{"id":16542,"date":"2018-01-15T11:53:36","date_gmt":"2018-01-15T11:53:36","guid":{"rendered":"http:\/\/sitepourvtc.com\/?page_id=16542"},"modified":"2022-11-06T11:29:47","modified_gmt":"2022-11-06T11:29:47","slug":"what-is-energy-physics","status":"publish","type":"page","link":"https:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/","title":{"rendered":"What is Energy &#8211; Physics"},"content":{"rendered":"<div   id="8n9s8rpp6h"    class=\"sue-shadow-wrap sue-content-wrap sue-shadow-inline-no\"><div   id="8n9s8rpp6h"    class=\"sue-shadow sue-shadow-style-vertical\">\n<div   id="8n9s8rpp6h"    class=\"sue-panel\" data-url=\"\" data-target=\"self\" style=\"background-color:#ffffff;color:#333333;border-radius:0px;-moz-border-radius:0px;-webkit-border-radius:0px;box-shadow:none;-moz-box-shadow:none;-webkit-box-shadow:none;border:1px solid #cccccc\"><div   id="8n9s8rpp6h"    class=\"sue-panel-content sue-content-wrap\" style=\"padding:15px;text-align:left\">\n<div class=\"su-heading su-heading-style-modern-1-dark su-heading-align-left\" id=\"\" style=\"font-size:13px;margin-bottom:20px\"><div   id="8n9s8rpp6h"    class=\"su-heading-inner\">\n<h2>Article Summary &amp; FAQs<\/h2>\n<\/div><\/div>\n<h3>What is energy?<\/h3>\n<p><strong>Energy<\/strong> is a scalar physical quantity. <a href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/\"><strong>Energy<\/strong><\/a> is generally defined as the\u00a0<strong>potential to do work<\/strong>\u00a0<strong>or produce heat<\/strong>. Sometimes it is like the \u201ccurrency\u201d for performing work. You must have the energy to accomplish work. To do 1 kilojoule of work, you must expend 1 kilojoule of energy. The total energy cannot be created or destroyed.<\/p>\n<h3>Key Facts<\/h3>\n<ul>\n<li>One of the most wonderful properties of the Universe is that <strong>energy<\/strong> <strong>can be transformed<\/strong> from one type to another and <strong>transferred<\/strong> from one object to another.<\/li>\n<li>The SI unit for energy is the same as the unit of work \u2013 the<strong> joule (J)<\/strong>.<\/li>\n<li>1 British Thermal Unit (BTU) = 1055 J<\/li>\n<li>One joule in everyday life and science corresponds to approximately the energy required to lift a medium-size apple (100 g) 1 meter vertically from the surface of the Earth.<\/li>\n<li>Energy exists in many forms. Common energy forms include\u00a0<strong>mechanical energy, kinetic energy,<\/strong> or<strong> thermal energy<\/strong>.<\/li>\n<li>A fundamental aspect of the energy concept is that <strong>energy is conserved.\u00a0<\/strong>This principle is known as\u00a0<strong>the first law of thermodynamics<\/strong>.<\/li>\n<li>One of the striking results of\u00a0<strong>Einstein\u2019s theory of relativity<\/strong>\u00a0is that\u00a0<strong><a title=\"Conservation of Mass-Energy \u2013 Mass-Energy Equivalence\" href=\"http:\/\/sitepourvtc.com\/laws-of-conservation\/law-of-conservation-of-energy\/conservation-of-mass-energy-mass-energy-equivalence\/\">mass and energy are equivalent<\/a>\u00a0and convertible<\/strong>, one into the other.<\/li>\n<li>The IEA estimates that, in 2013, the total primary energy supply (TPES) was 157.5<span class=\"nowrap\">\u00a0<\/span>petawatt hours\u00a0or 1.575\u00d710<sup>17<\/sup>\u00a0Wh\u00a0(157.5\u00a0thousand\u00a0TWh; 5.67\u00d710<sup>20<\/sup> J; 13.54\u00a0billion\u00a0toes).<\/li>\n<\/ul>\n<div   id="8n9s8rpp6h"    class=\"su-divider su-divider-style-dotted\" style=\"margin:10px 0;border-width:2px;border-color:#999999\"><\/div>\n<div   id="8n9s8rpp6h"    class=\"su-accordion su-u-trim\">\n<div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-modern-light su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>What are primary energy sources?<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<strong>What are primary energy sources?<\/strong><\/p>\n<p><strong>Primary energy (PE)<\/strong> is an energy resource found in nature that has not been subjected to any conversion or transformation process. It is the energy contained in\u00a0<strong>raw fuels<\/strong> and other forms of energy received as input to a system. Primary energy sources take many forms, including nuclear energy, fossil energy \u2014 like oil, coal, and natural gas \u2014 and renewable sources like wind, solar, geothermal, and hydropower.<\/p>\n<\/div><\/div>\n<div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-modern-light su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>What is thermodynamics used for?<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<strong>What is thermodynamics used for?<\/strong><\/p>\n<p>Despite the fact it is a\u00a0<strong>very broad subject<\/strong> that affects most fields of science, including biology and microelectronics, we will concern mostly with large-scale observations. Knowledge of <strong>thermodynamics\u00a0<\/strong>is essential to <strong>engineers<\/strong>\u00a0who deal with power plants. Our goal here will be to introduce\u00a0<strong>thermodynamics as the energy conversion science and<\/strong>\u00a0introduce some of the fundamental concepts and definitions used in the study of <strong>engineering thermodynamics<\/strong>. These fundamental concepts and definitions will be further applied to energy systems and finally to\u00a0<strong>thermal<\/strong>\u00a0or\u00a0<strong>nuclear power plants<\/strong>.<\/p>\n<\/div><\/div>\n<div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-modern-light su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>What is nuclear energy?<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>What is nuclear energy?<\/strong><\/p>\n<p><strong>Nuclear energy<\/strong> comes either from spontaneous nuclei conversions or induced nuclei conversions. It is associated with nuclear binding energy. If nuclear energy is generated (splitting atoms, nuclear fission), a small amount of mass (saved in the nuclear binding energy) transforms into pure energy (such as kinetic energy, thermal energy, or radiant energy).<\/p>\n<\/div><\/div>\n<\/div>\n<\/div><\/div>\n<\/div><\/div>\n<p>The term<strong> <em>energy <\/em><\/strong>is very broad, and it has many definitions. Technically, <strong>energy<\/strong> is a <strong>scalar physical quantity<\/strong> that is associated with the state of one or more objects. Energy is generally defined as the <strong>potential to do work<\/strong> <strong>or produce heat<\/strong>. Sometimes it is like the \u201ccurrency\u201d for performing work. You must have the energy to accomplish work. To do 1 kilojoule of work, you must expend 1 kilojoule of energy. It must be added. This interpretation can be misleading because energy is not necessarily available to do work.<\/p>\n<figure id=\"attachment_240\" aria-describedby=\"caption-attachment-240\" style=\"width: 290px\" class=\"wp-caption alignright\"><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/11\/Sun.jpg\"><img loading=\"lazy\" class=\"size-medium wp-image-240\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/11\/Sun-300x298.jpg\" alt=\"The Sun\" width=\"300\" height=\"298\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/11\/Sun-300x298.jpg 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/11\/Sun-150x150.jpg 150w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/11\/Sun.jpg 510w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-240\" class=\"wp-caption-text\">The Sun generates its energy by nuclear fusion of hydrogen nuclei into helium. At its core, the Sun fuses 620 million metric tons of hydrogen each second.<br \/>Source: hyperphysics.phy-astr.gsu.edu<\/figcaption><\/figure>\n<p>One of the most wonderful properties of the Universe is that <strong>energy<\/strong> <strong>can be transformed<\/strong> from one type to another and <strong>transferred<\/strong> from one object to another. Moreover, when transformed from one type to another and transferred from one object to another, the <strong>total amount of energy is always the same<\/strong>. It is one of the elementary properties of the Universe.<\/p>\n<p>For example, burning gasoline to power cars is an energy conversion process we rely on. The <strong>chemical energy<\/strong> in gasoline is<strong> converted<\/strong> to<strong> thermal energy<\/strong>, then converted to <strong>mechanical energy<\/strong> that makes the car move. The <strong>mechanical energy<\/strong> has been converted to <strong>kinetic energy<\/strong>. When we use the brakes to stop a car, that<strong> kinetic energy<\/strong> is converted by friction back to heat or <strong>thermal energy<\/strong>.