Module 35

Coal- A solid fuel formed primarily from the remains of trees, ferns, and other plant materials preserved 280 million to 360 million years ago.

The four types of coal are called:

1. Ignite (Also known as lignite, it's a low-grade coal with high moisture content and low energy density.)

2. Sub-bituminous (A type of coal with slightly higher energy content than lignite, but still relatively low compared to bituminous and anthracite.)

3. Bituminous (A widely used coal with moderate energy content and commonly used in electricity generation and industrial processes.)

4. Anthracite (The highest grade of coal with the highest energy content and lowest moisture content, often used for heating and in industrial processes due to its high heat output.)

The Largest coal reserves are in the United States, Russia, China, and India

Coal is the most abundant and dirtiest of all fossil fuels.

The coal formation process is one that is due to pressure and mining

Advantages of Coal:

• Energy-dense

• Plentiful

• Easy to exploit by surface mining

• Needs little refining

• Inexpensive

• Easy to handle and transport

Disadvantages of Coal:

• Contains impurities

• Releases impurities into the air when burned

• Trace metals like mercury, lead, and arsenic are found in coal

• Combustion leads to increased level of air pollutants

• Ash is left behind, leads to possible runoff

• Carbon is released into the atmosphere

Petroleum is a cleaner than coal

Petroleum- A fossil fuel that occurs in underground deposits, composed of a liquid mixture of hydrocarbons, water, and sulfur.

Crude Oil- Slow-flowing, viscous deposits of bitumen mixed with sand, water, and clay.

Petroleum accumulation underground

Advantages of Petroleum:

• Convenient to transport and use

• Relatively energy-dense

• Cleaner-burning than coal

• Oil is used in many other applications

Disadvantages of Petroleum:

• Releases carbon dioxide into the atmosphere

• Possibilities of leaks when extracted and transported

• Runoff enters marine waterways

• Release sulfur, mercury, lead, and arsenic into the atmosphere when burned

Arctic national wildlife refuge (ANWR):

Debates continue over the tradeoff between extracting oil domestically and the consequences for habitat and species living near oil wells or pipelines.

Proponents of exploration suggest that ANWR might yield 25 million gallons to 378 billion gallons of oil and substantial quantities of natural gas.

Natural gas is the cleanest of all fossil fuels

• Natural gas exists as a component of petroleum in the ground as well as gaseous deposits separate from Petroleum.

• Natural gas contains 80 to 95% methane and 5 to 20% ethane, propane, and butane

The two largest uses of Natural Gas in the United States are electricity generation and industrial processes.

Natural gas is also used to manufacture nitrogen fertilizers and in residences for heating homes and cooking.

Advantages of Natural Gas:

• Contains fewer impurities, emits almost no sulphur dioxide or particulates

• Emits only present as much carbon dioxide as coal

  Disadvantages of Natural Gas:

• Methane the escapes into the atmosphere is a potent Greenhouse gas

• Exploration for natural gas can contaminate groundwater

• Shale gas drilling

Oil sands and liquefied coal are also fossil fuels

Oil Sands- Slow-flowing, viscous deposits of bitumen mixed with sand, water, and clay.

Bitumen- A degraded petroleum that forms when petroleum migrates to the surface of Earth and is modified by bacteria.

CTL (coal to liquid)- The process of converting solid coal into liquid fuel.

fossil fuels are a FINITE resource

Energy Intensity- The energy use per unit of gross domestic product.

Our energy use per capita has been dropping but with rising population numbers total energy use continues to rise.

US ENERGY USE PER CAPITA AND ENERGY INTENSITY

Our energy use per capita was level and has been dropping in recent years. Our energy intensity or energy use per dollar of GDP, has been decreasing steadily since 1980. However, because of the increasing US population, total energy use of the nation has been roughly constant between 2000 and 2012.

The Hubbert Curve

Hubbert Curve- an approximation of the production rate of a resource over time, a bell shaped curve representing oil use and projecting both when world oil production will reach a maximum and when the world will run out of oil.

