes to produce electricity. It does not rely on external factors or intervention for the energy to be produced which makes it self-sustaining.
Among the other forms of renewable energy, solar energy is the most accessible. Some sources rely on special conditions like wind energy which can only be harnessed in high altitudes or naturally windy areas or geothermal energy where can only be found in specific parts of the world.
Solar energy on the other hand is almost everywhere since wherever the sun shines, solar energy can be harnessed.
Solar energy does not produce pollutants or greenhouse gases which are threats to humanity. It does not have environmental impacts that cause tremendous harm in people’s health and our climate.
How is solar energy produced?
While we have covered how solar energy is converted into electricity, there are other ways to produce solar energy. Concentrated solar energy is another method of harnessing solar power.
It uses lens or mirrors to concentrate sunlight into a smaller area. The concentrated radiation heats a fluid which can generate electricity or fuel another process.
Solar furnaces and solar power towers are examples of this. Solar furnaces use the same normal process of concentrated solar energy. Solar power towers use flat mirrors which follow the sun’s arc as it moves through the sky.
A tower is arranged with mirrors and in turn reflect light into a concentrated ray which shines on a focal point. The focal point is a container of water which when it heats create steam that powers a turbine.
Recent developments have used liquid sodium which has a higher heat capacity and heat retention. It can continue to boil and generate power even when there is no sunlight.
Solar architecture is a kind of passive solar technology which uses special kinds of material and genius architectural and design techniques which absorb heat and light
during the day and distributes it to the use of the home or structure instead of letting it dissipate and go back to the atmosphere during the night. Some of these techniques is painting the roof with a light color, installing barrier, or roofs with vegetation.
Uses of Solar Energy
Solar energy has a variety of human application. Solar energy is primarily used today to power up homes and residential areas. People can save a lot of resources in departing from traditional energy source.
It can provide a steady supply of electricity to power heavy appliances and can even be used at night due to the use of a battery.
Some cultures use solar ovens which is a simple device that is DIY-friendly. It uses common materials and can cook food almost as fast as a traditional oven. It is also recommended by NASA as a survival tool plus it’s a cool scientific experiment that can be taught to kids early.
Solar energy is also used in heavy industries to protect pipes from corrosion. Some airports and other power demanding services are also using solar energy to augment electrical supply.
Water heating is also a common use of solar energy. It can be used to heating swimming pools, home water systems, and water for cooking which can lessen reliance on non-renewable energy source.
Solar energy is also used in lighting systems. Cities around the world use solar-powered street lights that are sustainable and budget- friendly especially in rural areas where there is no reliable electricity.
Solar power remains to be one of the most reliable and accessible sources of energy. Our dependence upon the sun cannot be underestimated. It sustains life in this planet. It powers our homes, our schools, and our industries. It also drives innovation and human progress.
We should take advantage of its limitless abundance to help reduce the effects of climate change and also help poorer communities by providing access to electricity.
Governments should provide incentives to people to encourage more to adopt renewable sources of energy. We should also support funding in research and development to make solar energy technology cheaper and affordable to more people.
Adopting solar energy technology can also provide green jobs which will cut our reliance in big oil companies who continue to pollute our environment. There should be wider access to information regarding solar energy technology.
Let us hope that more people adopt solar power as primary source of energy. May the recent developments in solar power technology open the floodgates to affordable and free access to natural resources for the collective benefit of the whole. It should
continue to propel new technologies and applications of this abundant resource to improve our lives. The potential remains to be vast and the future should warm and excite us.