<\/p>\n<div   id="8n9s8rpp6h"    class=\"collapsible-container\">\n<h2>Energy Units<\/h2>\n<p><strong>Energy<\/strong> is generally defined as the potential to do work or produce heat. This definition causes the SI unit for energy to be the same as the unit of work \u2013 the<strong> joule (J)<\/strong>. Joule is a derived unit of energy, and it is named in honor of <strong>James Prescott Joule<\/strong> and his experiments on the mechanical equivalent of heat. In more fundamental terms, 1 joule is equal to:<\/p>\n<p><strong>1 J = 1 kg.m<sup>2<\/sup>\/s<sup>2<\/sup><\/strong><\/p>\n<p>Since energy is a fundamental physical quantity used in various branches of physics and engineering, there are many units in physics and engineering. These units are summarized in the following points:<\/p>\n<div   id="8n9s8rpp6h"    class=\"su-accordion su-u-trim\"><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Joule (unit: J)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">Joule (unit: J). Joule is a derived unit of energy. It is equal to the energy transferred to an object when a force of one newton acts on that object in the direction of its motion through a distance of one meter.<\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 joule = 0.239 Calories<\/li>\n<li>1 joule = 9.48 x 10<sup>-4<\/sup> BTU<\/li>\n<li>1 joule = 2.778 x 10<sup>-7<\/sup> kWh<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16545\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-1024x291.png\" alt=\"conversion - joule, calorie, kilowatthour - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/p>\n<p><strong>Examples of Energy of 1 Joule:<\/strong><\/p>\n<p>One joule in everyday life and science corresponds to approximately:<\/p>\n<ul>\n<li>The kinetic energy of an object with mass 1 kg moving at \u221a2 \u2248 1.4 m\/s.<\/li>\n<li>The kinetic energy of a 50 kg object (e.g.,, human) moving very slowly &#8211; approximately 0.72 km\/h.<\/li>\n<li>The energy required to lift a medium-size apple (100 g) 1 meter vertically from the surface of the Earth.<\/li>\n<li>The heat required to raise the temperature of 1 g of <a title=\"Properties of Water\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/materials-nuclear-engineering\/properties-of-water\/\">water<\/a> by 0.24 \u00b0C.<\/li>\n<li>The heat required to evaporate of 0.00044 g of liquid water at 100\u00b0C.<\/li>\n<li>The amount of electricity required to light a 1 watt LED for 1 s.<\/li>\n<li>Is released by approximately <strong>3.1<\/strong><strong>\u22c5<\/strong><strong>10<\/strong><strong><sup>10<\/sup><\/strong><strong> fissions <\/strong>in a nuclear reactor.<\/li>\n<\/ul>\n<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Calorie (unit: cal)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>Calorie (unit: cal)<\/strong>. A calorie is a traditional unit of heat. It is part of the \u00a0<strong>International System of Units<\/strong> (SI). It is defined as the amount of heat that must be absorbed by 1 gram of water to raise its temperature by 1 \u00b0C. Its counterpart in the British Imperial system of units is the BTU, which is defined as the amount of heat required to raise the temperature of one pound of water by one degree <a title=\"Fahrenheit Scale \u2013 Fahrenheit Temperature\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-temperature-physics\/fahrenheit-scale-fahrenheit-temperature\/\">Fahrenheit<\/a>. But we have to distinguish between small calorie and large calorie. The large calorie (unit: Cal) is defined in terms of the kilogram rather than the gram. It is equal to 1000 small calories, and it is, i.e., 1 kilocalorie (unit: kcal).\u00a0 Nutritionists use it to characterize the energy-producing potential in food.<\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 calorie = 4.184 J<\/li>\n<li>1 calorie = 0.00397 BTU<\/li>\n<li>1 calorie = 1.16 x 10<sup>-6<\/sup> kWh<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16545\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-1024x291.png\" alt=\"conversion - joule, calorie, kilowatthour - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>British Thermal Unit (unit: BTU)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>British Thermal Unit (unit: BTU)<\/strong>. \u00a0British Thermal Unit is a traditional unit of heat. It is part of the British Imperial system of units. It is defined as the amount of heat that must be absorbed by 1 pound of water to raise its temperature by 1 \u00b0F at the temperature that water has its greatest density (approximately 39 degrees <a title=\"Fahrenheit Scale \u2013 Fahrenheit Temperature\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-temperature-physics\/fahrenheit-scale-fahrenheit-temperature\/\">Fahrenheit<\/a>). Its counterpart in the <strong>International System of Units<\/strong> (SI) is the calorie, defined as the amount of heat required to raise the temperature of one gram of water by one degree <a title=\"Celsius Scale \u2013 Celsius Temperature\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-temperature-physics\/celsius-scale-celsius-temperature\/\">Celsius<\/a>.<\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 British Thermal Unit (BTU) = 1055 J<\/li>\n<li>1 British Thermal Unit (BTU) = 252 calories<\/li>\n<li>1 British Thermal Unit (BTU) = 0.000293 kWh<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16544\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units-1024x291.png\" alt=\"conversion - BTU, foot-pound - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Foot-pound force (unit: ft.lbf)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>Foot-pound force (unit: ft.lbf)<\/strong>. Foot-pound force is a derived unit of work and energy. It is equal to the energy transferred to an object when a force of one pound-force (lbf) acts on that object in the direction of its motion through a distance of one foot. The corresponding SI unit is the joule. The foot-pound is often used in ballistics, especially in the United States. Typically muzzle energies of bullets are given in foot-pound force.<\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 foot-pound force = 1.356 J<\/li>\n<li>1 foot-pound force = 0.324 cal<\/li>\n<li>1 foot-pound force = 0.00129 BTU<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16544\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units-1024x291.png\" alt=\"conversion - BTU, foot-pound - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-BTU-foot-pound-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Kilowatt-hour (unit: kWh)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>Kilowatt-hour (unit: kWh)<\/strong>. Kilowatt-hour is a derived unit of energy. It is used to measure energy, especially electrical energy in commercial applications. One kilowatt-hour is equal to one kilowatt of power produced or consumed over a period of one hour (kilowatts multiplied by the time in hours). Electric utilities commonly use the kilowatt-hour as a billing unit for energy delivered to consumers. 1kW . h = 1kW . 3600s = 3600kWs = 3600kJ = 3600000J. One kilowatt-hour corresponds to the heat required to evaporate 1.58 kg of liquid water at 100\u00b0C. A radio rated at 100 watts continuously operating for 10 hours uses one kilowatt-hour.