A generalized version of The Hubbert Curve. Whether and upper estimate or lower estimate of total petroleum reserves is used, the date by which petroleum reserves will be depleted does not change substantially.

The Future of Fossil Fuel Use

• If current global use continues without significant additional discovery, we may run out of conventional oil in less than 50 years.

• Coal supplies will last for at least 200 years, and probably much longer.

• New technology and concern about the release of greenhouse gases is encouraging people to explore alternative energy sources.

MODULE 36 YAYYYYYYY

Nuclear reactors use fission to generate electricity

• Electricity generation from nuclear fuel uses uranium-235 as a fuel source.

Fission- a nuclear reaction in which a neutron strikes a relatively large atomic nucleus, which then splits into two or more parts releasing additional neutrons and energy in the form of heat.

A nuclear power plant uses heat from nuclear fission in order to boil water. This water produces steam to turn the turbine which turns a generator.

Nuclear Fission

Nuclear Fission:

Energy is released when a neutron strikes a large atomic nucleus, which then splits into two or more parts.

Fuel rod- A cylindrical tube that encloses nuclear fuel within a nuclear reactor.

Control rod- A cylindrical device inserted between the fuel rods in a nuclear reactor to absorb excess neutrons and slow or stop the fission reaction.

Nuclear energy has both advantages and disadvantages

Advantages:

1. No air pollution

2. Reduces need to import oil

Disadvantages:

1. Possibility of accidents

2. Difficult to dispose of waste

3. Concern about nuclear material being misused

Radioactive waste- Nuclear fuel that can no longer produce enough heat to be useful in a power plant but continues to emit radioactivity.

Becuquerel (Bq)- unit that measures the rate at which a sample of radioactive material decays; 1 Bq = decay of 1 atom or nucleus per second.

Curie- A unit of measure for radiation; 1 Curie equal 37 billion decays per second.

Radioactive Waste

• High-level radioactive waste comes from used fuel rods

• Low-level radioactive waste is found on the protective clothing, tools, and other items used in routine plant maintenance.

• Uranium mine tailings are the residue left after uranium ore is mined and enriched.

• in each case, disposal must be handled with great care.

Fusion Power

Nuclear Fusion- A reaction when lighter nuclei are forced together to produce heavier nuclei.

Nuclear fusion powers the sun and other stars

Fusion is a promising, unlimited source of energy in the future, but so far scientists have had difficulty containing the heat that is produced.

CHAPTER 13 MODULE 37

Thermodynamics: The study of the relations between heat, work, temperature, and energy.

The laws of thermodynamics describe how the energy in a system changes and whether the system can perform useful work on its surroundings.

We can use less energy through conservation and increased efficiency

• Energy conservation and energy efficiency are the least expensive and most environmentally sound options for maximizing our energy resources.

• Energy conservation- Finding and implementing ways to use less energy.

• Tiered rate system- A billing system used by some electric companies in which customers pay higher rates as their use goes up.

• Peak demand- The greatest quantity of energy used at any one time.

Sustainable Design

Sustainable design improves the efficiency of the buildings and communities in which we we live and work.

An energy-efficient home. A sustainable building design incorporates proper solar orientation and landscaping as well as insulated windows, walls, and floors. In the Northern Hemisphere, a southern exposure allows the house to receive more direct rays from the Sun in winter when the path of theSun is in the southern sky.

• Passive solar design- Construction designed to take advantage of solar radiation without active technology.

• Thermal mass- A property of a building material that allows it to maintain heat or cold.

• Using passive solar energy can lower your electricity bill without the need for pumps or other mechanical devices.

• Building the house with windows along a south-facing wall which allows the Sun’s rays to warm the house is an example of passive solar design.

Passive solar design. Passive solar design uses solar radiation to maintain indoor temperature. Roof overhangs make use of seasonal changes in the Sun’s position to reduce energy demand for heating and cooling. In winter, when the Sun is low in the sky, it shines directly into the window and heats the house. In summer, when the Sun is higher in the sky, the overhang blocks incoming sunlight and the room stays cool. High-efficiency windows and building materials with high thermal inertia are also components of passive solar design.

