Energy
Chapter 2 - Society
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Welcome to the Energy page
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| Please watch this movie |
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| Fossil fuels still supply 80% of our energy. And people point to this number to say it's impossible to switch to renewables, especially if we want to do it quick enough to stop climate change. But their argument overlooks just how much energy we waste – and how we could do it better. |
| https://www.youtube.com/watch?v=EVJkq4iu7bk |
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Core ideas
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Energy is the ability to create change.
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Energy exists in how objects interact with each other, but
Entropy, not energy, makes the world go round
We start with the most fundamental physical laws: Energy is not the principle. It is the parttern. Entropy is the principle.
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According to Carlo Rovelli, there is just one basic equation that points to an arrow of time: the second principle of thermodynamics, which says:
- entropy is constantly increasing
- the journey from order to disorder is down a one-way street.
We observe this journey because heat flows towards the cold things and one day, all the heat will dissipate, and we will experience neither the past nor the future.
"What makes the world go round is not energy, but sources of low entropy."
We don't live by inhaling heat but by eating food, a source of low entropy that releases energy by digesting, transforming food into a higher entropy state.
| Content source |
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| The Order of Time - Carlo Rovelli - Penguin Books - 2018 |
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Entropy is not the same as energy
Do not confuse energy with entropy.
Let's consider fossil fuels, charcoal, oil, and even gas. They possess a high potential energy level and are in a low entropy state. They are the remaining of the even lower entropy state of the photons we receive from the sun. When we burn those fuels, we get heat. This is what we call energy because, for a short time, we can transform it into steam, electricity, motion, etc.
In the process,
- we decrease the usable energy (the global oil stock)
- and pump heat and chaotic particles into the earth's atmosphere.
In practice, any self-sufficient system also receives energy from somewhere 'beyond' its system boundary. A simple real-world example is the rainfall cycle: water evaporates from the sea or land surface to form clouds, from which rain falls and returns to the sea via streams and rivers. The cycle relies on energy from the sun to power the evaporation that drives the seemingly counter-entropy 'upward' part of the cycle.
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Key take-aways about entropy
- The entropy of a physical system is proportional to the quantity of energy no longer available to do physical work
- Entropy is the measure of change from order to chaos
- Low entropy means a high potential energy
- High entropy means a low potential energy
- Entropy creates our notion of time
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Key take-aways from the earth entropy/energy management
- The difference between the low entropy energy from the sun and the high entropy radiated into space gives us the possibility of 'energetic work on Earth'
- Blocking outgoing infrared radiation (entropy) stores more and more (not very useful) energy in the Earths atmosphere
- Our main problem is to capture the low entropy solar energy and transform this into useful energy forms
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Energy on earth
Energy is the ability to do work
Scientists define energy as the ability to do work. Modern civilization is possible because people have learned how to change energy from one form to another and then use it to do work. We use energy for a variety of things, such as walking and bicycling, moving cars along roads and boats through water, cooking and refrigerating food, lighting our homes and offices, manufacturing products, and even sending astronauts into space.
There are many forms of energy:
- Heat
- Light
- Motion
- Electrical
- Chemical
- Gravitational
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Energy is grouped into two general categories for doing work:
- Potential, or stored, energy
- Kinetic, or working, energy
Energy can be converted from one form to another. For example, the food you eat contains chemical energy, and your body stores this energy until you use it as kinetic energy during work or play. The stored chemical energy in coal or natural gas and the kinetic energy of water flowing in rivers can be converted to electrical energy, which can be converted to light and heat.
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Energy sources are renewable or nonrenewable
The many different sources of energy, can all be divided into two categories:
- Renewable energy sources
- Nonrenewable energy sources
Renewable and nonrenewable energy sources can be used as primary energy sources to produce useful energy such as heat, or they can be used to produce secondary energy sources such as electricity and hydrogen.
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Potential energy
Potential energy is stored energy and the energy of position.
Chemical energy is energy stored in the bonds of atoms and molecules. Batteries, biomass, petroleum, natural gas, and coal are examples of chemical energy. For example, chemical energy is converted to thermal energy when people burn wood in a fireplace or burn gasoline in a car's engine.
Mechanical energy is energy stored in objects by tension. Compressed springs and stretched rubber bands are examples of stored mechanical energy.
Nuclear energy is energy stored in the nucleus of an atom—the energy that holds the nucleus together. Large amounts of energy can be released when the nuclei are combined or split apart.
