Main topic information
Vocabulary/new concepts:
Non-renewable energy sources are extracted from the Earth’s subsurface, are formed over a very long period – millions of years, exist in limited quantity and are depleted faster than they can be replenished. These fossil fuels are coal, oil and natural gas. Uranium, which is used as fuel in nuclear power stations to generate nuclear energy, is also classed as a non-renewable energy source.
Renewable energy is derived from natural and sustainable sources, continuously replenished naturally and practically inexhaustible. These are called renewable resources – they are sunlight, wind, water, ocean tides, geothermal heat, and biomass. As an alternative to fossil fuels, they offer cleaner technologies and do not emit harmful emissions, reducing air and water pollution and contributing to the conservation of natural resources, biodiversity and climate.
How do we use energy in our daily lives?
- We eat, and for us, food is energy for our bodies to function.
- We use electricity every day to keep us light, and warm, and to operate various appliances and technical devices.
- Energy from burning fuels (gasoline, gas, methane, diesel) powers the vehicles we use – cars, trucks, public transport, trains and planes.
- The various industrial industries, including food processing and packaging, construction, communications, medical equipment, sports facilities and recreational areas – all of these would not function without large amounts of energy.
From what sources can we get energy?
- From traditional fossil natural resources that are depleting over time – oil, coal, natural gas.
- From natural, practically inexhaustible natural resources – sun, wind, water, ocean currents, geothermal heat, biomass.
Interesting fact: Brazil gets a lot of energy to power its cars from plants! Brazilians use sugar beets to make ethanol that can be used to fuel a car, just like gasoline.
The future is about developing new technologies to develop and use natural renewable energy sources – clean energy, called green energy. The way of life of today’s and future generations (charging phones, internet, video games, jobs, living) will depend on green energy.
Look at the story of a poor Malawian boy who, without any formal education in engineering, built a wind turbine from spare materials to power electrical appliances in his home village. This story became known through a TED Talk in 2007 where he shared his experiences. He subsequently wrote a book, “The Boy Who Harnessed the Wind,” which inspired a film of the same name (Netflix, 2019).
The video of the story, with subtitles in 47 languages:
William Kamkwamba’s first wind turbine
Source: https://cs12.pikabu.ru/post_img/2020/12/18/10/1608311265211029173.png
Source: https://cs13.pikabu.ru/post_img/2020/12/18/10/1608311344278414389.png
What does green energy mean and why is it important for all of us?
In recent years, the world has become increasingly aware that traditional energy sources such as coal, oil and natural gas cause significant pollution and contribute to climate change on the planet.
The first serious discussions about the need to look for greener energy sources date back to the 1960s and 1970s, when scientists began experimenting with windmills and water wheels. The term ‘green energy’ came into more prominence in the 1980s and 1990s, but global interest in the subject came in the last 15 years of this century.
The European Union adopts a series of documents to address energy, climate and environmental challenges. Among the most significant are the European Green Pact, the Renewable Energy Directive, the development of national plans with a 2030 horizon, the Trans-European Energy Networks policy, which focuses on connecting the energy infrastructure of EU countries by 2050, and a number of regulations. World Green Infrastructure Congresses are taking place, the last one in September 2024 г.
For further information, you can also view the World Green Infrastructure Congress 2024 report at the following link: https://www.greenroofs.com/2024/09/25/fytogreen-celebrates-major-wins-at-the-world-green-infrastructure-congress-2024/
Green energy encompasses all forms of energy that are produced from natural renewable sources such as the sun, wind, water and biomass. It is a sustainable way of producing energy because it does not deplete natural resources as they are naturally replenished and have minimal impact on the environment.
Why is green energy important to us?
- Reducing pollution and protecting the environment – Energy from coal and oil produces huge amounts of carbon dioxide, leading to global warming and climate change. Green energy, as an alternative to fossil fuel energy, offers cleaner production technologies and is emission-free as it does not emit carbon dioxide, reduces air and water pollution and contributes to the conservation of natural resources, biodiversity and climate.
- Conserve natural resources – Fossil fuels are running out, while sun, wind and water will continue to exist for future generations. They are inexhaustible resources.
- Reducing dependence on external sources and volatile prices – Globally and in the European Union, there is a drive to reduce dependence on fossil fuel supplies from other countries, leading to greater energy independence.
- Stimulating economic growth – Creating the conditions for innovation and technology to make energy production more profitable; creating new jobs.
The energy crisis and climate change are major issues that many nations are dealing with on a global scale. Globally, nations are working to transition to renewable energy sources. This is a result of both scientific advancements and the introduction of cutting-edge technology procedures for the generation of green energy, as well as rising public commitment and awareness.
Nowadays, whole towns in many nations run entirely on renewable energy. This is especially crucial in Europe because the EU has set aggressive goals to lower greenhouse gas emissions and raise the proportion of renewable energy. In addition to safeguarding the environment, such a change opens up new avenues for employment and economic expansion in industries like green technologies and renewable energy.
Examples of green architecture and sustainable buildings can be seen in the following videos:
https://www.youtube.com/watch?v=-dvFb2vC7_Y
https://www.youtube.com/watch?v=bLqAh0IxtaA
https://www.youtube.com/watch?v=-dvFb2vC7_Y&t=6s
Renewable energy sources
Energy is one of the key strategic industries in the global economy. Its future will determine economic growth, social development, environmental protection and our quality of life. That is why investment in the development of new technologies and the transition to green energy are so important and necessary.
What are the main characteristics of renewable energy sources?
- Solar energy
The Sun is the star without which there would be no life on Earth. It is an infinite source of light and heat, a natural source of inexhaustible energy. It is produced by nuclear fusion taking place in the Sun’s core and reaches us in the form of solar radiation. This solar radiation can be converted into electricity!
