Introduction to Engineering and Technology Concepts Unit Three Chapter Two – Energy

Instructions for Success: Each chapter of every unit will begin with a “Mindjog.” This is a warm up question that you should answer in your workbook in the proper chapter. Please take notes as you move through the presentations in the notebook that has been provided. Sections will come up in each presentation with an assignment notice. Turn to the section detailed on the slide in your workbook and complete the assignment before proceeding. Good luck!

Objective Students will define sources of energy and confirm whether or not those sources can be replaced once utilized.

Mindjog! On your worksheet, please respond to the following question: “Explain, in your own words, how without energy there would be no technology.”

Quick Review In the last chapter, we defined energy as the ability to do work. The concept of technology is anything that makes our lives easier…it does the work for us to a certain extent. Therefore, without energy, humans could not work on the development of technology that in turn could not work to benefit our needs (Wright, 2004).

Quick Review (continued) We also stated that energy is in two forms: kinetic and potential. Kinetic energy is energy that being used. Potential energy is energy that is being stored. Think of a battery…alone the battery has the potential to be transformed and used. When placed in a device that runs on battery power, the energy becomes kinetic (Wright, 2004).

It’s the Law Finally, we noted that energy cannot be created or destroyed. Therefore, energy can only be converted from one form to another. Its general forms are as follows: Mechanical Radiant Chemical Thermal Electrical Nuclear (Wright, 2004)

Mechanical Energy A familiar form, mechanical energy is produced by the motion of technological devices (Wright, 2004).

Radiant Energy Radiant Energy comes in the form of electromagnetic waves (Wright, 2004). The biggest source of radiant energy is the sun (Wright, 2004). In fact, the sun provides most of Earth’s energy (Wright, 2004).

Chemical Energy Chemical energy is stored within a chemical substance. The most common examples of this are petroleum, natural gas, and coal.The most common examples of this are petroleum, natural gas, and coal. Chemical energy is released when a substance is put through a chemical reaction (Wright, 2004).Chemical energy is released when a substance is put through a chemical reaction (Wright, 2004).

Thermal Energy Simply put, thermal energy is from heat. Thermal energy cannot always be seen directly, but have you ever been walking outside on a hot day and seen heated airwaves above the road?Thermal energy cannot always be seen directly, but have you ever been walking outside on a hot day and seen heated airwaves above the road? It is related to the movement of atoms and molecules in a substance (Wright, 2004).It is related to the movement of atoms and molecules in a substance (Wright, 2004).

Electrical Energy ( Wright, 2004).Electrical Energy is associated with electrons moving along a conductor ( Wright, 2004). How often do you utilize electrical energy?How often do you utilize electrical energy?

Nuclear Energy Nuclear Energy is associated with the internal bonds of atoms. Essentially, nuclear energy is harnessed when energy is released during the splitting (fission) or fusing (fusion) of an atom (Wright, 2004).Essentially, nuclear energy is harnessed when energy is released during the splitting (fission) or fusing (fusion) of an atom (Wright, 2004).

Assignment #1 Please turn to the section in your workbook entitled, “Unit Three, Chapter Two – Energy.” Complete the extension questions under the “Assignment #1” header before moving onto the next section of slides.

BEFORE MOVING ON: Did you complete the “Assignment #1” Section under the “Unit Two, Chapter One – Energy” section of your workbook? If you have, please proceed to the next slide.

Sources Now that we have defined the different forms of energy, there needs to be an understanding of exactly what source we are using to harness it. There are three: Exhaustible Renewable Inexhaustible (Wright, 2004)

Exhaustible Exhaustible energy sources are materials that cannot be replaced. The most common are petroleum, natural gas, and coals and can be categorized as fossil fuels. Fossil fuels were once living matter, but millions of years saw the dead plant and animal matter buried under the Earth. Over time, this pressure resulted into solid, liquid, and gaseous fuels. At the rate we are using fossil fuels, more cannot be created before they are all used up (Wright, 2004).