Gravitational energy is energy stored in an object's height. The higher and heavier the object, the more gravitational energy is stored. When a person rides a bicycle down a steep hill and picks up speed, the gravitational energy is converting to motion energy. Hydropower is another example of gravitational energy, where gravity forces water down through a hydroelectric turbine to produce electricity.
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Kinetic energy
Kinetic energy is the motion of waves, electrons, atoms, molecules, substances, and objects.
Electrical energy is delivered by tiny, charged particles, called electrons, that typically move through a wire. Lightning is an example of electrical energy in nature.
Thermal energy, or heat, is the energy that comes from the movement of atoms and molecules in a substance. Heat increases when these particles move faster. Geothermal energy is the thermal energy in the earth.
Radiant energy is electromagnetic energy that travels in transverse waves. Radiant energy includes visible light, x-rays, gamma rays, and radio waves. Light is one type of radiant energy. Sunshine is radiant energy, which provides the fuel and warmth that make life on earth possible.
Motion energy is energy stored in moving objects. The faster an object moves, the more energy is stored. It takes energy to get an object moving, and energy is released when an object slows down. Wind is an example of motion energy. A dramatic example of motion energy is a car crash—a car comes to a total stop and releases all of its motion energy at once in an uncontrolled instant.
Sound is energy moving through substances in longitudinal (compression or rarefaction) waves. Sound is produced when a force causes an object or substance to vibrate. The energy is transferred through the substance in a wave. Typically, the energy in sound is lower than in other forms of energy.
| Content source |
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| EIA |
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Deep dive
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Fossil solar energy
Oil, natural gas, and coal are derivatives of solar energy. They were formed from the remains of living things in the geological past, all supported by photosynthesis. However, the rate at which we currently use these resources is far from being matched by the rate at which photosynthesis creates new organic fuels.
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44 QW of low entropy energy recieved from our Sun
The Sun is the major source of energy for Earth's oceans, atmosphere, land, and biosphere. The solar radiation that reaches the Earth has a significant amount of energy.
- At full intensity, the solar power to the Earth at the surface of the upper atmosphere is about 1367 W/m2
- Approximately 342 watts of solar energy is falling upon every square meter of Earth (Taken into account the fact that only half of the Earth faces the Sun, as well as accounting for the different amounts of sunlight that hit different latitudes and the amount of atmosphere the sunlight has to pass through)
This is globally a tremendous amount of energy — 44 quadrillion watts of power to be exact.
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In the American system each of the denominations above 1,000 millions (the American billion) is 1,000 times the preceding one
- one trillion = 1,000 billions
- one quadrillion = 1,000 trillions
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Physical and biological processes on Earth are the result of energy flow through the Earth system. Following the law of conservation of energy, (the first law of thermodynamics and the second law of thermodynamics - see core ideas: entropy), there will always be a 'loss' of usable energy starting from the fotons from the sun (energy at the lowest entropy).
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Renewable energies such as wind and solar power originate from the Sun. (Biomass and fossil fuels are simply solar energy stored in a secondary form with higher entropy). These can, (together with nuclear), be converted into other energy forms such as electricity and heat that are more useful to us (and have a lower entropy than fossil energy).
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| Content source |
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| Canadian Energy Education - University of Calgary |
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40 TW of low entropy energy needed (as a Type 1 civilization)
| The drive behind the development of renewable energies and the deeper philosophy of harnessing the energy of the planet - Stoffel Fourie - Academia letters Art. 2816 - 2021 |
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| Moving earth from a Type 0 to a Type 1 civilization*: what will be the factors influencing our energy strategies?* A Type I civilization, with a technological level to which earth is moving towards to, with an estimated energy consumption of 40 TW, meaning a civilization manipulating the energy resources of its home planet (Ćirković, 2015).
