Midterm Study Guide: Energy and the Environment

Forms of energy-Potential energies, chemical, kinetic, etc.

• Potential Energy: Energy stored in an object due to its position or condition (e.g., a stretched rubber band).

• Kinetic Energy: Energy of motion; any object in motion has kinetic energy (e.g., a moving car).

• Chemical Energy: Energy stored in the bonds of chemical compounds, released during chemical reactions (e.g., in food or batteries).

• Thermal Energy: Energy due to the temperature of an object; related to the movement of particles within it (e.g., heat).

• Electrical Energy: Energy from the movement of electric charges (e.g., power in a circuit).

• Nuclear Energy: Energy stored in the nucleus of atoms, released in nuclear reactions (e.g., nuclear power plants).

• Gravitational Potential Energy: Energy stored due to an object's height and gravity (e.g., a rock on a hill).

• Elastic Potential Energy: Energy stored when an object is stretched or compressed (e.g., a spring).

Energy conversions

• Transformations from one form of energy to another. Can be converted in many ways, Natural processes: Solar energy evaporates water. 

• Technology: Burning fossil fuels converts chemical energy into electricity.

•  Human actions: Eating an apple converts the chemical energy stored in the apple into mechanical energy when a person moves. 

Energy can take many forms, including:

chemical, atomic, electrical, mechanical, light, potential, pressure, kinetic, and heat. 

Uses for each form of energy-Applications of different energy forms in various contexts.

• Chemical Energy: 

  • Fuel for transportation: Gasoline in cars, diesel in trucks, burning natural gas for heating homes. 

  • Food for living organisms: Energy stored in food that powers our bodies. 

• Electrical Energy: 

  • Powering appliances: Running household appliances like refrigerators, washing machines, lights. 

  • Industrial machinery: Operating large machinery in factories. 

  • Electronics: Charging phones, laptops, and other electronic devices. 

• Thermal Energy (Heat): 

  • Heating homes and buildings: Using furnaces, boilers, or fireplaces to warm spaces 

  • Cooking food: Using stoves, ovens, or microwaves 

  • Industrial processes: Heat used in manufacturing processes like metalworking 

• Mechanical Energy (Motion): 

  • Transportation: Movement of vehicles like cars, trains, and airplanes 

  • Machinery operation: Rotating parts in machinery like turbines and gears 

  • Human movement: Physical activity like walking, running, lifting objects 

• Light Energy: 

  • Illumination: Light bulbs, lamps, streetlights for visibility 

  • Photography: Capturing images using camera sensors 

  • Solar energy: Using sunlight to generate electricity through photovoltaic cells 

• Potential Energy (Stored Energy): 

  • Gravity-based: Water stored in a dam (hydroelectric power), objects lifted above the ground 

  • Elastic potential: Energy stored in a stretched rubber band 

Watt & Basic scale of energy use

A "watt" is the basic unit used to measure electrical power, essentially how much energy is being used at a specific moment, / The basic scale of energy use is measured in Joules (J)

What is “heat” and how does it different from “thermal energy” and “temperature”?

Thermal energy is the energy contained in a system. Heat is the flow of thermal energy. Temperature is the average kinetic energy of the molecules.

First law of thermodynamics

Energy cannot be created or destroyed, only transformed.

Second law of thermodynamics

In any energy transfer, there will always be a loss of usable energy.

Entropy

A measure of disorder or randomness in a system.

Radiation

The transfer of energy through space via electromagnetic waves.

Convection

The transfer of heat through the movement of fluids.

Conduction

The transfer of heat through direct contact between materials.

Specific heat

The amount of heat required to raise the temperature of a unit mass of a substance by one degree Celsius.