Renewable energy is either potentially renewable or nondepletable

• Potentially renewable- An energy source that can be regenerated indefinitely as long as it is not overharvested.

• Nondepletable- An energy source that cannot be used up.

• Renewable- In energy management, an energy source that is either potentially renewable or nondepletable.

Global energy use. Renewable energy resources provide about 13 percent of energy worldwide.

Energy Use in the United States. Only 7 percent of the energy used in the United States comes from renewable energy resources.

MODULE 38 YAYAYAYAYA

Biomass is energy from the Sun Energy from the Sun. The Sun is the ultimate source of almost all types of energy.

How are fossil fuels related to the sun?

How are “other” fuels related to the sun?

Modern Carbon Versus Fossil Carbon

• Biofuel- Liquid fuel created from processed or refined biomass.

• Modern carbon- Carbon in biomass that was recently in the atmosphere.

• Fossil carbon- Carbon in fossil fuels.

• Carbon neutral- An activity that does NOT change atmospheric CO2 concentrations.

Solid Biomass: Wood, Charcoal, and Manure (Poop unfortunately)

• Wood, charcoal and manure are used to heat homes throughout the world.

• In the developing world, people often cannot afford fossil fuels or do not have access to them.

• Net removal- The process of removing more than is replaced by growth, typically used when referring to carbon.

Solid Biomass

• Use of wood is unsustainable if forest growth does not keep up with forest use.

• Charcoal is lighter than wood and contains twice as much energy per unit of weight. It also produces less smoke.

• In regions where wood is scarce, people often use dried animal manure as a fuel for indoor heating and cooking. Burning manure indoors creates indoor air pollution.

Biofuels: Ethanol and Biodiesel

• Liquid biofuels (all liquid fuels of natural origin) can be used as a substitute for gasoline and diesel.

• Ethanol- Alcohol made by converting starches and sugars from plant material into alcohol and CO2.

• Biodiesel- A diesel substitute produced by extracting and chemically altering oil from plants.

• Flex-fuel vehicle- A vehicle that runs on either gasoline or a gasoline/ethanol mixture.

The kinetic (motion) energy of water can generate electricity

• Hydroelectricity Electricity generated by the kinetic energy of moving water.

• Worldwide, nearly 20% of all electricity comes from hydroelectric power plants with China the leading producer.

The kinetic energy of water can generate electricity

• Hydroelectricity- Electricity generated by the kinetic energy of moving water.

• Run-of-the-river- Hydroelectricity generation in which water is retained behind a low dam or no dam.

• Water impoundment- The storage of water in a reservoir behind a dam.

• Tidal energy- Energy that comes from the movement of water driven by the gravitational pull of the Moon.

Hydroelectricity

A water impoundment hydroelectric dam. Water impoundment, a common method of hydroelectricity generation, allows for electricity generation on demand. Dam operators control the rate of water flow by opening and closing the gates. This determines the amount of electricity generated. The arrows indicate the path of water flow.

Hydroelectricity and Sustainability

Hydroelectricity has many benefits:

• Hydroelectric projects bring renewable energy to large numbers of rural residents worldwide.

• Hydroelectricity does not create air pollution, waste products, or CO2 emissions.

• Electricity generated from hydroelectricity is less expensive.

• Reservoirs create recreational opportunities.

Hydroelectricity has some negative environmental consequences:

• Creating the reservoir may flood agricultural land or places of archeological significance, and force people to relocate.

• Impounding a river can interfere with organisms that depend on a free-flowing river.

• Downstream ecosystems are affected.

• Siltation- The accumulation of sediments, primarily silt, on the bottom of a reservoir.

MODULE 39

The energy of the Sun can be captured directly

Geographic variation in solar radiation in the United States. This map shows the amount of solar energy available to a flat photovoltaic solar panel in kilowatt-hours per square meter per day, averaged over a year.