<\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 kWh = 3.6 x 10<sup>6<\/sup> J<\/li>\n<li>1 kWh = 8.6 x 10<sup>5<\/sup> cal<\/li>\n<li>1 kWh = 3412 BTU<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16545\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-1024x291.png\" alt=\"conversion - joule, calorie, kilowatthour - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-joule-calorie-kilowatthour-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Megawatt-day (unit: MWd)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>Megawatt-day (unit: MWd)<\/strong>. \u00a0Megawatt-day is a derived unit of energy. It is used to measure the energy produced, especially in <strong>power engineering<\/strong>. One megawatt-day is equal to one megawatt of power produced by a power plant over a period of one day (megawatts multiplied by the time in days). <strong>1 MWd = 24,000 kWh<\/strong>. At nuclear power plants, there are also gigawatt-days because it approximately corresponds to energy produced by power plant over a period of one day. This unit (MWd) was also used to derive the unit of <strong>fuel burnup<\/strong>. The most commonly used measure of fuel burnup is the <a title=\"Energy Release from Fission\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/fission\/energy-release-from-fission\/\">fission energy release<\/a> per unit mass of fuel. Therefore fuel burnup of <a title=\"Nuclear Fuel\" href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/nuclear-fuel\/\">nuclear fuel<\/a> normally has units of megawatt-days per metric tonne (<strong>MWd\/MTU<\/strong>), where tonne refers to a metric ton of uranium metal (sometimes MWd\/tU HM as Heavy Metal). In this field, the megawatt-day refers to the reactor\u2019s thermal power, not the fraction converted to electricity. For example, for a typical nuclear reactor with thermal power of <strong>3000 MWth<\/strong>, about <strong>~1000MWe<\/strong> of electrical power is generated in the generator. For example, a reactor with 100 000 kg of fuel operating at 3000MWth power level for 1000 days would have a burnup increase of 30,000 MWd\/MTU. In words of fissions, the fissioning of about 1 g of <a title=\"Uranium 235\" href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/nuclear-fuel\/uranium\/uranium-235\/\">U-235<\/a> produces about 1 MWd of thermal energy (see: <a title=\"Energy Release from Fission\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/fission\/energy-release-from-fission\/\">Energy Release per Fission<\/a>).<\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 MWd = 8.64 x 10<sup>10<\/sup> J<\/li>\n<li>1 MWd = 2.06 x 10<sup>10<\/sup> cal<\/li>\n<li>1 MWd = 8.19 x 10<sup>7<\/sup> BTU<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16546\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units-1024x291.png\" alt=\"conversion -megawattday, electronvolt - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Electronvolt (unit: eV)<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<figure id=\"attachment_16549\" aria-describedby=\"caption-attachment-16549\" style=\"width: 178px\" class=\"wp-caption alignright\"><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/electronvolt-definition-min.png\"><img loading=\"lazy\" class=\"size-medium wp-image-16549\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/electronvolt-definition-min-188x300.png\" alt=\"Electronvolt - definition\" width=\"188\" height=\"300\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/electronvolt-definition-min-188x300.png 188w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/electronvolt-definition-min.png 500w\" sizes=\"(max-width: 188px) 100vw, 188px\" \/><\/a><figcaption id=\"caption-attachment-16549\" class=\"wp-caption-text\">Electronvolt is equal to energy gained by a single electron when it is accelerated through 1 volt of electric potential difference. The work done on the charge is given by the charge times the voltage difference, therefore the work W on electron is: W = qV = (1.6 x 10-19 C) x (1 J\/C) = 1.6 x 10-19 J.<\/figcaption><\/figure>\n<p><strong>Electronvolt (unit: eV)<\/strong>. Electronvolts are a traditional unit of energy, particularly in <a title=\"Atomic and Nuclear Physics\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/\">atomic and nuclear physics<\/a>. An electronvolt is equal to the energy gained by a single electron when <strong>accelerated<\/strong> through <strong>1 volt<\/strong> of <strong>electric potential<\/strong> difference. The work done on the charge is given by the charge times the voltage difference, therefore the work W on electron is: W = qV = (1.6 x 10<sup>-19 <\/sup>C) x (1 J\/C) = <strong>1.6 x 10<sup>-19<\/sup> J<\/strong>. Since this is a very small unit, it is more convenient to use multiples of electronvolts: kilo-electronvolts (keV), mega-electronvolts (MeV), giga-electronvolts (GeV), and so on. Since Albert Einstein showed that <a title=\"Conservation of Mass-Energy \u2013 Mass-Energy Equivalence\" href=\"http:\/\/sitepourvtc.com\/laws-of-conservation\/law-of-conservation-of-energy\/conservation-of-mass-energy-mass-energy-equivalence\/\">mass and energy<\/a> are <strong>equivalent and convertible<\/strong> one into the other, the electronvolt is also a unit of mass. It is common in particle physics, where units of mass and energy are often interchanged, to express mass in units of eV\/c<sup>2<\/sup>, where c is the speed of light in a vacuum (from E = mc<sup>2<\/sup>). For example, it can be said the <strong>proton<\/strong> has a mass of <strong>938.3 MeV<\/strong>, although strictly speaking, it should be <strong>938.3 MeV\/c<sup>2<\/sup><\/strong>. For another example, an <a title=\"Positron Annihilation\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/beta-particle\/positron-annihilation-2\/\">electron-positron annihilation<\/a> occurs when a negatively charged electron and a positively charged positron (each with a mass of 0.511 MeV\/c<sup>2<\/sup>) collide. When an electron and a positron collide, they annihilate, resulting in the complete conversion of their rest mass to pure energy (according to the <a title=\"E=mc2 Meaning\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/nuclear-energy\/emc2-meaning\/\">E=mc<sup>2<\/sup> formula<\/a>) in the form of two oppositely directed 0.511 MeV <a title=\"Gamma Rays \/ Gamma Radiation\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/photon\/gamma-ray\/\">gamma rays<\/a> (photons).<\/p>\n<p style=\"text-align: center;\"><strong>e<\/strong><strong><sup>\u2212<\/sup><\/strong><strong> + e<\/strong><strong><sup>+<\/sup><\/strong><strong> \u2192 \u03b3 + \u03b3 (2x 0.511 MeV)<\/strong><\/p>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li>1 eV = 1.603 x 10<sup>-19<\/sup> J<\/li>\n<li>1 eV = 3.83 x 10<sup>-20<\/sup> cal<\/li>\n<li>1 eV = 1.52 x 10<sup>-22<\/sup> BTU<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-16546\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units-1024x291.png\" alt=\"conversion -megawattday, electronvolt - energy units\" width=\"669\" height=\"190\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units-1024x291.png 1024w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units-300x85.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/01\/conversion-megawattday-electronvolt-energy-units.png 1308w\" sizes=\"(max-width: 669px) 100vw, 669px\" \/><\/a><\/p>\n<h3>Example of Energies in Electronvolts<\/h3>\n<ul>\n<li><a title=\"Thermal Neutron\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/neutron\/thermal-neutron\/\"><strong>Thermal neutrons<\/strong><\/a> are neutrons in thermal equilibrium <strong>with a surrounding medium of the temperature of 290K (17 \u00b0C or 62 \u00b0F)<\/strong>. Most probable energy at 17\u00b0C (62\u00b0F) for Maxwellian distribution is <strong>0.025 eV<\/strong> (~2 km\/s).<\/li>\n<li>The thermal energy of a molecule is at room temperature, about <strong>0.04 eV<\/strong>.<\/li>\n<li>Approximately <strong>1 eV<\/strong> corresponds to an <strong>infrared <a title=\"Photon \u2013 Fundamental Particle\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/photon\/\">photon<\/a><\/strong> of wavelength 1240 nm.<\/li>\n<li>Visible light photons have energies in range 1.65 eV (red) &#8211; 3.26 eV (violet).<\/li>\n<li>The first <a title=\"What is Nuclear Resonance \u2013 Compound Nucleus\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/nuclear-engineering-fundamentals\/neutron-nuclear-reactions\/compound-nucleus-reactions\/what-is-nuclear-resonance-compound-nucleus\/\">resonance<\/a> in n + <a href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/nuclear-fuel\/uranium\/uranium-238\/\"><sup>238<\/sup>U<\/a> reaction is <strong>at 6.67 eV <\/strong>(energy of incident neutron), which corresponds to the first <strong>virtual level in <\/strong><strong><sup>239<\/sup><\/strong><strong>U<\/strong>, which has a total width of only 0.027 eV mean life of this state is 2.4\u00d710<sup>-14<\/sup>s.<\/li>\n<li>The ionization energy of atomic hydrogen is <strong>13.6 eV<\/strong>.<\/li>\n<li>Carbon-14 decays into nitrogen-14 through <a href=\"http:\/\/www.personal-dosimeter.com\/ionizing-radiation\/beta-decay\/\">beta decay<\/a> (pure beta decay). The emitted <a title=\"Beta Particle\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/beta-particle\/\">beta particles<\/a> have a maximum energy of 156 keV, while their weighted mean energy is <strong>49 keV<\/strong>.