A comprehensive overview of clean energy sources, technologies, applications, and why it matters.
Table of contents:
What is clean energy?
Clean energy, also called green energy or renewable energy, comes from natural resources, such as the sun, wind, water, and earth. These resources are inexhaustible and do not create pollution when they are used. Over the past three decades, the clean energy sector has grown rapidly worldwide due to the benefits of using these natural resources, including climate protection but also achieving a more sustainable development model and economic growth. The clean energy sector includes the production of electricity and heating from renewable sources, such as solar, wind, and geothermal energy. In addition, it includes the use of biomass to produce heat, biofuels (such as ethanol), hydrogen, or biogas. It also includes technologies that help to reduce CO2 emissions in other sectors of the economy, for example, transportation, or that facilitate this process (carbon capture and storage).
What are the clean energy sources?
1. Solar energy: Solar energy is a clean energy source that comes from the sun. Solar panels convert sunlight into electricity, which can then be used in different forms of applications in several industries. Solar energy is a sustainable and environmentally-friendly alternative to traditional forms of energy, such as coal and oil. Solar energy can be used in a variety of ways, from large-scale solar farms that generate electricity for the grid to small solar panels that power individual homes. Solar energy is becoming increasingly popular as more people are looking for ways to reduce their carbon footprint and make a positive impact on the environment.
2. Wind energy: Wind energy is a renewable energy source that comes from the wind. When wind passes by a turbine blade making it rotate at different speeds based on the wind speed itself. This rotation causes electricity generation from the electrical generator connected to the turbines.
3. Hydro energy: Hydro energy is a renewable energy source that comes from the water. hydropower means the use of water to generate electricity. A hydroelectric plant uses the movement of water to propel a mechanical turbine, which converts the kinetic energy into electrical energy.
4. Geothermal energy: Geothermal energy is a renewable energy source that comes from the earth’s heat. The heat from the earth’s crust boils water or other types of liquid turning it into steam that enters a turbine causing it to rotate that will be resulting in generating electricity.
5. Ocean energy: Ocean energy is a renewable energy source that comes from waves & currents. As Wind moves a turbine up in the air well down in the ocean similar turbines are used to harvest the motion occurring from water movement or currents to generate electricity in different approaches or methods, for example, wave generators & tidal generators. All these methods use ocean energy to generate electricity in different ways.
6. Bioenergy: Bioenergy is a renewable energy source that comes from waste like animal & plant waste. Animal waste like cow waste is gathered & added to large digesters that contain bacteria that turns this waste into methane gas. Moreover, methane gas is then used to boil water or other liquids to steam to rotate a turbine & generate electricity. However, plant waste is a much simpler process they take plant waste & burn it to generate electricity.
What is the most used clean energy source?
Around 1,172 gigawatts of installed hydropower plants worldwide rank Hydro energy as the highest renewable energy source that produces electricity globally creating about 16 percent of global electricity in 2012. Scientists have been discussing how to use hydropower for more than two centuries. In 1827, the first dam was built, and by the early twentieth century, they were in common use. However, almost all of today’s hydropower plants were built after 1950. Here are some reasons why hydropower was so popular at that time.
1. It is pollution-free unlike other sources of energy generation at the time, hydropower does not pollute the environment. The water remains clean and clear, and the atmosphere also remains clean.
2. Hydropower is cheap and abundant. Unlike other sources of energy, this one is cheap because it does not have a high cost to start generating power. The average cost of hydropower ranges between 0.02 and 0.03 $/kWh while solar power costs around 0.05 $/kWh and wind power cost 0.053 $/kWh. It is also abundant because we are able to harness the power of most rivers and waterfalls.
What are the applications of clean energy?
Thinking of the applications of clean energy the first thing that will pop up in your mind is using it to produce clean electricity as mentioned above. Well, as clean energy can be generated from several different sources also it can have several different applications, for example, the following:
· Heating: Used to heat water or air which could be transformed through the main heating network to warm up homes or buildings in a nearby village or city to the geothermal geographical location.
· Cargo: Windmills were used to grind grains to form flour back in 1761 also in other parts of the world they would use it to squeeze olives to make oil. In 2020 a Swedish company developed the largest cargo ship to be wind-driven to move cargo from one continent to another changing the logistics business to a greener one.
· Energy Storage: Watermills are also used in a lot of applications like windmills but they were mostly used for rolling in the production process of textile & paper. But nowadays they can even use hydropower in places that don’t have natural running rivers or waterfalls to harvest energy. They rather take still water and pump it up a mountain or a hill to store the water then when they need energy, they let it stream down naturally using the force of gravity that will result in high-speed water spinning the Hydro turbines & generating electricity when needed for the grid.
· Transportation Fuels: Biofuels are one of the clean energy solutions in today’s transportation industry, for example, biodiesel can be used as an alternative to normal diesel to decrease greenhouse gas emissions.