. The technological advancement of the planet drives the need for energy (Jin et al., 2018). The bilateral relationship between technological innovation and energy consumption shows that technological innovation leads to an increase in energy consumption in the short term, while energy consumption has no significant effect on technological innovation. In the long term, energy consumption is positively and bilaterally related to technological innovation (Jin et al., 2018). Although technological innovation does not directly lead to a reduction in energy consumption, it could benefit sustainability through improving energy efficiency and developing energy structure for countries (Jin et al., 2018). As an example, electronic plasma and LED displays can use between 200W to 800W, depending on their size. The old CRT tube displays used between 30W to 60W, depending on their size. Technological advancement produces better quality equipment, but it is more power hungry and will require more energy to be generated. Global total installed generation capacity is forecast to increase to 10.53 TW by 2030 at a 3.9% Compound annual growth rate (CAGR) by the Global Power Generation Forecasts 2020-2030 in 2021. The future use of electric vehicles will place a heavy demand on generation capacity. Currently electricity grids do not have the capacity to charge millions of electric vehicles but will in time need to expand capacity to support the growing number of these vehicles. Charging infrastructure is an important entity of a power grid. Availability of this infrastructure is a key factor in general acceptance of electric vehicles. In addition to the physical charging facilities, the power grid and energy suppliers must be in place (Salah and Kama, 2016). Vehicle charging units range between 3.7kW for small cars and 22kW for a three phase unit. To reduce charging times at motorway service points, chargers as high as 500kW are being considered which will place much higher loads on the electricity grid. Greater use of electric heating of homes and more electric passenger train transport will also be utilised for medium distances, instead of flying, especially in Europe. All these factors result in a much higher need for energy generation capacity from renewable and environmentally friendly sources. .Earth will become a Type 1 civilization: what energy systems need to be in place? In order for earth to become a Type I civilization we would have to harness all the available energy of our planet at the highest efficiency possible, preferably excluding burning coal, gas and fuel to protect our environment. Therefore, we need to deploy every other available form of energy production, which includes:
In order for earth to make a successful transition from a Type 0 to a Type I civilization and harvest all the energy from the planet, it must not just be a reaction to existential factors (which seems to be currently the case), but it must be part of a larger philosophy or master plan. In 2018 there were about 30 000 power plants worldwide of every type in 164 countries (Byers, et al., 2019). As of 2019, there are an estimated 2,425 coal-fired power plants in the world, with an operating capacity of about 2,000 GW (Jeff Desjardins, Visual Capitalist, 2019). If Kardashev correctly estimated the global energy such a Type I civilization will need, earth only produced 18.75% in 2019 of what is predicted to be needed in terms of electrical energy. Climatic and environmental aspects dictate that carbon based power generation is just not an option to produce the 5 times more energy that is needed to become a Type I civilization. Michio Kaku estimated that it will take earth another 100-plus years to evolve to a Type I civilization. There is a chance that earth as a civilization might not reach this goal. Throughout the history of earth, prominent civilizations disappeared due to wars and conflict in many cases. Furthermore, a Type I global civilization will need skilled workers to develop, maintain and service the advanced equipment and technology. It will be a great challenge, economically and politically, for our global society to work together on a 100-plus year plan to execute this philosophy. (1) |
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How can we transform the energy scene towards a lower entropy stage
Four observations:
- A strong reduction in final energy consumption is expected. Final energy consumption is shrinking, which can be explained by targeted energy efficiency and saving efforts on the one hand, and increasing electrification on the other. By electrifying certain applications (such as domestic heating or passenger road transport), significant efficiency gains are achieved and a lot less energy is consumed: an electric car consumes no less than 3 times less than its fossil equivalent.
- Although final energy demand is falling, electricity use is increasing (strongly): it is doubling or even tripling compared to today. More electricity is needed to meet our future transport and heating needs and to help the industry obtain the necessary electrons to embark on the path to decarbonisation.
- Much more renewable energy and storage capacity needs to be installed. There are (of course) differences between the models, but the installation of solar energy and onshore wind must increase. In particular, the number of photovoltaic panels needs to be drastically increased. Of course, such an evolution must go hand in hand with the expansion of much-needed flexibility. This can be done in the form of batteries, demand response, exchange with foreign countries, but also by controllable production units that step in when there is a shortage and switch down when there is a surplus of weather-dependent renewable energy.
- Thermal capacity is and will remain necessary in the electricity system of the future. Whether it concerns power stations running on green hydrogen or biomethane, or perhaps even modular small nuclear reactors, thermal power stations that are controllable and can be switched on when other forms fail, are and will remain a crucial element.
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| Content source |
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| https://energyeducation.ca/encyclopedia/Main_Page |
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Do you want to know more?
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Usefulness of a given energy (the energy frequency)
| A beautiful Question - Frank Wilczek - Penguin Books - 2016 |
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| If the frequency of your driving force is close to the natural frequency of some pattern, that pattern will leap out in powerful response. [...] Anyone who's pumped their legs and straightened their body to build up motion of a swing, [...], knows how important that is. |
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