<\/li>\n<li>High energy diagnostic medical x-ray photons have kinetic energies of about <strong>200 keV.<\/strong><\/li>\n<li><strong>Thallium 208<\/strong>, one of the\u00a0nuclides in the <a title=\"Uranium 232\" href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/nuclear-fuel\/uranium\/uranium-232\/\"><strong><sup>232<\/sup>U<\/strong><\/a> decay chain, <strong>emits <\/strong><strong><a href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/photon\/gamma-ray\/\">gamma rays<\/a><\/strong><strong> of 2.6 MeV, which are very energetic and highly penetrating. <\/strong><\/li>\n<li>The typical kinetic energy of <a title=\"Alpha Particle\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/alpha-particle\/\"><strong>alpha particle<\/strong><\/a> from radioactive decay is about <strong>5 MeV<\/strong>. It is caused by the mechanism of their production.<\/li>\n<li><strong>The <a title=\"Energy Release from Fission\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/fission\/energy-release-from-fission\/\">total energy released<\/a><\/strong> in a reactor is <strong>about 210 MeV<\/strong> per <a href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/nuclear-fuel\/uranium\/uranium-235\/uranium-235-fission\/\"><sup>235<\/sup>U fission<\/a>, distributed as shown in the table. In a reactor, <strong>the average recoverable energy<\/strong> per fission is <strong>about 200 MeV<\/strong>, being the total energy minus the energy of <a href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/fundamental-particles\/antineutrino\/\">antineutrinos<\/a> that are radiated away.<\/li>\n<li>Cosmic rays can have energies of <strong>1 MeV &#8211; 1000 TeV<\/strong>.<\/li>\n<\/ul>\n<\/div><\/div><\/div>\n<h2>Examples of Energy of 1 Joule<\/h2>\n<p><strong>One joule<\/strong> in everyday life and science corresponds to approximately:<\/p>\n<ul>\n<li>The kinetic energy of an object with mass <strong>1 kg<\/strong> moving at \u221a2 \u2248 <strong>1.4 m\/s<\/strong>.<\/li>\n<li>The kinetic energy of a <strong>50 kg<\/strong> object (e.g.,, human) moving very slowly &#8211; approximately <strong>0.72 km\/h<\/strong>.<\/li>\n<li>The energy required to lift a medium-size apple (<strong>100 g<\/strong>) <strong>1 meter vertically<\/strong> from the surface of the Earth.<\/li>\n<li>The heat required to raise the temperature of <strong>1 g of <a title=\"Properties of Water\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/materials-nuclear-engineering\/properties-of-water\/\">water<\/a> by 0.24 \u00b0C<\/strong>.<\/li>\n<li>The heat required to <strong>evaporate<\/strong> of <strong>0.00044 g of liquid water<\/strong> at 100\u00b0C.<\/li>\n<li>The amount of electricity required to light a <strong>1 watt LED<\/strong> for <strong>1 s<\/strong>.<\/li>\n<li>Is released by approximately <strong>3.1<\/strong><strong>\u22c5<\/strong><strong>10<\/strong><strong><sup>10<\/sup><\/strong><strong> fissions <\/strong>in a nuclear reactor.<\/li>\n<\/ul>\n<h2>Forms of Energy<\/h2>\n<p>Energy exists in many forms. Common energy forms include <strong>mechanical energy<\/strong> that is classically divided into <strong>kinetic<\/strong> and <strong>potential energy<\/strong>. The kinetic energy is related to the velocity of a <strong>moving object<\/strong>. The potential energy is related to an <strong>object\u2019s position<\/strong> in a <strong>force field<\/strong> (gravitational, electric, or magnetic). Tension in a spring or surface film tension is another form of potential mechanical energy (elastic energy). There are many other forms of energy, including electrical, magnetical, chemical, and <strong>nuclear energy<\/strong>.<\/p>\n<p><strong>In thermodynamics,<\/strong> the concept of energy is broadened to account for other observed changes. Thermodynamics deals with another type of energy called \u201c<strong>thermal energy<\/strong>\u201d or \u201c<strong>internal energy<\/strong>\u201d. The only ways the energy of a closed system can be changed are through the transfer of energy <strong>by work<\/strong> or <strong>by heat<\/strong>. Further, based on the experiments of Joule and others, a fundamental aspect of the energy concept is that <strong>energy is conserved. <\/strong>This principle is known as <strong>the first law of thermodynamics<\/strong>. In general, energy is a fundamental concept of thermodynamics and one of the most significant aspects of engineering analysis.<\/p>\n<div   id="8n9s8rpp6h"    class=\"su-accordion su-u-trim\"><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span> Mechanical energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">In physics, <a title=\"What is Mechanical Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-mechanical-energy\/\"><strong>mechanical energy<\/strong> (E<sub>mech<\/sub>)<\/a> is the energy associated with the <strong>motion<\/strong> and<strong> position<\/strong> of an object, usually in some force field (e.g.,, gravitational field). <strong>Mechanical energy<\/strong> (and thermal energy) can be separated into two categories, transient and stored. Transient energy is energy in motion, that is, energy being transferred from one place to another. Stored energy is the energy contained within a substance or object. Transient mechanical energy is commonly referred to as <strong>work<\/strong>. Stored mechanical energy exists in one of two forms: <strong>kinetic<\/strong> or <strong>potential.<\/strong><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Kinetic energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>The <a title=\"What is Kinetic Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-kinetic-energy\/\">kinetic energy, <em>K<\/em><\/a><\/strong>, is defined as the energy stored in an object because of its motion. An object in motion can do work and thus can be said to have energy. It is called kinetic energy, from the Greek word kinetics, meaning \u201cmotion.\u201d<\/p>\n<p>The <strong>kinetic energy<\/strong> depends on the speed of an object and is the ability of a moving object to do work on other objects when it collides with them. On the other hand, the kinetic energy of an object represents the amount of energy required to increase the velocity of the object from rest (v = 0) to its final velocity. The kinetic energy also depends linearly on the mass, which is a numerical measure of an object\u2019s <strong>inertia <\/strong>and the measure of an object\u2019s resistance to acceleration when a force is applied.<\/p>\n<p>We define the quantity:<\/p>\n<p><em><strong>K = \u00bd mv<sup>2<\/sup><\/strong><\/em><\/p>\n<p>to be the <strong>translational kinetic energy<\/strong> of the object. It must be added, and it is called the \u201ctranslational\u201d kinetic energy to distinguish it from rotational kinetic energy<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Potential energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><a title=\"What is Potential Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-potential-energy\/\"><strong>Potential energy<\/strong><\/a>, U, is defined as the <strong>energy stored<\/strong> in an object subjected to a conservative force. Common types include the <strong>gravitational potential energy<\/strong>, the <strong>elastic potential energy<\/strong> of an extended spring, and the <strong>electric potential energy<\/strong> of an electric charge in an electric field, and so on.<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Gravitational energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<p style=\"text-align: left;\" align=\"center\">In classical mechanics, the <a title=\"Gravitational Potential Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-potential-energy\/gravitational-potential-energy\/\">gravitational potential energy<\/a> (U) is the energy an object possesses because of its position in a gravitational field. Gravitational potential (V; the gravitational energy per unit mass) at a location is equal to the work (energy transferred) per unit mass that would be needed to move the object from a fixed reference location to the location of the object. The most common use of gravitational potential energy is for an object near the surface of the Earth, where the gravitational acceleration can be assumed to be constant at about 9.8 m\/s<sup>2<\/sup>.