What are the advantages & disadvantages of clean energy?
· Zero CO2 emission: The sources of clean energy are transformed from one form to another without producing any CO2 or greenhouse gases.
· Low running cost: Clean energy generation methods don’t need any kind of fuel it uses free energy in the surrounding environment like air, waves, sun, earth heat, etc.…..
· New job creation: Like every power plant it needs design, simulation, and construction but with different tools & different design approaches which create new demand for specific professions.
· Output fluctuations: Clean energy is free but it is not always available to harvest, for example, in solar energy, the sun is only there for a certain amount of time and then goes away. Other than steam turbines or gas turbines they can work 24/7 seven days a week.
· Set-up Cost: High initial set-up cost due to land buying, mounting structure & paying for the clean energy technology itself which all combined are higher initial costs than diesel generators or fossil fuel based generators.
· Storage Cost: Because of the fluctuations of the clean energy sources & mostly needed when they are not available making the demand for storing energy harvested high which costs a lot when doing projects of mega scale.
When will clean energy replace fossil fuels?
The energy sector is responsible for around 73% of greenhouse gas emissions. One of the main factors is that 2.8 billion people worldwide are using polluting & unhealthy fuels for cooking. In order to combat climate change, the world needs to transition from fossil fuels to clean and sustainable energy systems. Cleaner, more affordable, and modern technologies are rapidly replacing fossil fuels in developed countries but currently support only about 90% of the people in the world. This is why we need to bring energy access to the rest of the world which is around 770 million people mostly in Africa & Asia. To fuel the transition to a low-carbon future, governments must ensure that energy is affordable and accessible for all. This will require investing around USD 70 billion each year in modern technologies that are cleaner. However, Investment alone won’t work an increase in international cooperation between developed & developing countries is needed to share research & development in clean energy & advanced infrastructure for the transmission of energy. All this should be achieved by 2030.
How is the transition to clean energy accelerated?
Government & private sectors including mutual funds are working on providing several financial solutions to accelerate the transition to clean energy through the following:
· Green bonds: debt securities issued to raise capital for projects that are environmentally sustainable. They are new financial tools to finance environment-friendly projects. It is an instrument of financing a project through a public bond offering that contributes to sustainable development. This tool, which is also referred to as green finance, clean finance, or climate finance, is a source of finance that can be used by governments, corporations, and individuals to finance environmentally friendly projects.
· Clean Energy ETFs: Clean energy ETFs are exchange-traded funds that use their money to invest in clean energy stocks, which might include solar energy, wind, hydropower, and geothermal companies. Like other types of funds, clean energy ETFs can easily have a wide range portfolio. ETFs also are much cheaper than mutual funds.
· Carbon Credits: used to help finance clean energy projects by encouraging the reduction of greenhouse gas emissions. Carbon Credits allow companies and individuals who emit CO2 into the atmosphere (such as those who drive cars) to offset their emissions by investing in clean energy or other carbon-reducing projects. The investor receives Carbon Credits which he or she then sells on an international market as part of his or her carbon trading portfolio, therefore receiving financial compensation for reducing their own greenhouse gas emissions through investments in clean energy infrastructure projects across Africa and Asia.
What are the newest clean energy technologies?
1-Green Hydrogen: Green hydrogen is created when water is split into hydrogen and oxygen through an electrolysis process using electricity from renewable energy sources. The hydrogen can then be used to create green energy, such as a combustion process to produce heat energy and electricity, or it can be used to create Ammonia NH3 to be used in the agriculture sector as fertilizers by the chemical reaction between hydrogen & nitrogen.
2-Perovskite Solar Cells: Perovskites, a class of materials that show promise for creating solar panels that could be easily deposited onto most surfaces, are already more efficient than today’s leading photovoltaic materials. These materials would also be lightweight and cheap to produce. Companies looking to harness perovskite potential have to address some remaining challenges before they can be commercially competitive.
3-Sodium Ion Batteries: Sodium-ion batteries are batteries that use sodium rather than lithium. What makes sodium interesting is that sodium batteries are non-flammable, have a higher energy density, work at lower temperatures, more available than lithium & most importantly cheaper by 25% to 30%.
4-Footsteps to Energy: Clean energy now can be generated from footsteps people walking on the subway or in the street can generate energy from just walking this new technology is based on converting the footsteps into a vertical force that can rotate a generator underneath might not generate a lot of energy but the huge number of footsteps daily can definitely generate energy that is enough to power street lights.
Clean energy with all its different sources has been in use for quite a long time but now we have no other choice but to accelerate the transition to clean energy to save our environment. Through adopting new clean energy technologies & innovative clean solutions. So, Governments, Scientists, Investors & Financial institutions should all take action to do what it takes to achieve the goal of going zero emissions by 2030. Hopefully, this November when the COP27 will be taking place in Egypt would result in huge progress & action for the clean energy transition worldwide.
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