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Environmental Science & Natural Resources Student Edition Developed by the Curriculum and Instructional Materials Center for the Division of Agricultural Education Oklahoma Department of Career and Technology Education 13-02456789 Free Sample Provided by CIMC www.okcimc.com AG3042 Upfront Environmental Science & Natural Resources Copyright 2013 Project Manager: Jamie Church Writers: Beth Ann Fulgenzi Karen Gibson Julie Milligan Jeffrey Whisenhunt Cover Design: Kim Hale/Creative Services Staff Kathy Wood & Jamie Church _ Graphics: Kim Hale/Creative Services Staff _ Kathy Wood _ Book Designers: Kathy Wood _ Jamie Church Validation Committee: Arnold Bourne Bryan Craig Keith Dillingham Danny Griffin Lindsey Hoerbert Rick McElhaney Kurt Murray Randy Pullan Oklahoma Department of Career and Technology Education Curriculum and Instructional Materials Center All rights reserved. Printed in the United States of America by the Oklahoma Department of Career and Technology Education Stillwater, OK 74074-4364 This publication, or parts thereof, may not be reproduced in any form photographic, electrostatic, mechanical, or any other methods for any use including information storage and retrieval, without written permission from the publisher. Use of commercial products in these instructional materials does not imply endorsement by the Oklahoma Department of Career and Technology Education. Web site addresses were accurate and all content on referenced web sites was appropriate during the development and production of this product. However, web sites sometimes change; the CIMC takes no responsibility for a site’s content. The inclusion of a web site does not constitute an endorsement of that site’s other pages, products, or owners. You are encouraged to verify all web sites prior to use. The Oklahoma Department of Career and Technology Education does not discriminate on the basis of race, color, national origin, sex/gender, age, disability, or veteran status. This publication could not have been printed without the expertise and commitment of the Printing Plant staff under the supervision of Danny Darrow. Delivery of the final product was accomplished through the excellence of the Curriculum Customer Service staff, under the direction of Lana Austin, and the CIMC Warehouse staff, under the direction of Hank Martin. Cover photos purchased from Thinkstock Photos. ii Free Sample Provided by CIMC www.okcimc.com Upfront Table of Contents UNIT 1 Environmental Safety and Regulations Environmental Safety • Fire Safety • Biohazard Materials • Protection of Natural Resources • Environmental Laws & Regulations • Natural Resource Mitigation................................................................................................................................ 1 UNIT 2 Environmental Resource Management Renewable and Non-renewable Natural Resources • Preservation vs. Conservation • Interdependence within an Ecosystem • Managing and Preventing Pollution • Solid Waste Management • Methods and Materials for Recycling........... 17 UNIT 3 Energy Conservation Energy Forms and Usage • Energy Sources • Economic Impact of Energy • Environmental Impact • Efficiency and Conservation....................................................................................................................................................... 31 UNIT 4 Soil Conservation and Management Soil and Land Use • Soil Formation • Soil Composition • Soil Particles and Texture • Soil Structures • Soil Profile • Soil Classification • Soil Erosion and Management • Soil Quality........................................................................ 47 UNIT 5 Wetland Management Types of Wetlands • Classifying Wetlands • Benefits of Wetlands • Inhabitants of Wetlands • Importance of Wetland Programs • Delineating a Watershed • Protecting Water Quality................................................................................. 65 UNIT 6 Pasture and Rangeland Management Healthy Rangeland • Range Sites • Managing Pasture and Forage Growth • Native Grasses • Forage Grasses and Legumes • Pasture Utilization • Grazing Practices • Preventing Overgrazing • Grazing Systems • Advantages of Improved Pastures • Renovation of Pasture Land.................................................................................................................. 79 UNIT 7 Forest Ecology Forest Ecology • Parts of a Tree • Measuring Tree Height and Diameter • Woody and Herbaceous Plants • Deciduous and Evergreen Trees • Native vs. Invasive Tree Species • Forest Regions • Characteristics of a Healthy Forest • Forest Stand Improvement • Forest Harvesting and Processing • Diseases and Insects • Damage from Weather and Wildlife • Controlled Burns.......................................................................................... Free Sample Provided by CIMC www.okcimc.com 103 iii Upfront UNIT 8 Wildlife Ecology The Food Chain and Food Web • Wildlife Species • Healthy Wildlife Habitats • Improving Wildlife Habitats • Carrying Capacity and Limiting Factors • Sustainably Harvested Wildlife • Products from Wildlife Species • Dangers to Wildlife Species.................................................................................................................................................... 