Passive solar energy- Harnesses the sun's heat through a building's design, like big windows facing the sun, to naturally warm up spaces without using any extra energy. It's like letting sunlight do the work of keeping a place warm and cozy.

Active Solar Energy

Active solar energy Energy captured from sunlight with advanced technologies. Technologies that employ active solar energy include:

• Solar water heating systems

• Photovoltaic systems

• Photovoltaic solar cell A system of capturing energy from sunlight and converting it directly into electricity.

• Large-scale concentrating solar thermal systems for electricity generation (CST)

Benefits of Active Solar Energy Systems

Active solar energy systems offer many benefits:

• Generating hot water or electricity without producing CO2 or polluting the air or water during operation.

• Producing electricity on hot, sunny days when demand for electricity is high.

• Producing electricity during peak demand hours helps reduce the need to build new fossil fuel power plants.

• A photovoltaic system may be less expensive than running electrical transmission lines to some home sites.

Drawbacks of Active Solar Energy Systems

Drawbacks have inhibited the growth of solar energy use in the United States:

• Photovoltaic solar panels are expensive to manufacture and install.

• Manufacturing requires energy and water, and involves a variety of toxic metals and industrial chemicals.

• There are environmental costs associated with the batteries for systems that use batteries for energy storage.

• The end-of-life reclamation and recycling is another potential source of environmental contamination.

Wind energy is the most rapidly growing source of electricity

• Wind energy Energy generated from the kinetic (moving) energy of moving air.

• Wind energy is the fastest growing major source of electricity in the world.

• Ultimately the sun is the source of all winds!

Wind Energy

Installed wind energy capacity by country.

(a) China generates more electricity from wind energy than any other country.

(b) However, some relatively small countries, such as Denmark, generate a much higher percentage of their electricity from wind.

Generating Electricity from Wind

• Wind turbine- A turbine that converts wind energy into electricity.

• The blades of the wind turbine transfer energy to the gear box that transfers energy to the generator.

• Wind turbines on land are typically installed in rural locations, away from buildings and population centers.

• Turbines are typically grouped into wind farms or wind parks.

Generating electricity with a wind turbine. The wind turns the blade, which is connected to the generator, which generates electricity.

The number of wind farms in the U.S. and and around the world is increasing, it is the fastest growing renewable source of energy.

Advantages of wind energy include:

• It is a nondepletable and free energy resource.

• After manufacturing and installation, little energy input other than wind is required.

• Wind-generated electricity produces no pollution and no greenhouse gases.

• Wind farms can share the land with other uses

Disadvantages of wind energy include:

• Most off-grid residential wind energy systems rely on batteries to store.

• Wind turbines can be noisy and unattractive.

• As many as 40,000 birds are killed by wind turbine blades in the United States each year.

• Bats are also killed by wind turbines.

Earth’s internal heat is a source of nondepletable energy

Geothermal energy Heat energy that comes from the natural radioactive decay of elements deep within Earth.

• Geothermal energy can be used directly as a source of heat.

• Many countries obtain clean, renewable energy from geothermal resources.

• The United States, China, and Iceland, all of which have substantial geothermal resources, are the largest geothermal energy producers. Overall however it has the less potential for growth than solar or wind because it is not easily accessible everywhere and hazardous gases could potentially escape from power plants.

Ground Source Heat Pumps

• Ground source heat pump- A technology that transfers heat from the ground to a building.

• Although the heat tapped by ground source heat pumps is often informally referred to as “geothermal,” it comes from solar energy.

Hydrogen fuel cells have many potential applications

• Fuel cell- An electrical-chemical device that converts fuel, such as hydrogen, into an electrical current.

• Electrolysis- The application of an electric current to water molecules to split them into hydrogen and oxygen.

Power from a hydrogen fuel cell.

(a) Hydrogen gas enters the cell from an external source. Protons from the hydrogen molecules pass through a membrane, while electrons flow around it, producing an electric current. Water is the only waste product of the reaction.

