Introduction to clean energy
Clean energy. Renewable energy. Green energy.
There’s so much hype about these topics, so we decided to create a simple, concise and easy-to-understand introductory guide to clean energy.
Clean energy is a really hot topic these days due to the ongoing and devastating effects the fossil fuel industry has on climate change.
Clean energy is one of the important solutions to a sustainable future on planet Earth. It is both cheaper and cleaner to produce than energy from coal and other fossil fuel sources.
What is clean energy? How do we produce it? What is the future of clean energy? We’ll explore these questions and more.
Let’s dive right in to the fascinating and exciting world of clean energy!
What is clean energy?
Clean energy is energy that comes from renewable sources that don’t emit pollutants into the air (such as carbon) and is good for the environment.
You may have heard the term “zero emission” before. Zero emission refers to energy sources that do not produce pollution. CO2 is a form of emission that occurs naturally but when there is too much of it in the atmosphere, the earth warms as a result of the greenhouse effect.
The Greenhouse Effect is similar to a greenhouse in a garden or nursery: heat from the sun is trapped in the greenhouse creating a warm environment inside the greenhouse.
This happens on a planetary scale when heat from the sun, which is usually reflected back out into space, is trapped in the atmosphere due to too much pollution such as carbon dioxide (CO2) and methane.
The more carbon dioxide in the atmosphere, the more heat gets trapped in the atmosphere. This results in a planet that keeps getting hotter and hotter. Increased planetary temperatures have significant effects on the weather. These changes in weather patterns is called climate change. Climate change is resulting in flooding, fires, rising sea levels, crop failures on farms and many other negative effects.
The key to solving this problem is for humans to stop using energy sources (such as oil, coal and other fossil fuels) that pollute the air with carbon dioxide and focus on clean energy.
There are some subtle differences between clean energy, renewable energy and green energy.
Clean energy is energy that is produced without polluting the Earth.
Let’s look at what renewable energy and green energy are.
What is renewable energy?
Renewable energy is energy that is constantly being replenished. As soon as one bit of energy is used, there’s another bit waiting in line. The sun and wind provide never-ending energy. These are the most common forms of renewable energy.
Is nuclear energy renewable? The energy in atoms is used to create energy in a nuclear power plant, and although the energy in atoms is virtually limitless, the materials used to create this energy (such as uranium) is not renewable. As a result, nuclear energy cannot be regarded as renewable energy.
Renewable energy doesn’t require constant materials to keep the power flowing. Coal, oil and natural gas are not renewable energy sources because there are limited coal, oil and gas reserves on earth. When these reserves become scare, the price of energy goes up. When these reserves run out, the lights go out.
Earth has plenty of renewable energy sources available in the following forms:
- Wind energy: the air on planet Earth is constantly moving with great force. This energy can be captured in the form of wind energy through wind turbines and windmills
- Solar energy: the sun is a constant form of energy, producing solar heat energy and solar electric energy (through the photo-electric effect produced in solar panels)
- Hydropower: water flows with great power and the power from waterfalls, dams, tides, waves and currents can be captured through hydroelectric turbines and watermills
- Geothermal energy: there is plenty of heat and energy inside the Earth’s crust – this can be seen when a volcano violently erupts! Geothermal springs are a milder way to capture energy from inside the Earth and power electric turbines
What is green energy?
Green energy comes from nature. Sources of green energy do not create pollution and do not create the greenhouse effect. Green energy sources do not add carbon dioxide and methane into the atmosphere.
Most renewable energy sources can be considered “green”. These include energy from sunlight, wind and water – although if a hydroelectric dam is built and as a result destroys an existing ecosystem or causes a river to stop flowing in certain areas, this cannot be considered to be “green”. Green energy is energy that is produced while taking care of the environment, society, animal and plant life and the entire ecosphere.
No form of energy is perfectly green (even solar panel production have an environmental impact) but the goal is to produce energy in the most environmentally friendly way possible.
How does clean energy work?
Clean energy works when energy is produced in an environmentally-friendly way. Clean energy is produced without negative by-products such as carbon dioxide, nuclear waste, methane or other pollutants. These pollutants can create devastating effects on the environment including climate change as a result of the greenhouse effect.
Clean energy results in few or zero by-products. Solar and wind energy are examples of clean energy: no by-products are created when solar or wind energy is produced. This is unlike coal or petroleum energy which results in massive amounts of pollution in the form of CO2, methane and other pollutants which enter the atmosphere and cause the greenhouse effect.
Why is clean energy so important?