125 UNIT 9 Hydrologic Principles Water in the United States • Uses and Distribution of Water • Water Biogeochemical Cycle • Surface Water and Groundwater • Point and Nonpoint Source Water Pollution • Riparian Buffer Strips • Watersheds • Water Conservation................................................................................................................................................................. 147 UNIT 10 Aquatic Ecology Types of Streams • Biological Health of a Stream • Aquatic Food Chain and Food Web • Native and Invasive Aquatic Organisms • Water and the Biosphere • Underwater Aquifers and Major Rivers • Source Water Quality............................ 163 UNIT 11 Air Pollution Management Earth’s Atmosphere • Weather Systems and Patterns • Meteorological Effects on Air Quality • Air Pollution Effects on the Environment and Human Health • The Greenhouse Effect • Climate Change • Pollution Control Measures • Improving Air Quality.............................................................................................................................................................. 179 UNIT 12 Recreational Resources Natural Resources for Recreation • Recreational Activities • Governmental Public Recreational Areas • Improving Recreational Opportunities • Boating and ATV Safety • Economic Impact • Principles of Hunting Safety • Hunting and Fishing Rules and Regulations............................................................................................................................. 193 Glossary ....................................................................................................................................................................... 215 Index ............................................................................................................................................................................... 225 iv Free Sample Provided by CIMC www.okcimc.com Energy Conservation 3 Key Terms biomass coal conservation efficiency energy energy consumption fossil fuels geothermal hydropower kinetic energy natural gas nonrenewable energy petroleum potential energy propane renewable energy solar uranium wind Objectives •• •• •• •• Discuss the forms and usage of energy. Classify energy resources as renewable or nonrenewable. Discuss the value of energy sources to the economy. Evaluate the impact of conventional and alternative energy sources on the environment. •• Discuss conservation measures to reduce energy consumption. Free Sample Provided by CIMC www.okcimc.com Environmental Science & Natural Resources Energy is a fundamental component of human life and is essential for the advancement of society. Energy is used in all aspects of our lives, from turning on the light in our house to powering the vehicles we drive. Can you imagine your life without energy? Just think how frustrating it is when the electricity is off at your house. As a society, we are accustomed to having energy at our fingertips, whether it is flipping on the light switch or filling up the car with gasoline. Energy Forms and Usage Energy is defined as the power derived from the use of physical or chemical resources. It comes in many forms and can be categorized as either potential or kinetic. Potential energy is also known as stored energy. This stored energy is a result of an object’s position. Chemical, mechanical, nuclear and gravitational energy are all forms of potential energy. Kinetic energy is energy of motion. There are numerous forms of kinetic energy. Electrical, radiant, thermal, motion and sound energy are all a result of movement. Energy Forms Potential Energy Forms Examples Kinetic Energy Forms Examples Chemical Energy Stored in atoms and molecules • Biomass • Petroleum Electrical Energy Movement of electrons • Electricity • Lightning Stored Mechanical Energy Stored in objects • Stretched Rubber Band • Spring Radiant Energy Electromagnetic energy • Light • Solar Energy Nuclear Energy Stored in the nucleus of an atom • Fission • Fusion Thermal Energy Internal energy • Heat • Geothermal Energy Gravitational Energy Position or place • Hydropower • Rock on a hill Motion Energy Movement of objects • Wind • Riding a bike Sound Energy Movement of energy through waves • Tuning fork • Speaker 32 Free Sample Provided by CIMC www.okcimc.com Unit 3 Energy Conservation Energy cannot be created or destroyed, only transformed or converted. This means energy is constantly changing. Energy can be changed from potential to kinetic. Think about the process of lighting a match. The combustible material on the tip of the match is an example of potential energy. There is the potential for energy to be created in the right conditions. As the tip of the match is struck against the box, it changes to kinetic energy. The heat produced from the match is movement of molecules. This is just one example of changing