(b) In a fuel cell vehicle, hydrogen is the fuel that reacts with oxygen to provide electricity to run the motor.

MODULE 40

Our energy future depends on efficiency, conservation, and the development of renewable and nonrenewable energy resources.

No single energy can replace nonrenewable energy resources in a way that is completely renewable, nonpolluting, and free of impacts on the environment. A sustainable energy strategy must combine:

• Energy efficiency

• Energy conservation

• Development of renewable and nonrenewable energy resources

A sustainable energy strategy must consider the costs, benefits, and limitations of each energy source.

• Convenience, reliability, and logistical considerations are also important.

• Smart grid- An efficient, self-regulating electricity distribution network that accepts any source of electricity and distributes it automatically to end users.

Renewable energy strategy presents many challenges

• Renewable energy sources will not likely replace fossil fuels in the near future unless: tax incentives are put in place, consumer rebates, direct funding and other financial incentives.

• Government funding and other sources of capital are needed to support research to overcome the current limitations of many renewable energy sources.

Using a smart grid. So in addition to investing in new energy sources, the U.S. will have to upgrade its existing electrical infrastructure- its power plants, storage capacity, and distribution networks.

Using a smart grid. A smart grid optimizes the use of energy in a home by continuously coordinating energy use with energy availability

Smart Grid

• Improving the electrical grid can make moving electricity from place to place more efficient, thereby reducing the need for storage capacity.

• A smart grid uses computer programs and the internet to move energy around thereby distributing the energy more evenly during peak times and low times.

• Some experts argue for increase the number of power plants and decrease there size. In other words, have lots of small power plants with a mixture of energy sources.

DEFINITIONS:

Smart Grid:

A smart grid is an advanced electrical grid system that uses digital technology to efficiently manage electricity generation, distribution, and consumption. It integrates renewable energy sources, enhances reliability, and allows for two-way communication between consumers and utility providers for optimized energy usage.

Nuclear Fusion:

Nuclear fusion is like when two smaller atoms join together to make a bigger one, releasing a lot of energy in the process. It's what powers the sun and stars, and scientists are trying to recreate it on Earth as a super clean and powerful energy source.

Radioactive waste:

Leftover material from nuclear reactors that can't produce enough heat for power but still emits radiation. It needs careful handling due to its potential hazards.

Becquerel (Bq):

A unit measuring how fast radioactive material breaks down. One Bq equals one atom or nucleus decaying per second. It helps gauge the level of radioactivity in a substance.

Curie:

Another unit for measuring radiation. One Curie is a lot of decay—specifically, 37 billion atoms or nuclei breaking down per second. It's a way to describe larger amounts of radioactivity.

Fission:

Fission is like breaking a big atom into smaller pieces. When you split an atom, it releases a bunch of energy in the form of heat and radiation. This process is what powers nuclear reactors to generate electricity. It's kind of like breaking a big block of chocolate into smaller chunks and getting energy from it.

Hubbert Curve:

The Hubbert curve, named after geologist M. King Hubbert, is a simple graph that shows how the production of a non-renewable resource, like oil, is expected to increase and then eventually decline over time. It's shaped like a bell curve, with production ramping up as more of the resource is extracted, reaching a peak, and then gradually declining as the resource becomes harder to find and extract. This curve helps predict when a resource's production will reach its maximum point, known as "peak production," and when it will start to decline.

Oil Sands:

Oil sands are mixtures of sand, water, clay, and bitumen, a thick, heavy form of petroleum.

Nondepleatable:

"Nondepletable" refers to resources or energy sources that cannot be exhausted or used up, either because they are naturally replenished at a rate equal to or greater than the rate at which they are consumed, or because they are infinite in supply. Examples include solar energy, wind energy, and tidal energy, which are constantly renewed by natural processes and are not diminished by human use.

Passive Solar Energy:

Passive solar energy harnesses the sun's heat through a building's design, like big windows facing the sun, to naturally warm up spaces without using any extra energy. It's like letting sunlight do the work of keeping a place warm and cozy.