<\/p>\n<p align=\"center\"><strong>U =\u00a0mgh<\/strong><\/p>\n<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Internal energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">In thermodynamics,<a title=\"Internal Energy \u2013 Thermal Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/internal-energy-thermal-energy\/\"><strong> internal energy<\/strong><\/a> (also called <strong>thermal energy<\/strong>) is defined as the energy associated with <strong>microscopic forms of energy<\/strong>. It is an <a title=\"Extensive and Intensive Properties\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/extensive-and-intensive-properties\/\">extensive quantity<\/a>, and it depends on the size of the system or on the amount of substance it contains. The SI unit of<strong> internal energy<\/strong> is the<strong> joule (J)<\/strong>. It is the energy contained within the system, excluding the kinetic energy of motion of the system as a whole and the system\u2019s potential energy. <strong>Microscopic forms of energy<\/strong> include those due to the <strong>rotation<\/strong>, <strong>vibration, translation<\/strong>, and <strong>interactions<\/strong> among the molecules of a substance. None of these forms of energy can be measured or evaluated directly. Still, techniques have been developed to evaluate the change in the total sum of all these microscopic forms of energy.<\/p>\n<p>In addition, energy can be stored in the chemical bonds between the atoms that make up the molecules. This energy storage on the atomic level includes energy associated with electron orbital states, nuclear spin, and binding forces in the nucleus.<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Enthalpy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">In thermodynamics, the <a title=\"What is Enthalpy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-enthalpy\/\"><strong>enthalpy<\/strong><\/a> is a measurement of energy in a thermodynamic system. It is the thermodynamic quantity equivalent to the total heat content of a system. The <strong>enthalpy<\/strong> is defined to be the sum of the internal energy <strong>E<\/strong> plus the product of the pressure <strong>p<\/strong> and volume <strong>V. <\/strong>In many thermodynamic analyses, the sum of the internal energy U and the product of pressure p and volume V appears. Therefore it is convenient to give the combination a name, enthalpy, and a distinct symbol, H.<\/p>\n<p>The enthalpy is the preferred expression of system energy changes in many chemical, biological, and physical measurements <strong>at constant pressure<\/strong>. It is so useful that it is tabulated in the <a title=\"Steam Tables \u2013 Specific Properties of Water and Steam\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/steam-tables\/\"><strong>steam tables<\/strong><\/a> along with <a title=\"What is Specific Volume\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-specific-volume\/\">specific volume<\/a> and <a title=\"Specific Internal Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/internal-energy-thermal-energy\/specific-internal-energy\/\">specific internal energy<\/a>. It is due to the fact. It <strong>simplifies the description of energy transfer<\/strong>. At constant pressure, the enthalpy change equals the energy transferred from the environment through heating <strong>(Q = H<sub>2<\/sub> \u2013 H<sub>1<\/sub>)<\/strong> or work other than expansion work. For a variable-pressure process, the difference in enthalpy is not quite as obvious.<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Entropy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">In thermodynamics and statistical physics, <a title=\"What is Entropy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-entropy\/\"><strong>entropy<\/strong><\/a> is a quantitative measure of disorder or the energy in a system to do work.<\/p>\n<p>In statistical physics, entropy is a measure of the disorder of a system. What disorder refers to is the <strong>number of microscopic configurations<\/strong>, <strong>W<\/strong>, that a thermodynamic system can have when in a state as specified by certain macroscopic variables (<a title=\"What is Volume \u2013 Physics\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-volume-physics\/\">volume<\/a>, <a title=\"What is Energy \u2013 Physics\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/\">energy<\/a>, <a title=\"What is Pressure \u2013 Physics\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-pressure-physics\/\">pressure<\/a>, and <a title=\"What is Temperature \u2013 Physics\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/thermodynamic-properties\/what-is-temperature-physics\/\">temperature<\/a>). By \u201cmicroscopic states\u201d, we mean the exact states of all the molecules making up the system.<\/p>\n<p>Mathematically, the exact definition is:<\/p>\n<p><strong>Entropy = (Boltzmann\u2019s constant k) x logarithm of the number of possible states<\/strong><\/p>\n<p><em><strong>S = k<sub>B<\/sub> logW<\/strong><\/em><\/p>\n<p>This equation, which relates the microscopic details, or microstates, of the system (via <em>W<\/em>) to its macroscopic state (via the <strong>entropy <em>S<\/em><\/strong>), is the key idea of statistical mechanics. In a closed system, entropy never decreases, so in the Universe, entropy is irreversibly increasing. In an open system (for example, a growing tree), entropy can decrease, and the order can increase, but only at the expense of increasing entropy somewhere else (e.g.,, in the Sun).<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span> Gibbs Free Energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">In thermodynamics, the <a title=\"Gibbs Free Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/gibbs-free-energy\/\"><strong>Gibbs free energy<\/strong><\/a> is a thermodynamic potential that is defined as the <a title=\"What is Enthalpy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-enthalpy\/\">enthalpy<\/a> of the system minus the product of the temperature times the <a title=\"What is Entropy\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/what-is-entropy\/\">entropy<\/a> of the system. Since the <strong>enthalpy<\/strong> is defined to be the sum of the internal energy <strong>E<\/strong> plus the product of the pressure <strong>p<\/strong> and volume <strong>V.<\/strong><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Electrical Energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">Electrical energy is the energy derived from electric potential energy or kinetic energy. A typical <a href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/\"><strong>nuclear power plant<\/strong><\/a> has an electric-generating capacity of <strong>1000 MWe<\/strong>. It produces 1 000 000 000 joules of electrical energy per second. The heat source in the nuclear power plant is a <a href=\"http:\/\/sitepourvtc.com\/nuclear-power-plant\/what-is-nuclear-reactor\/\"><strong>nuclear reactor<\/strong><\/a>. As is typical in all conventional thermal power stations, the heat is used to generate steam which drives a <strong>steam turbine<\/strong> connected to a generator that produces electricity. The turbines are heat engines subject to the efficiency limitations imposed by the <strong>second law of thermodynamics<\/strong>. In modern nuclear power plants, the overall thermodynamic efficiency is about <strong>one-third <\/strong>(33%), so <strong>3000 MWth<\/strong> of thermal power from the fission reaction is needed to generate <strong>1000 MWe<\/strong> of electrical power.<\/p>\n<p>Since <strong>voltage<\/strong> is <strong>electric potential energy<\/strong> per unit charge, <strong>Kirchhoff\u2019s voltage law<\/strong> can be seen to be a consequence of the <strong>conservation of electrical energy<\/strong>. <strong>Kirchhoff\u2019s voltage law states:<\/strong><\/p>\n<p><em>The algebraic sum of the voltages (drops or rises) encountered in traversing any loop of a circuit in a specified direction must be zero.<\/em><\/p>\n<p>The algebraic sum of the voltages (drops or rises) encountered in traversing any loop of a circuit in a specified direction must be zero.