energy from potential to kinetic. Energy can also be changed from one form of kinetic energy to another. An example of this change is a toaster. Electrical energy is changed into thermal energy. No matter the source, great technological advancements have been made in changing energy for human use. Using energy to do work is not a new concept. From Primary Energy Use by Sector, 2011 early on, humans produced energy by utilizing their Quadrillion Btu resources. For early civilizations, fire was one of the Residential & first energy sources. Wood was used as the fuel source 10.6 Commercial and provided energy to cook, produce light and heat living spaces. Windmills have been used for centuries Industrial 20.4 to capture the power of the wind allowing humans to pump water and now produce electricity. By 1930, Transportation 26.9 half of all Americans were using coal to heat their homes and buildings. Regardless of where the energy comes from, Americans use it daily from numerous Electric Power 39.6 sources. The amount of energy used by a person is 0 5 10 15 2025303540 called energy consumption. The U.S. Department of Source: U.S. Energy Information Administration, Monthly Energy Energy classifies users into four categories – residential/ Review, Table 2.1 (March 2012), preliminary 2011 data. commercial, industrial, transportation, and electric power. Residential/commercial consumers utilize energy for heating, cooling, lighting and operating appliances within their homes and businesses. Industrial energy consumption is utilized to manufacture products, while transportation energy consumption refers to the fuel or other energy sources used to power vehicles. The electric power sector includes power generating facilities that use a variety of sources such as coal, natural gas, and renewable resources to create electricity for use. For this reason, the electric power sector accounts for the largest amount of energy use. Energy prices have always dictated the consumption of energy by Americans. When energy prices are high, people tend to use less energy. Improved technologies have also allowed people to use less energy. Vehicles, appliances, homes and many other products have become more energy efficient. People have also become more aware of the impact of producing energy on the environment. These factors affect how much energy people use. Free Sample Provided by CIMC www.okcimc.com 33 Environmental Science & Natural Resources Energy Sources There are two categories of energy sources – renewable and nonrenewable. A renewable energy source is one that can be easily replenished. On the other hand, nonrenewable energy sources are ones that can be used up and must be released by human activity. There are pros and cons to each energy category. Renewable energy causes very little pollution; nonrenewable sources can release pollution into the environment. There is an abundant quantity of renewable sources, but the initial cost to utilize them is high. Although there is a limited supply of the different forms of nonrenewable energy, they are less expensive and easy to use. It is also economical to convert from one type of energy to another. Both renewable and nonrenewable energy sources can produce secondary energy sources. Electricity and hydrogen are two secondary energy sources. Primary Energy Use by Source, 2011 Quadrillion Btu and Percent Total U.S. = 97.5 Quadrillion Btu Natural Gas 24.9 (25.5%) Petroleum 35.3 (36.2%) Coal 19.9 (20.4%) Renewable Energy 9.1 (9.3%) Nuclear Electric Power 8.3 (8.5%) Source: U.S. Energy Information Administration, Monthly Energy Review, Table 1.3 (March 2012), preliminary 2011 data. Renewable Energy Sources There are five major renewable energy sources. These include biomass, hydropower, wind, geothermal and solar. These sources are also known as alternative energy sources. Renewable energy sources typically provide electricity for use. Biomass Biomass is organic matter utilized for energy. The stored energy in biomass originates with the sun. Plants are able to convert radiant energy into chemical energy through the process of photosynthesis. The carbohydrates produced through photosynthesis supply the plants with energy. Humans and animals that eat the plants are also able to utilize the stored energy. Four types of biomass are used today – wood and agricultural products, solid waste, landfill gas and biogas, and alcohol fuels. 