General efficiencies of power plants, internal combustion engines – why are they so inefficient?

a large portion of the energy stored in their fuel is lost as heat during the combustion process

 How do chemical bonds store energy?

by holding atoms together in a stable arrangement, with the potential energy stored within the attractive forces between the atoms

Biomass vs. fossil fuels  compare/contrast, current uses of each

=Biomass:

- Source: Organic material (plants, waste)

- Renewable: Yes (can regrow or reuse waste)

- Carbon Impact: Can be carbon-neutral

- Energy Density: Lower

Fossil Fuels:

- Source: Ancient plants/animals (coal, oil, gas)

- Renewable: No (takes millions of years to form)

- Carbon Impact: High CO2 emissions

- Energy Density: Higher

Formation of coal

when dead plant matter is subjected to heat and pressure over millions of years

Stages of coal formation

peat, lignite, bituminous coal, and anthracite; with each stage representing an increase in pressure and heat, resulting in a higher carbon content and harder coal rank

Resource vs. reserve

A resource is a naturally occurring substance, while a reserve is a known deposit that can be economically extracted.

Environmental and human impacts of coal (all 5 stages)

The environmental and human impacts of coal occur throughout its lifecycle, from mining to combustion, including significant air and water pollution, land disruption, and public health risks, mainly due to the release of greenhouse gases like carbon dioxide, sulfur dioxide, nitrogen oxides, particulate matter, and heavy metals like mercury, impacting ecosystems and human health at every stage:. 

1. Coal Mining: 

• Land disruption:

  Surface mining, particularly mountaintop removal, drastically alters landscapes, destroying forests and burying streams, leading to habitat loss and ecosystem disruption. 

• Water pollution:

  Acid mine drainage, where acidic water containing heavy metals like iron, arsenic, and lead contaminates nearby waterways, affecting aquatic life and drinking water sources. 

• Worker safety:

  Risks of mine collapses, gas explosions, and injuries associated with underground mining. 

2. Coal Processing: 

• Water pollution:

  Waste from coal preparation plants, containing coal sludge and chemicals, can contaminate water bodies if not properly managed. 

• Air pollution:

  Dust emissions during coal handling and processing can impact local air quality. 

3. Coal Transportation: 

• Air pollution: Dust from coal transport by rail or truck contributes to local air pollution, particularly in densely populated areas. 

• Spills and leaks: Accidental spills during transport can contaminate soil and water sources. 

4. Coal Combustion (Power Plants): 

• Greenhouse gas emissions:

  Burning coal is a major source of carbon dioxide, contributing significantly to climate change. 

• Air pollution:

  Emissions of sulfur dioxide, nitrogen oxides, particulate matter, and heavy metals like mercury, leading to respiratory problems, acid rain, and smog. 

• Impact on human health:

  Increased risk of respiratory illnesses, cardiovascular diseases, and cancer due to air pollution exposure. 

5. Coal Waste Disposal: 

• Coal ash disposal: Fly ash and bottom ash from coal burning can contaminate water sources if not properly managed, leading to heavy metal pollution. 

• Landfill contamination: Coal ash disposal sites can leach pollutants into groundwater. 

Formation of petroleum and where we find it

Benefits of petroleum

provides transportation, heat, light, and plastics to global consumers

Basic refining process

The procedure used to convert crude oil into usable products.

Salt domes-formation and oil drilling in Gulf of Mexico

Geological formations that can trap oil and gas, particularly in the Gulf of Mexico.

Natural gas/shale gas as a bridge fuel (arguments for and against)

For:

• Lower Emissions: Emits less CO2 than coal or oil when burned.

• Energy Transition: Can help shift from coal to cleaner energy sources.

• Abundant: Widely available and provides reliable power.

Against:

• Methane Leaks: Methane (a potent greenhouse gas) can leak during extraction and transport.

• Delayed Renewable Adoption: Investment in gas may slow the shift to renewables.

• Fracking: Extracting shale gas can harm water supplies and cause earthquakes.

Keeling Curve

A graph that shows the increase of carbon dioxide in the atmosphere over time.

Greenhouse effect  greenhouse gases

The warming of Earth's surface due to the trapping of heat by greenhouse gases.

Café standards

Regulations aimed at improving the average fuel economy of cars and trucks.

Tropospheric ozone/photochemical smog

Tropospheric Ozone:

• What it is: Ozone (O₃) formed at ground level, harmful to breathe.