Clean energy is important for the continued life on planet Earth. Humans require energy for survival and to maintain civilisation. The more complex our civilisation, the more energy we need.
Unfortunately the energy we currently use is mostly very bad for the environment and is causing extreme weather through climate change. The fossil fuel industry which pollutes the atmosphere and creates the greenhouse effect (and thereby global warming) is currently the main source of energy on the planet.
It is important for humans to move towards using clean energy instead of fossil fuels so that the effects of global warming can be reduced. If climate change is not reversed there is a very real chance that humans and other life forms will die as a result of severe weather, flooding, fires and destruction of food crops.
Clean energy is therefore very important for the future of life on Earth.
What are the benefits of clean energy?
Clean energy is critical for the future of life on Earth.
Clean energy has the following benefits:
- It is cheaper to produce clean energy than fossil fuel energy
- Clean energy does not pollute the environment
- Clean energy does not cause the greenhouse effect and global warming
- Clean energy is freely available and renewable
- Clean energy production has no by-products such as CO2, methane, nuclear waste and other pollutants
Is clean energy really clean?
Yes, clean energy is really clean. This means that when clean energy is produced it does not create pollution. There are no harmful chemicals or gasses produced when clean energy is made. Clean energy is good for the environment.
How can we get clean energy?
The clean and renewable energy industry is growing significantly, thanks to the warnings from climate scientists and economists who have foreseen that there is no long-term future for fossil fuels on planet Earth.
Clean, renewable energy can be produced by governments, companies and individuals.
Political pressure is important to cause governments to move towards clean energy. Most governments receive donations and financial support from the fossil fuel industry who want to maintain their position.
Government policy is influenced by these donations (or bribes) and as a result clean and renewable energy does not get implemented at the necessary speed, if at all. The more pressure society puts on government the faster the move will be towards clean and renewable energy.
Many companies are now operating in the clean energy industry and as a result there is more competition. Competition lowers prices for consumers and therefore it is now cheaper than ever to install solar panels, wind turbines and other forms of renewable energy for your home.
Individuals are also making the move towards clean and renewable energy and are learning how to set up solar panels, wind turbines and water energy for their homes, farms and businesses. People who can are buying electric vehicles and changing their lifestyle towards walking or cycling instead of using cars. Hikers and campers use solar backpacks to charge their mobile devices instead of relying on fossil fuel energy.
A culture of greed results in overuse of energy. We constantly want more and more. This puts great pressure on the economy and power systems of the world. As a result, our greed will create more and more pollution and climate change.
Changing attitudes, lifestyle changes and pressure on governments will help reduce the reliance on fossil fuels and the move towards renewable energy and a simpler lifestyle.
What are the types of clean energy?
Clean energy (which does not produce any harmful by-products while it is being produced) comes from various sources.
The most popular forms of clean energy are:
- Solar: heat energy from the sun is converted into thermal energy in solar heaters, and light energy from the sun is converted into electrical energy through the photo-voltaic effect in solar panels
- Wind: wind energy is converted into mechanical and electric energy through mills and turbines
- Biomass: energy from decaying organic plant matter is turned into heat energy used to drive electrical turbines
- Hydropower: energy from moving water is used to turn water turbines and mills to create mechanical and electrical energy
- Geothermal: heat energy directly from the Earth is converted into electrical energy by heating water which produces steam that turns electricity-generating turbines (or smart energy exchange through a geothermal heat pump system)
These forms of energy are renewable, never-ending and clean: no harmful by-products are produced.
Sun energy is vast and renewable. Massive amounts of energy from the Sun enter the Earth’s atmosphere daily and can be harnessed in various forms.
Solar energy is radiation energy from the Sun and can produce heat and produce energy. Solar energy is so massive that scientists predict that the Sun can produce more energy than the Earth’s population will need now and in the future.
Solar energy is both renewable and clean. This makes it ideal as a solution to the ongoing climate crisis caused by the fossil fuel industry.
Thermal energy from the Sun is collected and used in various ways including solar geysers, solar stoves, solar heating plates and solar ponds. Black materials absorb the heat from the Sun and various containers, heating tubes and other designs are used to capture thermal energy from the Sun.
Mirrors or shiny surfaces focus the heat from the Sun and are used by solar cookers and concentrating solar power plants to cook food or produce electricity.
Electrical energy from the Sun is produced by the photo-voltaic effect which occurs when light energy strikes certain materials, exciting their electrons and then generating an electrical charge. This is how solar panels produce electricity.