34 Free Sample Provided by CIMC www.okcimc.com Unit 3 Thinkstock Photo Energy Conservation Wood was one of the first uses of biomass as an energy source. People have been using wood as a source of energy for thousands of years. Today, wood still accounts for approximately 46 percent of biomass energy. Wood waste from paper mills and saw mills is often used to supplement power to these industries. Utilizing waste from wood-based industries allows companies to save on disposal costs and reduce their energy bills. The second type of biomass is solid waste. Burning trash allows waste to be converted into usable energy. Power plants called waste-to-energy plants burn trash for energy. Although it costs more to make electricity through this type of power plant, it will reduce the trash dumped in landfills by 60 to 90 percent. One ton of garbage can produce as much heat energy as 500 pounds of coal. The third type of biomass is also related to trash. Landfill gas and biogas are produced as bacteria, and fungi eat dead plants or animals. During this process, methane gas is produced. Recent regulations now require landfills to collect this gas to be purified and used as a fuel. Much attention has been given to alcohol fuels in recent years. Research has lead to two main biomass sources – ethanol and biodiesel. Fermenting starches and sugars found in plants followed by distilling makes ethanol. Although most ethanol is produced from corn, any source of organic material that contains cellulose, starch or sugar can be used for ethanol production. Many gas stations now sell fuel that contains 10 percent ethanol. Biodiesel consumption has not increased as quickly as ethanol, Fuel containing ethanol can be found at many gas stations. but is also not publicly offered at fuel Thinkstock Photo stations. It is becoming one of the fastest growing alternative transportation fuels and is practical for fleet use. Biodiesel is made by a chemical reaction between alcohol and vegetable oil, animal fat or grease. Biodiesel today is typically made using soybean oil. One concern for both ethanol and biodiesel is the use of agricultural land to produce corn and soybeans for these products rather than for food. Free Sample Provided by CIMC www.okcimc.com 35 Environmental Science & Natural Resources Hydropower Hydropower is energy produced by the movement of water. The Greeks used water wheels over 2,000 years ago to grind wheat into flour. Today energy is produced from the flow of water at hydropower plants. Hydropower plants are usually located on a river with a dam. This allows for the control of the water, which can be released when electricity needs to be produced. The motion of the water spins a large turbine, converting the energy from motion energy into mechanical energy. The turbine is attached to a generator, which then produces electricity. Hydropower relies on the water cycle. The sun’s energy will evaporate water from oceans, lakes and rivers. Once the evaporated water reaches the cooler air in the atmosphere, it forms clouds or condenses. Eventually the clouds will produce precipitation such as rain or snow, which will replenish the oceans, lakes and rivers with water. This constant replenishing allows hydropower to be a renewable energy source. Turbines change mechanical energy into electricity Thinkstock Photo Wind Wind is the movement of air that is caused by the uneven heating of the Earth’s surface by the sun. Wind is another source of energy that people have used for centuries. One of the earliest uses of wind energy was to sail ships. Then people began using windmills to harness the power of the wind. Holland became one of the world’s most industrialized countries due to the use of windmills in the 17 th century. Early American ranchers used windmills to pump water for their livestock. Rural areas depended on small windmills to generate electricity until power lines began to transport electricity to those areas in the 1930s. With the expansion of power lines, windmills became less prominent until the oil shortages in the 1970s. The awareness of alternative energy sources has allowed for the windmill to become an important avenue to generate electricity once again. 36 Wind turbines generate electricity Thinkstock Photo Free Sample Provided by CIMC www.okcimc.com Unit 3 Energy Conservation Today wind turbines harness the wind and convert it to electricity. The wind turbines come in a variety of shapes and sizes. Some are smaller and are used to supplement power to a home. Others are large enough to generate power for utility companies to sell. The different shapes of the blades allow for efficient use at different wind speeds. When wind turbines are grouped together to produce a large amount of electricity, they are called wind farms. The location of a wind farm is researched extensively prior to placing the turbines. Wind speed and direction must be studied to provide for the optimum placement. Other factors such as weather, accessibility, wildlife, and location of the power grid must also be considered when choosing a location for a wind farm. Wind energy is a feasible, cost-effective alternative to conventional power plants. It is currently the fastest growing energy technology in the world. Wind is a clean fuel that does not have any serious negative impact on the environment. Many utility companies offer customers the option to pay a premium for electricity generated by wind. CAREER CONNECTIONS: Wind Turbine Technician Wind farms are springing up along the horizon. Thousands of modern day windmills or wind turbines are being erected across the United States. With new technologies come new careers. The increasing demand for wind energy has produced a need for wind technicians. Wind technicians are responsible for routine maintenance on the wind