  Cause: Created by chemical reactions between pollutants (like vehicle emissions) and sunlight.

• Impact: Causes respiratory problems and harms plants.

Photochemical Smog:

• What it is: A type of air pollution, made up of ozone and other chemicals.

• Cause: Forms in cities with lots of sunlight, vehicle exhaust, and industrial emissions.

• Impact: Reduces air quality, visibility, and affects health (asthma, lung damage).

 Tradeoffs of nuclear energy (arguments for and against)

For:

• Low Emissions: Produces almost no greenhouse gases.

• Reliable: Provides constant, large-scale power.

• Efficient: High energy output from small fuel amounts.

Against:

• Radioactive Waste: Long-lasting, difficult to store safely.

• Accidents: Risk of disasters (e.g., Chernobyl, Fukushima).

• High Cost: Expensive to build and maintain plants.

Fusion vs. fission

Two different nuclear reactions used to release energy. Fusion:

• Process: Combines two light atomic nuclei (like hydrogen) to form a heavier nucleus.

• Energy: Produces more energy than fission.

• Waste: Less radioactive waste, but hard to achieve controlled fusion.

• Example: Powers the sun.

Fission:

• Process: Splits a heavy atomic nucleus (like uranium) into smaller nuclei.

• Energy: Produces less energy than fusion but is currently easier to control.

• Waste: Generates more radioactive waste.

• Example: Used in nuclear power plants today.

Major nuclear accidents (3 Mile Island, Chernobyl, Fukushima)

Three Mile Island (1979, USA):

• Cause: Reactor meltdown due to equipment failure and human error.

• Impact: Small release of radiation, no immediate deaths, but raised safety concerns.

Chernobyl (1986, Ukraine):

• Cause: Reactor explosion during a test gone wrong.

• Impact: Massive radiation release, 30 immediate deaths, long-term health issues, widespread contamination.

Fukushima (2011, Japan):

• Cause: Earthquake and tsunami led to reactor meltdowns.

• Impact: Radiation release, evacuations, long-term environmental damage, no immediate deaths from radiation.

4o

Why is biomass an inefficient source of energy? (there are many reasons...)

• Low Energy Density: Biomass contains less energy per unit compared to fossil fuels.

• Land Use: Requires large areas of land for growing crops, which could be used for food production.

• Processing and Transport: Biomass is bulky and expensive to collect, transport, and process.

• Variable Quality: Energy output depends on the type and condition of biomass (e.g., moisture content).

• Carbon Emissions: Not always carbon-neutral due to emissions from harvesting, processing, and burning.

• Seasonal Availability: Biomass availability can fluctuate based on seasons and climate conditions.

Energy density of fuels – why does this matter?

 Advantages of fossil fuels (coal, petroleum)

Coal:

• Abundant: Widely available and found in many countries.

• Low Cost: Generally cheaper to extract and use compared to other energy sources.

• Reliable: Provides a stable and consistent power supply.

• High Energy Content: Produces a large amount of energy per unit when burned.

Petroleum:

• Versatile: Can be refined into various products (gasoline, diesel, jet fuel, plastics).

• High Energy Density: Offers more energy per volume than many other fuels.

• Established Infrastructure: Extensive systems for extraction, refining, and distribution.

• Economic Driver: Significant contributor to jobs and economic growth in many regions.

 General locations of oil resources/reserves

• Middle East:

  • Major reserves in countries like Saudi Arabia, Iraq, and Iran.

• North America:

  • Significant reserves in the United States (Texas, Alaska) and Canada (Alberta's oil sands).

• South America:

  • Notable reserves in Venezuela and Brazil.

• Africa:

  • Major oil-producing countries include Nigeria and Angola.

• Asia:

  • Reserves in Russia and Kazakhstan; smaller amounts in countries like Indonesia and Malaysia.

• Europe:

  • Limited reserves; notable production in the North Sea (UK and Norway).

• Energy policy vs. environmental policy

Energy Policy:

• Focus: Addresses the production, distribution, and consumption of energy.