Renewable Renewable energy sources are biological materials that can be grown and harvested. This resource has a direct relation to biotechnology and agriculture, something to be discussed in detail in later units (Wright, 2004). Biotechnology allows for plant and animal gene manipulation for the acquisition and preservation of desired traits. Imagine not running your car on gas, but on ethanol that was created from genetically modified corn!

Inexhaustible Inexhaustible energy resources are part of the solar weather system that exists on Earth (Wright, 2004). This energy will not run out during humanity’s lifetime. These resources are considered to be wind, water, and solar energy (Wright, 2004).

Assignment #2 Please turn to the section in your workbook entitled, “Unit Three, Chapter Two – Energy.” Complete the extension questions under the “Assignment #2” header before moving onto the next section of slides.

BEFORE MOVING ON: Did you complete the “Assignment #2” Section under the “Unit Two, Chapter One – Energy” section of your workbook? If you have, please proceed to the next slide.

Energy Conversion So far, we have defined and discussed energy forms and sources. What we have said is that energy is transformed…and it is through these four ways: Inexhaustible Energy Converters Renewable Energy Converters Thermal Energy Converters Electrical Energy Converters (Wright, 2004)

Inexhaustible Energy Converters In the earlier days, humans only had to power simple technologies. Most of this was done by wind or water…and were converted through devices known as prime movers (Wright, 2004). One of the first prime movers was a sail. It takes the inexhaustible wind resource, harnesses it, and converts it into mechanical energy, pushing the boat forward. Specifically there are wind, water, and solar energy converters known as the windmill, waterwheel, and solar panels, respectively (Wright, 2004).

Renewable Energy Converters Renewable energy comes from these sources: forest product industry, agriculture and food processing, and municipal waste. These are all mainly waste byproducts. Energy is converted through thermochemical or biochemical means. Thermochemical conversion occurs due to a chemical reaction caused by heat. Biochemical conversion occurs through biochemical processes (chemical reactions caused by fungi, enzymes, or microorganisms), anaerobic digestion (a controlled decaying process without oxygen), or fermentation (decomposing material with yeast) (Wright, 2004).

Thermal Energy Converters The industrial revolution used many types of heat engines, but they have since been replaced by electric motors. Consider that many of today’s heat engines are used for transportation purposes and for other reasons such as heating your house (Wright, 2004). For your car, the heat engine burns fuel to produce heat and the heat is converted into mechanical energy. These heat engines can be classified as either internal or external combustion engines. Internal uses expanding gases produced by burning fuel External uses steam (Wright, 2004).

Thermal Energy Converters (continued) When using thermal energy converters to heat a space, there are three types of heat transfers used: Conduction – movement of heat along a solid material or between two solid materials that touch each other and takes place without the flow of matter. This means that energy moves from one area with a higher temperature to the area with the lower one. Convection – the transfer of heat between fluids. Radiation – heat transfer using electromagnetic waves. Also consider heat production, which could be as simple as burning wood in a fireplace to heat the surrounding environment (Wright, 2004).

Electrical Energy Converters Electricity can be generated through different sources, including: Hydroelectric Plant – a water powered plant where dammed water is released through large pipes that turn turbines. Steam Powered Plant – uses fossil fuels or nuclear energy to produce steam to drive the generator's turbine. Nuclear Power Plants – use atomic reactions which produce steam to turn a turbine. Most electric plants have their resource turn a turbine, generating electricity (Wright, 2004).

Assignment #3 Please turn to the section in your workbook entitled, “Unit Three, Chapter Two – Energy.” Complete the extension questions under the “Assignment #3” header before moving onto the next section of slides.

BEFORE MOVING ON: Did you complete the “Assignment #3” Section under the “Unit Three, Chapter Two – Energy” section of your workbook? If you have, please proceed to the next slide.

Chapter Two Completed! Please close this presentation and launch the file entitled, “Chapter 3 – Using Energy.”

References Wright, R. (2004) “Technology” The Goodheart-Willcox Company, Inc.