turbines. This includes component replacement, circuit troubleshooting and routine maintenance. Routine maintenance includes oil changes, bolt torquing, accumulator recharging, hydraulic system repair and electrical system troubleshooting. Most tasks are performed within the tower. Technicians are required to scale the tower and must undergo a climb test. Safety is a priority for wind technicians. When climbing the tower, technicians are required to use a safety harness for “climb assist”. This allows techs to climb the tower with less effort. Technicians also have to be prepared to work in tight spaces. Thinkstock Photos To become employed as a wind technician, a person should complete a wind energy training program. Many companies also provide on-the-job training. The starting salary for entry-level wind technicians is $55,000. Once experience is gained, a technician can expect a raise. Senior technicians and operations managers can make between $95,000 and $110,000 per year. Source: Bureau of Labor Statistics, http://www.bls.gov/green/wind_energy Free Sample Provided by CIMC www.okcimc.com 37 Environmental Science & Natural Resources Geothermal The heat from the Earth’s core generates geothermal energy. This energy is recovered as steam or hot water and then used for heating or electricity. The Earth’s core has two layers, a solid iron core and an outer core of hot molten iron called magma. Surrounding the core is the mantle, which is made of magma and rock. The crust is the outermost layer of the Earth. The crust is broken into pieces called plates. The plates push against each other and cause cracks or faults in the crust. The faults allow magma to rise into the crust towards the surface of the Earth. When the magma reaches the surface, a volcano is formed. If the magma remains trapped within the crust, it can heat underground water allowing for the creation of hot springs. It also allows for the formation of deep geothermal reservoirs. Most of the geothermal activity is located in the area known as the Ring of Fire – a ring of hot spots around the Pacific Ocean. Many ancient people used hot mineral springs as a source of energy for bathing, cooking and heating. Today people enjoy hot mineral springs for recreation as well as for commercial and industrial heating. Wells are drilled to capture the energy found in the geothermal reservoirs. Steam and heat drive turbines in electrical power plants. The energy is converted from thermal energy to electrical energy. Geothermal power from the Earth’s core Thinkstock Photo Solar Solar energy is radiant energy from the sun and is by far the Earth’s most abundant energy source. The sun is a large ball of gases. Hydrogen atoms fusing to form helium through the process of nuclear fusion produce energy. The sun produces large amounts of energy, but only a small portion emitted into space actually reaches the Earth’s surface. Yet the amount of energy that does make it to Earth is still plentiful. The energy that reaches Earth is reflected back into space, used to evaporate water or absorbed by vegetation. The sun’s energy can be captured to provide heat and electricity. 38 Solar power panels capture the sun’s energy. Thinkstock Photo Free Sample Provided by CIMC www.okcimc.com Unit 3 Energy Conservation KNOWLEDGE CHECK 1. 2. 3. 4. What are the five major renewable energy sources? Why is there a concern about ethanol production? What resource does hydropower rely on? How do people enjoy geothermal energy? Nonrenewable Energy Sources The majority of our energy comes from five major nonrenewable energy sources. Three of the sources, petroleum, natural gas and coal, are considered fossil fuels. Fossil fuels are formed by natural processes that take millions of years, which is why they are considered nonrenewable. The other two sources are uranium and propane. The United States and much of the world rely highly on nonrenewable sources to provide energy. Petroleum Petroleum or crude oil is a naturally occurring fossil fuel that was formed from the remains of plants and animals. Sand and silt covered the decaying plants and animals. Over millions of years, heat and pressure caused a chemical change, and crude oil was formed. Oil has been used for hundreds of years for light and heat. In the late 1800s and early 1900s, the demand for gasoline, a product of crude oil, increased because of the invention of the automobile. From 1950 to now, oil has become the most used energy source. Oil pump jack Thinkstock Photo Petroleum is located under the Earth’s surface in reservoirs and is retrieved by drilling. Scientists and engineers study rock formations to determine the potential of finding petroleum. In recent years, new technology and cost effective methods have increased production in the United States. Today’s wells average over 5,000 feet deep. An average oil well will produce 10 barrels per day. The top producing states are Texas, Alaska, California, North Dakota and Oklahoma. These states produce over 50 percent of U.S. crude oil. Free Sample Provided by CIMC www.okcimc.com 39 Environmental Science & Natural Resources