• Goals: Ensures energy security, affordability, and reliable supply.

• Considerations: Emphasizes energy sources (renewable vs. non-renewable) and technologies (electricity, transportation fuels).

Environmental Policy:

• Focus: Aims to protect the environment and public health.

• Goals: Reduces pollution, conserves natural resources, and protects ecosystems.

• Considerations: Addresses issues like climate change, biodiversity, and waste management, often influencing energy choices.

Combustion of fossil fuels – natural gas vs. petroleum vs. coal in terms of emissions

• Emissions:

  • Produces the least CO2 per energy unit (about 50-60% less than coal).

  • Emits very low levels of sulfur dioxide (SO₂) and particulate matter.

  • Can release methane during extraction and transport, which is a potent greenhouse gas.

Petroleum:

• Emissions:

  • Moderate CO2 emissions, higher than natural gas but lower than coal.

  • Emits significant amounts of carbon monoxide (CO) and volatile organic compounds (VOCs).

  • Produces SO₂, nitrogen oxides (NOx), and particulates, contributing to air pollution.

Coal:

• Emissions:

  • Highest CO2 emissions per unit of energy.

  • Produces substantial SO₂, NOx, and particulate matter, leading to severe air quality issues.

  • Associated with higher levels of heavy metals and other harmful pollutants.

Environmental and social impacts of natural gas use

Environmental Impacts:

• Methane Emissions: Leakage during extraction and transport contributes to greenhouse gas emissions, which are more potent than CO2.

• Water Use: Hydraulic fracturing (fracking) requires significant water resources, affecting local water availability.

• Contamination Risks: Potential for groundwater contamination from fracking fluids and produced water.

• Habitat Disruption: Drilling and infrastructure development can lead to habitat loss and fragmentation for wildlife.

• Air Quality: Combustion emits nitrogen oxides (NOx), which can contribute to smog formation and respiratory issues.

Social Impacts:

• Economic Benefits: Job creation in extraction, transportation, and processing sectors; local economic growth.

• Community Concerns: Residents near drilling sites may experience health issues and lower property values.

• Infrastructure Strain: Increased demand for services and infrastructure (roads, water, etc.) can strain local communities.

• Indigenous Rights: Development may infringe on the rights and lands of Indigenous peoples, leading to conflicts and social tensions.

Carbon dioxide – properties, production during combustion, correlation between atmospheric CO2 and temperature

Properties:

• Chemical Formula: CO₂ (one carbon atom and two oxygen atoms).

• State: Colorless, odorless gas at room temperature.

• Density: Heavier than air, leading to accumulation in low-lying areas.

• Solubility: Dissolves in water to form carbonic acid, contributing to ocean acidity.

Production During Combustion:

• Fossil Fuels: Produced when hydrocarbons (coal, oil, natural gas) are burned for energy.

• Biomass: Emitted during the combustion of organic materials (wood, agricultural waste).

• Chemical Reaction: Combustion of carbon-based fuels typically follows the reaction: C+O2→CO2+Energy\text{C} + \text{O}_2 \rightarrow \text{CO}_2 + \text{Energy}C+O2​→CO2​+Energy

Correlation Between Atmospheric CO₂ and Temperature:

• Greenhouse Gas: CO₂ traps heat in the atmosphere, contributing to the greenhouse effect.

• Historical Data: Ice core samples show that increased CO₂ levels correlate with higher global temperatures over geological timescales.

• Current Trends: Rising atmospheric CO₂ concentrations, largely due to human activities (fossil fuel combustion, deforestation), are linked to observed global warming and climate change.

Impacts of climate change

Environmental Impacts:

• Rising Temperatures: Increased average global temperatures lead to heatwaves and altered ecosystems.

• Melting Ice and Rising Sea Levels: Polar ice caps and glaciers are melting, causing sea levels to rise, threatening coastal communities.

• Extreme Weather Events: More frequent and severe storms, floods, droughts, and wildfires.

