Energy degradation and power generation
8.1.1. Thermal energy may be completely converted to work in a single process, but that continuous conversion of this energy into work requires a cyclical process and the transfer of some energy from the system.
8.1.2. Degraded energy is the energy that is lost to the environment during the transfer of energy or the conversion of energy.
8.1.3. In this sankey diagram, 40% of the fuel energy is lost to the environment through the exhaust (byproducts of the energy generation), 30% is lost to the use of coolant to keep the engine cool, and 5% of the energy is lost through friction of the engine parts. This leaves 25% of efficiently used fuel energy.
8.1.1. Thermal energy may be completely converted to work in a single process, but that continuous conversion of this energy into work requires a cyclical process and the transfer of some energy from the system.
8.1.2. Degraded energy is the energy that is lost to the environment during the transfer of energy or the conversion of energy.
8.1.3. In this sankey diagram, 40% of the fuel energy is lost to the environment through the exhaust (byproducts of the energy generation), 30% is lost to the use of coolant to keep the engine cool, and 5% of the energy is lost through friction of the engine parts. This leaves 25% of efficiently used fuel energy.
8.1.4. Electrical energy is produced by converting another type of energy into electricity. This energy can come from the sun, wind, waves, coal, or nuclear reactions. A generator takes energy and uses it to power a generator, which spins magnets around in a circle, inducing electrical current.
World energy sources
8.2.1. Some sources of energy that power the modern world are coal, oil and gas, wood and biomass, nuclear reactions, the sun, wind, and waves.
8.2.2. Renewable energy sources are sources of energy that are sustainable and are infinite, like solar energy and wave energy. Non-renewable energy sources are sources of energy that are used once and cannot be used again, like coal and fossil fuels.
8.2.3. The energy density of a fuel is the amount of energy it provides in one kilogram of the material.
8.2.4. A fuel's importance is dictated by its energy density, because a fuel with a higher energy density will be more efficient and effective than one with a lower energy density.
8.2.5. The relative proportions of world use of energy sources vary due to geographic climate and location. Much of the warmer countries rely on coal and solar energy, while colder countries rely on wind, coal, and biomass to power themselves.
8.2.6. Coal was the most widely used energy source in the 1950s, because it has a medium energy density and there was a lot of it back then. It is non-renewable, and has since been replaced with oil and gas. Like coal, oil and gas are non-renewable sources.
Fossil fuel power production
8.3.1. Fossil fuel consumption increased massively during the Industrial Revolution. Previously, coal, oil and gas were being used, so people knew where to go to get them. Power plants were created to mass produce energy from these sources. Geographically speaking, fossil fuels are found in small amounts all over the world. These are some of the easiest energy sources to find.
8.3.2. Below.
World energy sources
8.2.1. Some sources of energy that power the modern world are coal, oil and gas, wood and biomass, nuclear reactions, the sun, wind, and waves.
8.2.2. Renewable energy sources are sources of energy that are sustainable and are infinite, like solar energy and wave energy. Non-renewable energy sources are sources of energy that are used once and cannot be used again, like coal and fossil fuels.
8.2.3. The energy density of a fuel is the amount of energy it provides in one kilogram of the material.
8.2.4. A fuel's importance is dictated by its energy density, because a fuel with a higher energy density will be more efficient and effective than one with a lower energy density.
8.2.5. The relative proportions of world use of energy sources vary due to geographic climate and location. Much of the warmer countries rely on coal and solar energy, while colder countries rely on wind, coal, and biomass to power themselves.
8.2.6. Coal was the most widely used energy source in the 1950s, because it has a medium energy density and there was a lot of it back then. It is non-renewable, and has since been replaced with oil and gas. Like coal, oil and gas are non-renewable sources.
Fossil fuel power production
8.3.1. Fossil fuel consumption increased massively during the Industrial Revolution. Previously, coal, oil and gas were being used, so people knew where to go to get them. Power plants were created to mass produce energy from these sources. Geographically speaking, fossil fuels are found in small amounts all over the world. These are some of the easiest energy sources to find.
8.3.2. Below.
8.3.3. Oil - Whether oil is transported from production sites to the refineries by maritime or terrestrial routes, the main issues are those of safety, security and respect for the environment. Coal – There are several methods for moving prepared coal from the mine to the markets such as railroads, trucks, barges, and conveyers. Natural Gas - Once natural gas has been extracted from the ground, it is usually transported by pipeline to a refinery, where it is processed. After processing, the natural gas is transported through pipelines to communities and other markets.
8.3.4. Coal and oil both have energy efficiencies of 37%, while natural gas has an efficiency of 45%, slightly higher.
8.3.5. When coal is extracted from the ground, some of the coal is lost to the environment, polluting oceans and releasing greenhouse gases into the air. When it is converted into energy, more greenhouse gases are produced, and the coal is also rendered useless after burning. The same goes for oil and gas. Recovering the natural gas that are dissolved under the saline water is a great concern. For the gas recovered, large amount of salt water needs to be separated from the gas. However, it is very complicated and difficult to seperate the saline water and pollutants from the pure natural gas with the recent technology. The process of natural gas recovery costs a lot.
8.3.4. Coal and oil both have energy efficiencies of 37%, while natural gas has an efficiency of 45%, slightly higher.
8.3.5. When coal is extracted from the ground, some of the coal is lost to the environment, polluting oceans and releasing greenhouse gases into the air. When it is converted into energy, more greenhouse gases are produced, and the coal is also rendered useless after burning. The same goes for oil and gas. Recovering the natural gas that are dissolved under the saline water is a great concern. For the gas recovered, large amount of salt water needs to be separated from the gas. However, it is very complicated and difficult to seperate the saline water and pollutants from the pure natural gas with the recent technology. The process of natural gas recovery costs a lot.