Once the crude oil has been pumped to the Earth’s surface, it will be transported to an oil refinery to be processed. It cannot be used in its natural state. At the oil refinery, the crude oil is cleaned and separated into the usable fuels and by-products. Usable fuels that are produced include gasoline, diesel, and jet fuel. Some examples of by-products that are produced include ink, crayons, tires, deodorant, eye glasses and ammonia. These are just a few of the products that are petroleum based. Many items used on a daily basis are derived from petroleum. Oil refinery Thinkstock Photo Natural Gas Natural gas is a colorless, odorless and tasteless gas that is often found when drilling for oil. The main ingredient in natural gas is methane. Natural gas is also formed when pressure and heat change the organic matter made up of decaying plants and animals that is trapped under layers of sediment, rock and soil. Natural gas was once considered a nuisance when drilling for oil, but now has many uses. Natural gas was first used in America to power street lamps in the early 1800s, but over the past 40 years it has become a major source of energy. Natural gas use is now very common in the United States. Approximately 25% percent of energy used comes from natural gas. Natural gas is used in homes to power stoves, water heaters, clothes dryers, and home heating systems. It is also used by the industrial sector to produce plastics, steel, man-made fibers, paint and numerous other products. Natural gas is used to produce electricity and is the second largest producer after coal. Most recently, natural gas is used as a transportation fuel (compressed natural gas) powering vehicles that have been modified with a special fuel tank and carburetor. Natural gas is transported through a pipeline infrastructure. Thinkstock Photo Natural gas production begins with geologists who study the rock structure and formation to determine the location of natural gas. If the presence of natural gas is promising, exploratory wells will be drilled. Many times, natural gas is found at the same location as petroleum deposits. 40 Free Sample Provided by CIMC www.okcimc.com Unit 3 Energy Conservation Coal Coal is a combustible sedimentary rock that has been formed from the compression of plant material over millions of years. The plant material in swamp areas began to decay. Layers of sediment, rock, soil and water collected over the layer of plant vegetation. Heat and pressure from the multiple layers caused a chemical change and resulted in the formation of coal. Coal is the most abundant source of nonrenewable energy in the United States. Seams of coal can be found deep underground or close to the surface. In either case, coal must be mined to be removed from the ground. In the United States, many of the coal beds are near the Earth’s surface. Approximately two-thirds of the coal production is a result of surface mining. If the coal is buried more than 200 feet under the ground’s surface, underground mining is used. During the process of surface mining, the topsoil and other layers of rock are removed by large equipment to expose the coal. Upon completing the mining process, the rocks, soil and topsoil are replaced. Underground mining requires miners to go below the surface of the Earth. Elevators and mine shafts are used to remove the coal. Surface mining is less expensive than underground mining. With improved technology, the production of one miner has tripled since the late 1970s. Coal was used very little after it was first discovered. Early settlers in the United States relied on hydropower from water wheels and energy from wood to provide their Coal is processed and then distributed, often by rail cars. power. During the mid 1700s, commercial production of Thinkstock Photo coal in the United States began. By the early 1800s, coal was the principal fuel for steam-powered locomotives and steamships. By the 1830s, all American locomotives were converted to use coal. In the late 1800s, Thomas Edison developed an electric generating station powered by coal. Coal was the energy powerhouse for the United States by the 1900s and remained the number one energy source until demand for petroleum products increased. Free Sample Provided by CIMC www.okcimc.com 41 Environmental Science & Natural Resources Uranium Uranium is a naturally occurring metallic element that is radioactive and can be found all over the world. Uranium has properties that allow it to be used as a fuel by nuclear power plants. There are three types of uranium – uranium-234, uranium-235, and uranium-238. Uranium-235 is the type used in nuclear plants. Nuclear energy is derived from breaking the bonds in the nucleus of an atom. Uranium-235 has atoms that are easily split. The process of breaking these bonds is known as nuclear fission. Nuclear fission releases a large amount of energy and is currently the only process used by nuclear power plants. Uranium is found in nature and must be mined. Most uranium in the United States is found in the western part of the country, although a large portion of uranium used