• Ocean Acidification: Increased CO₂ absorption leads to acidified oceans, harming marine life, particularly coral reefs and shellfish.

• Biodiversity Loss: Species face extinction due to habitat loss, changing climates, and disrupted ecosystems.

Social Impacts:

• Food Security: Changes in temperature and precipitation patterns affect crop yields and food production.

• Health Risks: Increased respiratory issues, heat-related illnesses, and spread of diseases due to changing climate conditions.

• Water Scarcity: Altered rainfall patterns lead to droughts and reduced freshwater availability.

• Economic Consequences: Damage to infrastructure, increased insurance costs, and loss of productivity due to climate-related events.

• Displacement and Migration: Communities may be forced to relocate due to rising sea levels and extreme weather, leading to climate refugees.

 Benefits of electricity as a vehicle for energy

• Efficiency: Electric vehicles (EVs) convert a higher percentage of energy from the grid to power at the wheels compared to internal combustion engines.

• Low Emissions: EVs produce zero tailpipe emissions, reducing air pollution and greenhouse gas emissions, especially when charged with renewable energy sources.

• Renewable Integration: Can be powered by renewable energy sources (solar, wind, hydro), promoting sustainability and reducing dependence on fossil fuels.

• Lower Operating Costs: Electricity is generally cheaper than gasoline or diesel, leading to lower fuel costs for EV owners.

• Reduced Noise Pollution: Electric motors operate more quietly than combustion engines, contributing to lower noise levels in urban areas.

• Technological Advancements: Continued innovations in battery technology are improving range, charging speed, and efficiency, making electric vehicles more viable.

• Energy Independence: Reduces reliance on imported oil, enhancing national energy security and stability.

Generation of electricity (know the basics of how this works)

Energy Sources:

• Fossil Fuels: Coal, natural gas, and oil are burned to heat water, producing steam.

• Nuclear Power: Nuclear reactions generate heat, also used to produce steam.

• Renewable Sources: Solar panels convert sunlight directly into electricity, wind turbines harness wind energy, and hydroelectric plants use flowing water to turn turbines.

2. Conversion to Mechanical Energy:

• In thermal power plants (coal, gas, nuclear), steam generated from heated water spins turbines.

• In wind and hydroelectric plants, wind or water flow turns turbines directly.

3. Electromagnetic Induction:

• Turbines are connected to generators. As turbines spin, they rotate a magnet within coils of wire or vice versa.

• This movement induces an electric current through electromagnetic induction, generating electricity.

4. Transmission:

• The generated electricity is sent through transformers to increase voltage for efficient transmission over power lines to homes and businesses.

5. Distribution:

• Once electricity reaches substations, the voltage is reduced and distributed to consumers for use in homes, industries, and businesses.

Energy portfolios – why do states/countries use particular resources for electricity Generation?

• Resource Availability:

  • Local Resources: States or countries utilize resources that are readily available, such as coal, natural gas, hydro, wind, or solar.

  • Geographic Factors: Topography, climate, and natural resources influence the feasibility of certain energy sources (e.g., sunny areas for solar, windy areas for wind energy).

• Economic Considerations:

  • Cost of Production: The economic viability of energy sources affects decisions; cheaper resources tend to be prioritized.

  • Job Creation: Developing local energy industries can create jobs and stimulate economic growth.

• Energy Security:

  • Independence: Countries may choose resources to reduce reliance on imported energy and enhance energy security.

  • Diverse Portfolio: A mix of energy sources can mitigate risks associated with supply disruptions.

• Environmental Impact:

  • Regulations: Compliance with environmental policies and regulations can drive the adoption of cleaner energy sources.

  • Public Pressure: Growing concern over climate change and pollution encourages shifts towards renewable energy sources.

• Technological Advancements:

  • Innovation: Advances in technology can make previously uneconomical resources more viable (e.g., improved efficiency in solar panels or wind turbines).

  • Investment: States may invest in specific technologies to enhance generation capabilities.

• Infrastructure:

  • Existing Systems: The current energy infrastructure can limit or favor certain energy sources; states with established coal plants may continue using them.