Solar panels used to be expensive but the price has dropped significantly in the past 10 years. Solar panels are now cheaper and more efficient which means that many businesses, hospitals, government departments, farmers, military installations, households and factories are relying more and more on solar power.
Wind energy is produced with moving air turns a windmill or wind turbine. This energy is converted to mechanical or electrical energy. Wind energy simply requires the wind to blow, and since the atmosphere is constantly in motion wind energy is regarded as renewable energy. Wind energy also produces no by-products or pollution and is therefore regarded as clean energy.
How do wind turbines work?
Wind turns blades (which look like propellers on an airplane) and these are connected to a rotor. The rotor turns an electrical generator and therefore wind energy is converted into electrical energy.
Wind energy is slightly more complicated than solar energy because moving parts are required during the process of converting wind energy to electrical energy. Moving parts require lubrication and maintenance and this can be a nuisance although technology is developing quickly to improve the quality and lifespan of wind turbines.
Micro wind turbines (also called small wind turbines) are used by individuals to power low-energy devices such as laptops and smartphones.
Large wind farms are an array of large wind turbines which produce large amounts of electricity for a town or city.
Wind turbine design is fascinating and engineers are constantly looking to design more efficient wind turbines. These are either vertical axis turbines or horizontal axis turbines, each with its own advantages and disadvantages.
Wind turbines can be installed on land or even at sea where the wind blows more fiercely. These turbines are massive, very tall and transported by ship.
Wind turbines and windfarms produce massive amounts of energy which are added into the national power grid.
Hydroenergy converts energy from moving water into mechanical or electrical energy. The watermills of the past are an example of hydroenergy. Modern hydroelectric dams are significant sources of energy for many countries.
Hydroelectric dams are created to use the energy from a flowing river to turn electrical turbines which generate electricity for the grid. These hydroelectric dams can have a significantly detrimental effect on ecosystems and communities, especially if rivers are diverted or dams created to disrupt existing habitats.
Hydroelectrical systems should be designed to have as little environmental impact as possible.
There are different forms of hydro energy, as follows:
Conventional hydroelectrical systems produce electricity as a result of the natural flow of a river, tide or sea current that moves electrical turbines. Water can also be stored in dams or reservoirs and released to power electrical turbines.
Gravity hydropower (or pumped-storage hydropower) is when water is pumped into a tank or reservoir higher than the electrical turbines. Gravity causes the water to flow down past the turbines which turn to generate electricity. Farmers often use this technique as an alternative to electricity from the grid. The power required to pump the water back up to a higher elevation means that this system is not self-sufficient but it is used to offset costs or if the grid is unreliable.
Most households will not have access to a flowing river, waterfall or other moving water source, so this form of clean, renewable energy is mainly used by governments and farmers.
Geothermal energy is the heat that exists within the crust of the earth. This energy is vast because the inner core of the Earth is as hot as the surface of the Sun!
People have used geothermal energy for thousands of years for both cooking and heating. Think also about the hot springs that exist for relaxation and health treatments.
Modern geothermal energy plants are created by drilling deep into the Earth to harness the geothermal energy within the Earth to heat steam and drive electrical turbines and heat pumps. Due to the massive scale of these projects, this is done by companies or governments and not by individuals.
Geothermal energy is much cleaner and cheaper than energy produced by fossil fuels.
The future of energy
What do scientists and economics predict about the future of clean energy?
There are some current trends that show the way of the future. Let’s explore some trends in energy that we will see developing over the next few years:
- The good news is that clean, renewable energy is predicted to grow significantly in the next decade
- Solar energy will continue to become cheaper as the price of solar panels, inverters and batteries continues to decline
- Solar, wind, geothermal and biomass energy will be rolled out in scale across developed countries
- Developing countries are already showing green shoots of renewable energy growth and this will continue as government policies change away from fossil fuel alliances
- Distributed generation instead of centralised generation of electricity
- Smart grids will allow electricity generation to be fine-tuned and optimised across the grid, reducing waste
- New systems for storing electricity from variable sources (sun and wind) will become more important
- Power-to-X will convert surplus electric power to other useful forms such as mobility, heat, chemical processes and more
Renewable energy is the most exciting part of the future and a massive trend across the planet right now. People are starting to realise that we cannot continue to pollute the Earth and cause climate change with old energy systems.
Fossil fuels are becoming even more scarce. Scarcity and greed result in war, inflation and corrupt government policies.
A change in lifestyle, attitude and outlook is required to transform the world to clean, renewable energy. This process has already started and it is the future of energy on Earth.