is imported. It is mined by either surface or underground mining techniques. Once the uranium is mined, the uranium-235 is extracted and processed. After processing it is placed in a nuclear reactor. The fission process will produce energy in the form of heat, which will cause water to boil and produce steam. The steam will power large turbines, which in turn will drive generators that produce electricity. Nuclear energy plants require large amounts of water for powering generators. Thinkstock Photos 42 Nuclear energy is a relatively new energy source. In the 1930s, scientists discovered the nucleus of an atom as well as how to split it through the process of fission. During World War II, this technology was used to create the first nuclear bomb. In 1946, the Atomic Energy Act was passed to allow for the exploration of non-destructive uses for nuclear energy. The first full-scale U.S. nuclear power plant was built in 1957 in Pennsylvania. The nuclear power industry experienced rapid growth from 1965 to 1975. There was a time period where the public opposed using nuclear technology, and until recently there were no plans to build new plants. Nuclear energy is once again being considered for expansion. Free Sample Provided by CIMC www.okcimc.com Unit 3 Energy Conservation Propane Propane is a colorless, odorless by-product of natural gas and petroleum. Propane was formed through the same process as petroleum and natural gas and is found with those deposits under the Earth’s surface. Propane is considered a liquified petroleum gas (LPG). Propane is the most common type of LPG used in the United States. Propane was discovered in the early 1900s while people were attempting to store gasoline. The gasoline would evaporate under normal conditions. A U.S. scientist discovered that the evaporating gases could be changed from a gas to a liquid by compressing the gases and decreasing the temperature. He then developed a system to store the liquid gas. Since propane is more compact as a liquid, this is how it is stored and transported. To use propane, it must be returned to a gas. Containers that hold liquid petroleum gases are under pressure and will have a valve that, when opened, releases and returns it to its gaseous state. Many people in the United States use propane to heat their homes and water, and fuel fireplaces, barbecue grills and appliances. Many rural residents use propane as their main source of energy to heat their homes. Propane is also used in business and industry, for heating, cooling, operating machinery, and manufacturing products. Propane can also be used as a transportation fuel. Businesses and school districts that have fleets of vehicles often use propane instead of gasoline. Because of the many uses, the United States uses more propane than any other country. Propane bottles are refilled from a larger storage container. Thinkstock Photos Economic Impact of Energy The production and use of energy affects the U.S. economy by providing jobs as well as revenues to state and federal governments. Both renewable and nonrenewable energy sources contribute to the economy. Not only does the energy industry provide tax income to the state and federal governments, it also impacts local economies. With greater focus being put on clean energy, the alternative energy industry is contributing more significantly to the economy in the form of jobs, income and tax revenue. As with all products, energy prices fluctuate with supply and demand. When gasoline prices rise, consumer spending tends to decrease. According to the Energy Information Administration, natural gas and renewable energy usage will increase in the next 15 years, while demand for energy from oil will decrease. Even though we may see a decrease in petroleum as an energy source, it will not completely go away. To supply the energy needs of consumers, a combination of renewable and nonrenewable energy will be necessary. Free Sample Provided by CIMC www.okcimc.com 43 Environmental Science & Natural Resources Environmental Impact Each energy source has a different impact on the environment. Some have a more significant impact than others. In recent years, people have become more aware of the effect the energy industry has on the environment. The focus is on reducing the environmental impact while providing the needed energy. Both renewable and nonrenewable energy sources have positives and negatives. The sources of renewable energy will not have a shortage. They are just that – renewable. We can produce more biomass by planting. The down side to utilizing biomass is the large amount of energy required to grow crops. Biomass does produce small amounts of harmful emissions; however, those emissions are less than oil and petroleum. Geothermal power plants have very little impact on the environment although they also produce small amounts of carbon dioxide. Hydropower does not cause any pollution, but it does impact the environment. Hydroelectric Hydroelectric dam Thinkstock Photo power plants can change the natural flow of rivers or streams. It also can impact the migration of fish as well as