<\/p>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/kirchhoffs-voltage-law-equation1.png\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-15733\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/kirchhoffs-voltage-law-equation1.png\" alt=\"kirchhoffs-voltage-law-equation1\" width=\"89\" height=\"58\" \/><\/a><\/p>\n<p>Simply, the voltage changes around any closed loop must sum to zero. The sum of the <strong>voltage rises<\/strong> is equal to the sum of the<strong> voltage drops<\/strong> in a loop. No matter what path you take through an electric circuit, if you return to your starting point, you must measure the same voltage, constraining the net change around the loop to be zero. This rule is equivalent to saying that each point on a mountain has only one elevation above sea level. If you start from any point and return to it after walking around the mountain, the algebraic sum of the elevation changes that you encounter must be zero.<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Radiant Energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\">In physics, <strong>radiant energy<\/strong> is the energy of <strong>electromagnetic<\/strong> and <strong>gravitational radiation<\/strong>. The term \u201c<strong>radiant energy<\/strong>\u201d is most commonly used in the fields of radiometry, solar energy, heating, and lighting. As energy, its SI unit is the <strong>joule (J)<\/strong>. The quantity of radiant energy may be calculated by integrating radiant flux concerning time. <strong>Radiant heat transfer<\/strong> is very important in the power industry because it is one of the most important ways to transfer thermal energy. It does not need a medium, such as air or metal, to take place. Any material that has a temperature above absolute zero gives off some radiant energy. Most energy of this type is in the infra-red region of the electromagnetic spectrum, although some of it is in the visible region.<\/p>\n<p><strong>The radiant heat transfer<\/strong> rate from a body (e.g.,, a black body) to its surroundings is proportional to the <strong>fourth power<\/strong> of the absolute temperature. It can be expressed by the following equation:<\/p>\n<p><strong><em><span style=\"font-size: 30px;\">q = \u00a0\u03b5\u03c3T<sup>4<\/sup><\/span><\/em><\/strong><\/p>\n<p>where<strong> \u03c3<\/strong> is a fundamental physical constant called the <strong>Stefan\u2013Boltzmann constant<\/strong>, which is equal to<strong> 5.6697&#215;10<sup>-8<\/sup> W\/m<sup>2<\/sup>K<sup>4<\/sup><\/strong>, this relationship is called the <strong>Stefan\u2013Boltzmann law<\/strong>. The <strong>emissivity, \u03b5<\/strong>, of the surface of a material is its effectiveness in emitting energy as thermal radiation and varies between 0.0 and 1.0. By definition, a black body in thermal equilibrium has an emissivity of <em>\u03b5<\/em> = 1.0. It can be seen and radiation heat transfer is important at very high temperatures and in a vacuum.<\/p>\n<p>Two bodies that radiate toward each other have a net heat flux between them. The net flow rate of heat between them is given by:<\/p>\n<p><em><strong>Q = \u03b5\u03c3A<sub>1-2<\/sub>(T<sup>4<\/sup><sub>1<\/sub> \u2212T<sup>4<\/sup><sub>2<\/sub>) \u00a0[J\/s]<\/strong><\/em><\/p>\n<p><em><strong>q = \u00a0\u03b5\u03c3(T<sup>4<\/sup><sub>1<\/sub> \u2212T<sup>4<\/sup><sub>2<\/sub>) [J\/m<sup>2<\/sup>s]<\/strong><\/em><\/p>\n<p>The area factor A<sub>1-2<\/sub> is the area viewed by body 2 of body 1 and can become fairly difficult to calculate.<\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Ionization Energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>Ionization energy<\/strong>, also called<strong> ionization potential<\/strong>, is the energy necessary to<strong> remove an electron<\/strong> from the neutral atom.<\/p>\n<p>X + energy \u2192 X<sup>+<\/sup> + e<sup>\u2212<\/sup><\/p>\n<p>where X is any atom or molecule capable of ionizing, X<sup>+<\/sup> is that atom or molecule with an electron removed (positive ion), and e<sup>\u2212<\/sup> is the removed electron.<\/p>\n<p>There is ionization energy for each successive electron removed. The electrons that circle the nucleus move in fairly well-defined orbits. Some of these electrons are more tightly bound in the atom than others. For example, only 7.38 eV is required to remove the outermost electron from a lead atom, while 88,000 eV is required to remove the innermost electron.<\/p>\n<ul>\n<li><strong>Ionization energy<\/strong> is lowest for the alkali metals, which have a single electron outside a closed shell.<\/li>\n<li><strong>Ionization energy<\/strong> increases across a row on the periodic maximum for the noble gases which have closed shells.<\/li>\n<\/ul>\n<p>For example, sodium requires only 496 kJ\/mol or 5.14 eV\/atom to ionize it. On the other hand, neon, the noble gas, immediately preceding it in the periodic table, requires 2081 kJ\/mol or 21.56 eV\/atom.<\/p>\n<p>The ionization energy associated with the removal of the first electron is most commonly used. The <em>n<\/em>th ionization energy refers to the energy required to remove an electron from the species with a charge of (<em>n<\/em>-1).<\/p>\n<p>1st ionization energy<\/p>\n<p>X \u2192 X<sup>+<\/sup> + e<sup>\u2212<\/sup><\/p>\n<p>2nd ionization energy<\/p>\n<p>X<sup>+<\/sup> \u2192 X<sup>2+<\/sup> + e<sup>\u2212<\/sup><\/p>\n<p>3rd ionization energy<\/p>\n<p>X<sup>2+<\/sup> \u2192 X<sup>3+<\/sup> + e<sup>\u2212<\/sup><\/p>\n<p>For example, only 7.38 eV is required to remove the outermost electron from a lead atom, while 88,000 eV is required to remove the innermost electron.<\/p>\n<figure id=\"attachment_16766\" aria-describedby=\"caption-attachment-16766\" style=\"width: 1129px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Ionization-energy-first-min.png\"><img loading=\"lazy\" class=\"size-full wp-image-16766\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Ionization-energy-first-min.png\" alt=\"Ionization energy\" width=\"1139\" height=\"432\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Ionization-energy-first-min.png 1139w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Ionization-energy-first-min-300x114.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Ionization-energy-first-min-1024x388.png 1024w\" sizes=\"(max-width: 1139px) 100vw, 1139px\" \/><\/a><figcaption id=\"caption-attachment-16766\" class=\"wp-caption-text\">Source: wikipedia.org License: CC BY-SA 3.0<\/figcaption><\/figure>\n<\/div><\/div>\n<div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Nuclear Energy<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><a title=\"Nuclear Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/nuclear-energy\/\"><strong>Nuclear energy<\/strong><\/a> comes either from spontaneous nuclei conversions or induced\u00a0nuclei conversions. Among these conversions (<a title=\"Nuclear Reactions\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/nuclear-reactions\/\">nuclear reactions<\/a>) are <a title=\"Nuclear Fission\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/fission\/\">nuclear fission<\/a>, <a title=\"Radioactive Decay\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/radioactive-decay\/\">nuclear decay<\/a>, and <a title=\"Nuclear Fusion\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/nuclear-fusion\/\">nuclear fusion<\/a>. Conversions are associated <strong>with mass and energy changes<\/strong>. One of the striking results of <strong>Einstein\u2019s theory of relativity<\/strong> is that <strong>mass and energy are equivalent and convertible<\/strong>, one into the other. Equivalence of the mass and energy is described by Einstein\u2019s famous formula:<\/p>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/10\/emc2-e1414305346127.png\"><img loading=\"lazy\" class=\"aligncenter size-large wp-image-45\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/10\/emc2-1024x666.png\" alt=\"E=MC2\" width=\"669\" height=\"435\" \/><\/a><\/div><\/div><\/div>\n<h2>Mass-energy Equivalence<\/h2>\n<p>One of the striking results of <strong>Einstein\u2019s theory of relativity<\/strong> is that <strong><a title=\"Conservation of Mass-Energy \u2013 Mass-Energy Equivalence\" href=\"http:\/\/sitepourvtc.com\/laws-of-conservation\/law-of-conservation-of-energy\/conservation-of-mass-energy-mass-energy-equivalence\/\">mass and energy are equivalent<\/a> and convertible<\/strong>, one into the other. Equivalence of the mass and energy is described by Einstein\u2019s famous formula:<\/p>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/10\/emc2-e1414305346127.png\"><img loading=\"lazy\" class=\"aligncenter size-medium wp-image-45\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2014\/10\/emc2-300x195.png\" alt=\"E=MC2\" width=\"300\" height=\"195\" \/><\/a><\/p>\n<p>where M is the small amount of mass and C is the speed of light.