  • Grid Compatibility: Some energy sources are easier to integrate into existing electrical grids.

• Policy and Regulation:

  • Government Incentives: Subsidies or tax incentives for specific energy sources can shape the energy portfolio.

  • Long-term Planning: National or regional energy strategies guide the development and investment in certain technologies.

Challenges to reducing reliance on cars

• Energy Needs of the Transportation Sector: Flashcard

  • Fuel Types: Uses gasoline, diesel, natural gas, and electricity.

  • High Demand: Accounts for about 25% of global energy consumption.

  • Infrastructure: Requires fuel supply networks and charging stations for electric vehicles.

  • Efficiency: Focus on improving vehicle efficiency and developing alternative fuels.

  • Environmental Impact: Major source of greenhouse gas emissions; shifts needed for cleaner energy.

Energy needs of the transportation sector

• Fuel Types:

  • Gasoline & Diesel: Mainly for cars, trucks, and buses.

  • Natural Gas: Used in some public transport and commercial vehicles.

  • Electricity: Powering electric vehicles (EVs) and trains.

• Energy Consumption:

  • Accounts for about 25% of global energy use.

• Infrastructure:

  • Needs fuel supply networks (refineries, gas stations) and charging stations for EVs.

• Efficiency Improvements:

  • Focus on better vehicle designs and public transport options to save energy.

• Environmental Concerns:

  • Significant contributor to greenhouse gas emissions; push for cleaner energy solutions.

Particulate matter

• Definition: Tiny solid or liquid particles suspended in the air, measured in micrometers (PM10 and PM2.5).

• Sources:

  • Natural: Dust, pollen, volcanic ash.

  • Human-made: Vehicle emissions, industrial processes, construction, and burning of fossil fuels.

• Health Effects:

  • Can cause respiratory issues, cardiovascular diseases, and worsen asthma.

  • Fine particles (PM2.5) penetrate deep into the lungs and bloodstream.

• Environmental Impact:

  • Contributes to smog formation and poor air quality.

  • Affects visibility and can harm ecosystems.

• Regulation:

  • Monitored by environmental agencies due to its significant health and environmental risks.

Policy and legislation to address air pollution

• Clean Air Act:

  • U.S. federal law aimed at controlling air pollution; sets national air quality standards.

• Emission Standards:

  • Regulations limiting the amount of pollutants (like NOx, SO₂, and particulate matter) that can be emitted from vehicles and industrial sources.

• Air Quality Monitoring:

  • Requirements for monitoring air quality and reporting data to assess compliance with standards.

• State Implementation Plans:

  • States must develop plans to meet federal air quality standards, tailored to local conditions.

• Incentives for Clean Technology:

  • Financial incentives for businesses and individuals to adopt cleaner technologies (e.g., electric vehicles, renewable energy).

• Public Awareness Campaigns:

  • Programs to educate the public on air pollution and encourage behaviors that reduce emissions (like using public transit).

• International Agreements:

  • Participation in global efforts (e.g., the Paris Agreement) to address transboundary air pollution and climate change.

Radioactivity, human health impacts

• Definition:

  • Radioactivity is the release of energy and particles from unstable atomic nuclei as they decay.

• Sources:

  • Natural: Radon gas, cosmic rays, and certain minerals.

  • Man-made: Nuclear power plants, medical procedures (X-rays, cancer treatments), and nuclear weapons.

• Health Impacts:

  • Acute Effects: High doses can cause radiation sickness, leading to nausea, vomiting, and damage to internal organs.

  • Long-term Effects: Increased risk of cancer (particularly leukemia and thyroid cancer) due to DNA damage from exposure.

  • Genetic Damage: Potential harm to reproductive cells, leading to genetic mutations in future generations.

• Exposure Routes:

  • Inhalation of radioactive particles, ingestion of contaminated food or water, and external exposure from radiation sources.

• Regulations:

  • Guidelines set by organizations (e.g., EPA, WHO) to limit exposure to radiation and protect public health.