force people to relocate. Wind power is the most environmentally friendly source of energy. Wind turbines have a very small impact on the land in which they are located. Some individuals do not like the appearance or aesthetics of wind turbines, while others see them as a sign of progress. Technology has also improved to reduce the amount of noise produced by the turbines. Geothermal and solar energy sources also produce very little or no emissions. Solar energy does require use of some toxic chemicals that could have a negative effect on the environment if not used properly. Overall, renewable energy sources are environmentally friendly. With the emphasis on clean energy, technologies will continue to improve to reduce any negative impact on the environment. Nonrenewable energy sources have a history of impacting the environment negatively. Mining coal can cause air, water and land pollution. People may have a critical perception of the petroleum industry because of oil spills. The oil and natural gas industries both disrupt the land by clearing for roads and a drill pad as well as causing emissions. The process of mining uranium requires a large amount of energy. However, the technology to make nonrenewable energy sources more environmentally friendly has greatly improved. Progress has been made towards “clean coal” technology. Emphasis is put on minimizing the impact of the oil and gas industry on the land and environment. The land used for mining can be returned to its original state or reclaimed. Overall, each energy source benefits from improved technology to minimize the effects on the environment. 44 Free Sample Provided by CIMC www.okcimc.com Unit 3 Energy Conservation Efficiency and Conservation When using energy, two concepts need to be considered – conservation and efficiency. Conservation is the practice of preventing wasteful overuse of energy. It is important for people to make the effort to conserve energy. Not only does it impact the environment, it also saves money. Saving energy has become an important topic in recent years. Consumers are more aware of the energy used in homes today. Simple things that reduce the energy used include turning off the lights when not in a room or changing the air filter on the heat and air unit. Simply put, conserving is using less energy. Energy Conservation Methods Utilize a programmable thermostat. Wash laundry on cold or warm instead of hot. Turn down your water heater. Run the dishwasher only when full. Take shorter showers. Turn off lights, televisions or other appliances when not in use. When possible, walk or bike for transportation. Consider fuel mileage when purchasing a car. Energy efficiency is the concept of maximizing energy production with the least amount of waste. Technology has improved and the products consumers use are more efficient than ever. Products such as washing machines, refrigerators, windows and many others receive an ENERGY STAR® rating. This rating allows consumers to compare products or appliances to make wise purchasing decisions. Consumer education will result in lower energy use over time. KNOWLEDGE CHECK 1. 2. 3. 4. 5. Why are fossil fuels considered nonrenewable? How are petroleum and natural gas similar? How is a majority of coal mined? Why is propane considered a liquefied petroleum gas? Do renewable or nonrenewable resources have less of an impact on the environment? Free Sample Provided by CIMC www.okcimc.com 45 Environmental Science & Natural Resources Unit Summary The energy industry is essential for the growth and development of the United States. Energy is used in all aspects of human life. Our ability to do work is based on our ability to utilize our resources. With the development of new technologies, nonrenewable energy sources have been improved. The environmental impact of petroleum, natural gas, coal, uranium and propane has been reduced while efficiency has increased. New technologies have also allowed for the advancement of renewable energy sources. Biomass, hydropower, wind, geothermal and solar energy each play an important role in contributing to the overall energy available for use. As the energy industry continues to grow, it is important to focus on providing “clean energy”. Humans will continue to utilize resources to provide an economical source of energy. By becoming environmentally conscious consumers, we can assist in maintaining the cost of energy as well as using it efficiently. Unit Review 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 46 Outline the different types of potential and kinetic energy. Compare renewable energy to nonrenewable energy. Define energy consumption. Describe each of the five types of renewable energy and nonrenewable energy. Explain advantages and disadvantages of renewable energy. Explain advantages and disadvantages of nonrenewable energy. Describe the impact of the energy industry on the environment. Explain the importance of energy to the economy. Discuss the difference between energy conservation and energy efficiency. How can consumers conserve energy? Free Sample Provided by CIMC www.okcimc.com