<\/p>\n<p>What does that mean? If nuclear energy is generated (splitting atoms, nuclear fusion), a small amount of mass (saved in the <a title=\"Nuclear Binding Energy\" href=\"http:\/\/sitepourvtc.com\/nuclear-power\/reactor-physics\/atomic-nuclear-physics\/binding-energy\/nuclear-binding-energy\/\"><strong>nuclear binding energy<\/strong><\/a>) transforms into pure energy (such as kinetic energy, thermal energy, or radiant energy).<\/p>\n<p>The energy equivalent of one gram (1\/1000 of a kilogram) of mass is equivalent to:<\/p>\n<ul>\n<li><strong>89.9 terajoules<\/strong><\/li>\n<li><strong>25.0 million kilowatt-hours (\u2248 25 GW\u00b7h)<\/strong><\/li>\n<li><strong>21.5 billion kilocalories (\u2248 21 Tcal)<\/strong><\/li>\n<li><strong>85.2 billion BTUs<\/strong><\/li>\n<\/ul>\n<p>or to the energy released by combustion of the following:<\/p>\n<ul>\n<li><strong>21.5 kilotons of TNT-equivalent energy (\u2248 21 kt)<\/strong><\/li>\n<li><strong>568,000 US gallons of automotive gasoline<\/strong><\/li>\n<\/ul>\n<p>Any time energy is generated, the process can be evaluated from an <strong>E = mc<\/strong><strong><sup>2 <\/sup><\/strong>perspective.<\/p>\n<h2>Principle of Conservation of Energy<\/h2>\n<p>One of the most wonderful properties of the Universe is that <strong>energy can be transformed from one type to another<\/strong> and <strong>transferred from one object to another<\/strong>. Moreover, when transformed from one type to another and transferred from one object to another, the <strong>total amount of energy is always the same<\/strong>. It is one of the elementary properties of the Universe.<\/p>\n<p><strong>In<a title=\"Thermodynamics\" href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/\"> thermodynamics<\/a>,<\/strong> the concept of energy is broadened to account for other observed changes. The <strong>principle of conservation of energy<\/strong> is extended to include a wide variety of ways systems interact with their surroundings. The only ways the energy of a closed system can be changed are through the transfer of energy <strong>by work<\/strong> or <strong>by heat<\/strong>. Further, based on the experiments of Joule and others, a fundamental aspect of the energy concept is that <strong>energy is conserved.\u00a0<\/strong>This principle is known as\u00a0<strong>the first law of thermodynamics<\/strong>. The first law of thermodynamics can be written in various forms:<\/p>\n<p><strong>In words:<\/strong><\/p>\n<p><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/first-law-of-thermodynamics-in-words.png\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-15717\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/first-law-of-thermodynamics-in-words.png\" alt=\"first-law-of-thermodynamics-in-words\" width=\"521\" height=\"105\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/first-law-of-thermodynamics-in-words.png 521w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/first-law-of-thermodynamics-in-words-300x60.png 300w\" sizes=\"(max-width: 521px) 100vw, 521px\" \/><\/a><\/p>\n<figure id=\"attachment_15716\" aria-describedby=\"caption-attachment-15716\" style=\"width: 191px\" class=\"wp-caption alignright\"><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/conservation-of-energy-in-thermodynamics.png\"><img loading=\"lazy\" class=\"wp-image-15716 size-medium\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/conservation-of-energy-in-thermodynamics-201x300.png\" alt=\"conservation-of-energy-in-thermodynamics\" width=\"201\" height=\"300\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/conservation-of-energy-in-thermodynamics-201x300.png 201w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2016\/10\/conservation-of-energy-in-thermodynamics.png 466w\" sizes=\"(max-width: 201px) 100vw, 201px\" \/><\/a><figcaption id=\"caption-attachment-15716\" class=\"wp-caption-text\">The physical layout of the four main devices used in the Rankine cycle and basic energy transfers.<\/figcaption><\/figure>\n<p><strong>Equation form:<\/strong><\/p>\n<p style=\"text-align: center;\"><span style=\"font-size: 20px;\"><strong>\u2206E<\/strong><strong><sub>int<\/sub><\/strong><strong> = Q &#8211; W<\/strong><\/span><\/p>\n<p>where <strong>E<sub>int <\/sub><\/strong>represents the <strong>internal energy<\/strong> of the material, which depends only on the <strong>material\u2019s state<\/strong> (temperature, pressure, and volume),<strong> Q\u00a0<\/strong>is the <strong>net heat added<\/strong> to the system, and <strong>W<\/strong> is the <strong>net work done by<\/strong> the system. We must be careful and consistent in following the sign conventions for Q and W. Because W in the equation is the work done by the system, then if work is done on the system, W will be negative, and E<sub>int<\/sub> will increase.<\/p>\n<p>Similarly, Q is positive for heat added to the system, so if heat leaves the system, Q is negative. This tells us the following: The <strong>internal energy<\/strong> of a system tends to increase if the system absorbs heat or if positive work is done on the system. Conversely, the internal energy tends to decrease if heat is lost by the system or if negative work is done on the system. It must be added Q and W are path-dependent, while E<sub>int<\/sub> is path-independent.<\/p>\n<p><strong>Differential form:<\/strong><\/p>\n<p style=\"text-align: center;\"><span style=\"font-size: 20px;\"><strong>dE<sub>int<\/sub> = dQ \u00a0&#8211; dW<\/strong><\/span><\/p>\n<p>The internal energy E<sub>int<\/sub> of a system tends to increase if energy is added as heat Q and tends to decrease if energy is lost as work W is done by the system.<\/p>\n<h2>Energy Sources<\/h2>\n<figure id=\"attachment_16776\" aria-describedby=\"caption-attachment-16776\" style=\"width: 290px\" class=\"wp-caption alignright\"><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Primary-energy-sources-share-min.png\"><img loading=\"lazy\" class=\"size-medium wp-image-16776\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Primary-energy-sources-share-min-300x261.png\" alt=\"Total Primary Energy Supply\" width=\"300\" height=\"261\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Primary-energy-sources-share-min-300x261.png 300w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/Primary-energy-sources-share-min.png 597w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><figcaption id=\"caption-attachment-16776\" class=\"wp-caption-text\">Total Primary Energy Supply by resource 1993, 2011 and prediction for 2020.<br \/>Source: World Energy Resources &#8211; 2013 Survey<br \/>Used by permission of the World Energy Council<\/figcaption><\/figure>\n<p><strong>Energy sources<\/strong> have always played a very important role in the development of human society. Since the industrial revolution, energy has been a driving force for modern civilization development. Technological development and <strong>consumption of primary energy and<\/strong> the increase of the world population are interdependent. In the past 20 years, the world around us has changed significantly. Technology has become one of the main drivers of economic and social development. The rapid advancement of Information Technology (IT) worldwide has transformed not only the way we think but also the way we act. It must be noted that practically all technologies run on <strong>electrical energy<\/strong>. Therefore,\u00a0the share of electricity is increasing rapidly, faster than <strong>Total Primary Energy Supply<\/strong> (TPES &#8211; \u00a0the sum of production and imports subtracting exports and storage changes.).<\/p>\n<p>At present, fossil fuel is still the world\u2019s predominant energy source. Its extraction, production, and use are not considered efficient regardless of the new technologies available to improve its use and extraction. When studying energy resources, we have to distinguish the <strong>primary energy sources<\/strong> and <strong>secondary energy sources<\/strong>.