Every second the Sun emits a huge amount of energy, much of which is light. Every eight minutes, it delivers as much energy to Earth as humanity consumes in a year. Scientists calculate that the energy the Sun delivers in one day could meet humanity’s energy needs for 180 years to come.
How can we make the most effective use of this ecological resource? How can we harness solar energy and generate electricity?
The most common solar energy conversion technologies are:
– photovoltaic panels (PV cells) – provide direct conversion to electricity. They are made up of multiple solar cells that generate an electric current when they absorb light;
Solar panels are most cost-effective in locations where there is a lot of sunlight. They can be combined in different numbers and sizes according to specific needs and installed on the roofs of buildings. They can also be used to power devices such as calculators and clocks!
Source: https://st.depositphotos.com/1001686/4981/i/600/depositphotos_49813625-stock-photo-solar-panels-under-sky.jpg
– solar collectors – devices that absorb the heat energy of sunlight and transfer it to a liquid (water or antifreeze solution) that circulates through the collector. They are widely used for domestic water heating;
Source: https://st.depositphotos.com/1003525/4992/i/600/depositphotos_49929031-stock-photo-vacuum-collectors-solar-water-heating.jpg
– concentrating solar energy – mirrors or lenses are used to direct and concentrate reflected sunlight at a specific point, which is converted into high-temperature heat. This is then generated into pressurised steam that drives a turbine to generate electricity.
Source: https://st5.depositphotos.com/1068875/66183/i/600/depositphotos_661833500-stock-photo-aerial-view-solar-plant-seville.jpg
The application of these technologies is best suited to locations with a lot of sunlight and does not involve the generation of electricity at night. We are therefore faced with the challenge of developing efficient systems for storing the energy thus acquired and stimulating the development of new energy technologies.
- Wind energy
Wind is created by the movement of air masses from areas of higher atmospheric pressure to those of lower pressure. This is caused by the uneven heating of the Earth’s surface by the Sun, with warmer air rising and colder air rushing in to replace it. This creates air currents – wind.
Winds, whether permanent, periodic or local, affect every part of the Earth. They can be used as a renewable source of energy. Wind turbines (wind turbines) are built to capture the wind’s energy and convert it into electricity. These facilities can be placed in any location where there is a lot of wind. If more wind turbines are built, we talk about wind farms. Some are on land and some are offshore – they are called ‘offshore’ wind farms.
How to harness wind energy and generate electricity?
The direction and intensity of the wind affect this process. Therefore, picking a good spot for the wind turbines is crucial. The wind drives the rotation of the turbine blades. A generator receives this rotational motion and uses it to create electricity. Power lines carry the generated electricity to substations, where it is delivered to customers.
Despite the undoubted advantages of wind energy, there are also some negatives to note, such as the impact on wildlife and especially birds – they can collide with turbine blades during migration or in low visibility, they can change their natural habitats, and the vibrations of the structures in the ground can affect their behaviour. Involving experts and ornithologists in the planning and construction of wind farms would largely prevent these problems.
Source: https://st2.depositphotos.com/1935459/9006/i/600/depositphotos_90062914-stock-photo-wind-power-plant.jpg
- Hydropower (hydroelectricity)
Hydropower – often called the energy of water. It is one of the most familiar sources of energy where the power of moving water is used to generate electricity. As early as about 2000 years ago, humans invented the waterwheel to produce power to drive simple mechanisms, e.g., to grind grain. At the beginning of the 19th century, the first water turbines appeared, mainly used for irrigation. Later, hydroelectric power plants (HPPs) were built to produce electricity.
Hydropower is a renewable natural resource due to the periodicity of the water cycle. It is highly efficient, as much of the energy of water is converted into electricity (water has a density of up to 800 times that of air and even a small flow of water can produce significant amounts of energy).
Other important advantages are:
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- the ability to regulate the flow of water – automated control systems are used for this purpose, monitoring the water level in the dams and the amount of water needed for power generation, irrigation and flood protection;
- the ability to change the power generated according to the needs of the power system;
- long service life and low maintenance of hydropower facilities.
How to harness water energy and generate electricity?
To ensure the operation of hydropower plants, it is necessary to build dams where large quantities of water can be retained and stored. In them, water is collected from the bed of rivers and streams. This collected water is allowed to escape through pipes from the dam, creating a powerful jet that turns a turbine. This in turn is connected to a generator that produces electricity.
Source: https://media.gettyimages.com/id/1229617869/photo/honduras-weather-tropical-storm-iota-dam.jpg?b=1&s=594×594&w=0&k=20&c=nfq56A93ed0t8VLY2K8H2G9ofPOghn4__FJlTdKb1Cw=
Source: https://p0.pikist.com/photos/466/762/water-pipe-full-pipe-flowmeters-hydroelectric-power-station-pipes-line-pipeline.jpg
Hydropower from rivers has a significant share in the overall renewable energy mix. However, many countries are reluctant to build new such facilities because the construction of dams leads to some environmental problems – changes in the natural water regime, induced landslides and erosion, loss of biodiversity in the area and disturbed habitats for plant and animal species. The social aspect is not to be ignored either – the obliteration of some settlements, the displacement of their population, the loss of possible cultural values, etc.
Hydropower will continue to play an important role in the energy mix of the future. The use of new technologies, careful planning and the search for responsible environmental solutions will contribute to the sustainable development of this important energy resource.
One possibility is to harness the energy from sea and ocean waters, from tides. New research in this area shows that this energy could meet up to 10 per cent of the world’s electricity demand. The first tidal power plant (TPP) was built in 1966 in France. Similar plants are operating in South Korea, Germany, Russia, Norway, China and Canada.
LINKS and additional information:
https://www.youtube.com/watch?v=T4xKThjcKaE