<\/p>\n<h3>Primary Energy Sources<\/h3>\n<figure id=\"attachment_16775\" aria-describedby=\"caption-attachment-16775\" style=\"width: 427px\" class=\"wp-caption alignright\"><a href=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/primary-energy-sources-table-min.png\"><img loading=\"lazy\" class=\" wp-image-16775\" src=\"http:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/primary-energy-sources-table-min.png\" alt=\"primary energy sources - table\" width=\"437\" height=\"503\" srcset=\"https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/primary-energy-sources-table-min.png 559w, https:\/\/sitepourvtc.com\/wp-content\/uploads\/2017\/02\/primary-energy-sources-table-min-260x300.png 260w\" sizes=\"(max-width: 437px) 100vw, 437px\" \/><\/a><figcaption id=\"caption-attachment-16775\" class=\"wp-caption-text\">Key indicators for 1993, 2011, and prediction for 2020.<br \/>Source: World Energy Resources &#8211; 2013 Survey<br \/>Used by permission of the World Energy Council<\/figcaption><\/figure>\n<p><strong>Primary energy (PE)<\/strong> is an energy resource found in nature that has not been subjected to any conversion or transformation process. It is the energy contained in <strong>raw fuels<\/strong> and other forms of energy received as input to a system. Primary energy sources take many forms, including nuclear energy, fossil energy &#8212; like oil, coal, and natural gas &#8212; and renewable sources like wind, solar, geothermal, and hydropower. These primary sources <strong>can be converted<\/strong> to secondary energy source, so-called <strong>energy carriers<\/strong>. Primary energy sources can be divided into:<\/p>\n<ul>\n<li>Non-renewable sources\n<ul>\n<li>Fossil fuels\n<ul>\n<li>Oil<\/li>\n<li>Coal<\/li>\n<li>Natural gas<\/li>\n<\/ul>\n<\/li>\n<li>Mineral fuels\n<ul>\n<li>Natural Uranium<\/li>\n<li>Natural Thorium<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li>Renewable sources\n<ul>\n<li>Solar energy<\/li>\n<li>Wind energy<\/li>\n<li>Hydro and tidal energy<\/li>\n<li>Geothermal energy<\/li>\n<li>Biomass energy (if sustainably exploited)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>Secondary Energy Sources &#8211; Energy Carriers<\/h3>\n<p><strong>Secondary energy sources<\/strong>, also called <strong>energy carriers<\/strong>, are derived from the transformation of primary energy sources. They are called energy carriers because they move energy in a useable form from one place to another. The well-known energy carriers are:<\/p>\n<ul>\n<li><strong>Electricity<\/strong><\/li>\n<li><strong>Petrol<\/strong><\/li>\n<li><strong>Hydrogen<\/strong><\/li>\n<\/ul>\n<p><strong>Electricity<\/strong> and <strong>hydrogen<\/strong> are made from primary energy sources such as coal, natural gas, nuclear energy, petroleum, and renewable energy sources. Electricity is particularly useful since it has <strong>low entropy<\/strong> (is highly ordered) and can be converted into other forms of energy very efficiently. Simply, we cannot say that hydrogen has the potential to offset fossil fuels.<\/p>\n<p>Secondary energy sources are used because their use is easier than using a primary energy source. For example, using electricity for lighting is safer than using petroleum in candles or kerosene lamps.<\/p>\n<p>On the other hand, any conversion of primary energy to energy carrier is associated with some inefficiency. Therefore when dealing with the secondary energy source, we always have to consider the way, how the carrier was made.<\/p>\n<\/div>\n<div   id="8n9s8rpp6h"    class=\"su-divider su-divider-style-dotted\" style=\"margin:20px 0;border-width:2px;border-color:#999999\"><\/div>\n<div   id="8n9s8rpp6h"     class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights \"><div   id="8n9s8rpp6h"     class=\"inside-grid-column\">\u00a0 <div   id="8n9s8rpp6h"    class=\"su-accordion su-u-trim\"><div   id="8n9s8rpp6h"    class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\"><div   id="8n9s8rpp6h"    class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>References:<\/div><div   id="8n9s8rpp6h"    class=\"su-spoiler-content su-u-clearfix su-u-trim\"><strong>Reactor Physics and Thermal Hydraulics:<\/strong>\n<ol>\n<li>J. R. Lamarsh, Introduction to Nuclear Reactor Theory, 2nd ed., Addison-Wesley, Reading,\u00a0MA (1983).<\/li>\n<li>J. R. Lamarsh, A. J. Baratta, Introduction to Nuclear Engineering, 3d ed., Prentice-Hall, 2001, ISBN: 0-201-82498-1.<\/li>\n<li>W. M. Stacey, Nuclear Reactor Physics, John Wiley &amp; Sons, 2001, ISBN: 0- 471-39127-1.<\/li>\n<li>Glasstone, Sesonske. Nuclear Reactor Engineering: Reactor Systems Engineering,\u00a0Springer; 4th edition, 1994, ISBN:\u00a0978-0412985317<\/li>\n<li>Todreas Neil E., Kazimi Mujid S. Nuclear Systems Volume I: Thermal Hydraulic Fundamentals, Second Edition. CRC\u00a0Press; 2\u00a0edition, 2012, ISBN:\u00a0978-0415802871<\/li>\n<li>Zohuri B., McDaniel P. Thermodynamics in Nuclear Power Plant Systems. Springer; 2015, ISBN:\u00a0978-3-319-13419-2<\/li>\n<li>Moran Michal J., Shapiro Howard N. Fundamentals of Engineering Thermodynamics, Fifth Edition,\u00a0John Wiley &amp; Sons, 2006, ISBN:\u00a0978-0-470-03037-0<\/li>\n<li>Kleinstreuer C. Modern Fluid Dynamics. Springer, 2010,\u00a0ISBN 978-1-4020-8670-0.<\/li>\n<li>U.S. Department of Energy, THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW. DOE Fundamentals Handbook, Volume 1, 2, and 3. June 1992.<\/li>\n<\/ol>\n<\/div><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-divider su-divider-style-dotted\" style=\"margin:15px 0;border-width:2px;border-color:#999999\"><\/div><\/div><\/div><div   id="8n9s8rpp6h"    class=\"su-divider su-divider-style-default\" style=\"margin:15px 0;border-width:2px;border-color:#999999\"><\/div><div   id="8n9s8rpp6h"     class=\"lgc-column lgc-grid-parent lgc-grid-33 lgc-tablet-grid-33 lgc-mobile-grid-100 lgc-equal-heights \"><div   id="8n9s8rpp6h"     class=\"inside-grid-column\"><\/div><\/div><div   id="8n9s8rpp6h"     class=\"lgc-column lgc-grid-parent lgc-grid-33 lgc-tablet-grid-33 lgc-mobile-grid-100 lgc-equal-heights \"><div   id="8n9s8rpp6h"     class=\"inside-grid-column\">\n<h2>See above:<\/h2>\n<p>Thermodynamics<a href=\"http:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/\" class=\"su-button su-button-style-flat\" style=\"color:#606060;background-color:#ffffff;border-color:#cccccc;border-radius:10px;-moz-border-radius:10px;-webkit-border-radius:10px\" target=\"_self\"><span style=\"color:#606060;padding:7px 20px;font-size:16px;line-height:24px;border-color:#ffffff;border-radius:10px;-moz-border-radius:10px;-webkit-border-radius:10px;text-shadow:0px 0px 0px #000000;-moz-text-shadow:0px 0px 0px #000000;-webkit-text-shadow:0px 0px 0px #000000\"><i class=\"sui sui-link\" style=\"font-size:16px;color:#5d5d5d\"><\/i> <\/span><\/a><\/p><\/div><\/div><div   id="8n9s8rpp6h"     class=\"lgc-column lgc-grid-parent lgc-grid-33 lgc-tablet-grid-33 lgc-mobile-grid-100 lgc-equal-heights \"><div   id="8n9s8rpp6h"     class=\"inside-grid-column\"><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"<p>The term energy is very broad, and it has many definitions. Technically, energy is a scalar physical quantity that is associated with the state of one or more objects. Energy is generally defined as the potential to do work or produce heat. Sometimes it is like the \u201ccurrency\u201d for performing work. You must have the &#8230; <a title=\"What is Energy &#8211; Physics\" class=\"read-more\" href=\"https:\/\/sitepourvtc.com\/nuclear-engineering\/thermodynamics\/what-is-energy-physics\/\" aria-label=\"More on What is Energy &#8211; Physics\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":16012,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"generate_page_header":""},"_links":{"self":[{"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/pages\/16542"}],"collection":[{"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/comments?post=16542"}],"version-history":[{"count":4,"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/pages\/16542\/revisions"}],"predecessor-version":[{"id":34597,"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/pages\/16542\/revisions\/34597"}],"up":[{"embeddable":true,"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/pages\/16012"}],"wp:attachment":[{"href":"https:\/\/sitepourvtc.com\/wp-json\/wp\/v2\/media?parent=16542"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}