envs 101 exam 3 study guide

COAL – Source & Origin

Coal forms from ancient vegetation compressed under heat/pressure for millions of years between rock strata; abundant in US, Russia, China, Australia, India.

COAL – Production

Mined, pulverized (PCC), burned to heat water into steam → steam spins turbine generators → electricity at ~32–33% efficiency.

COAL – Technology

PCC combustion, generators, turbines, large-scale power plants.

COAL – Advantages

Cheap, abundant, long-lasting reserves; supports global energy needs; provides 500,000+ jobs; accessible and affordable.

COAL – Sustainability Notes

Higher-grade coals (bituminous/anthracite) release fewer pollutants than lignite but still harmful.

COAL – Innovations

CCS, HELE plants, coal gasification, syngas systems, rising efficiency.

COAL – Disadvantages

Major land disruption; water pollution; air pollution; GHG emissions; toxic coal dust; risks of explosions; acid drainage; severe community health impacts.

COAL – Justice Issues

Low-income & rural communities disproportionately affected by pollution.

COAL – Future Trends

Syngas technology, efficiency increases, challenges due to cost & maintenance; AI/data-center energy demand may increase coal use.

OIL – Source & Origin

Formed from marine organisms under heat/pressure; top producers US, Saudi Arabia, Russia, Canada, Iraq.

OIL – Extraction & Refining

Pump jacks, drilling rigs, offshore wells; refined through separation, conversion, treatment.

OIL – Uses

Transportation fuels, heating oil, plastics, asphalt, fertilizers, petrochemicals.

OIL – Advantages

High energy density; reliable; global infrastructure; millions of jobs; trillions in tax revenue.

OIL – Innovations

Digital oilfields, EOR, robotics, seismic imaging, improved recycling of used oil.

OIL – Disadvantages

Spills, habitat loss, CO2 emissions, air pollution, human health risks, worker hazards.

OIL – Justice Issues

Low-income & frontline communities near refineries suffer increased pollution; developing nations dependent on oil.

OIL – Controversies

Deepwater disasters, greenwashing, global geopolitical tensions.

NATURAL GAS – Source & Origin

Non-renewable, formed deep below earth's surface over millions of years by compression, heat, and pressure on ancient organisms/plankton remains.

NATURAL GAS – Production

Mainly through drilling (on land and offshore rigs) after seismic scans locate pockets. Also extracted via fracking (shale gas).

NATURAL GAS – Technology

Gas burned in combustion turbine/boiler to create high-pressure gases → power turbine blades → mechanical energy to electric generator.

NATURAL GAS – Extraction Methods

Conventional gas fields, shale gas (fracking), tight gas (limestone/minerals), biogenic gas.

NATURAL GAS – Advantages

Globally abundant resource (estimated 50-100 years left). Creates many job opportunities (3.4 million in 2018). Cleaner than coal/oil; acts as a bridge to emission-free world. High energy efficiency. Used for heating, cooking, plastics, fertilizers.

NATURAL GAS – Disadvantages

Nonrenewable. Leaks methane (a significantly more harmful GHG than CO2) into atmosphere, contributing to large-scale emissions over time. Fracking destroys habitats, contaminates air/water, and can cause earthquakes. Proprietary rights can lead to underreporting of environmental impact.

NATURAL GAS – Future Trends/Innovations

RNG (renewable natural gas) from organic waste/landfills. Hydrogen blending (combines natural gas and hydrogen). Carbon capture and storage on natural gas emissions. Transported via LNG (liquefied natural gas).

HYDROPOWER – Source

Renewable energy from flowing water replenished by hydrologic cycle.

HYDROPOWER – Technology

Dams, run-of-river systems; turbines convert kinetic → mechanical → electrical energy; up to 90% efficiency.

HYDROPOWER – Advantages

Low operating costs; reliable; low emissions; grid stability; supports drought/flood control; pumped-storage acts as a battery.

HYDROPOWER – Social Benefits

Supports recreation, fisheries, employs engineers & maintenance staff.

HYDROPOWER – Disadvantages

Displacement, habitat loss, fish migration harm, methane emissions from reservoirs, landslides, drought risk, sediment buildup.

HYDROPOWER – Justice Issues

Indigenous displacement; unfair compensation; rural communities bear the burden.

HYDROPOWER – Trends

Modernization, eco-friendly turbines, pumped storage expansion, dam removal for ecosystem restoration.

WIND – Source

Wind formed by uneven solar heating; best regions Great Plains, Appalachians, western US.

WIND – Production

Turbine blades spin rotor → generator → electricity; wind farms.

WIND – Advantages

No fuel; no mining/drilling; zero emissions; domestic energy; 20–25:1 EROI; 90% cost drop in 25 years; fast-growing energy source.

WIND – Social Benefits

Local jobs; landowner income; rural development; quick energy payback (6–8 months).

WIND – Disadvantages

Bird/bat deaths; materials require fossil fuels; nonrecyclable blades; NIMBY issues; intermittency; visual/noise concerns.

WIND – Justice Issues

Land conflicts with Indigenous communities (e.g., Sámi herding lands).

WIND – Trends

Offshore growth, taller turbines, smart grids, cheaper installation, storage pairing.

BIOMASS – Source

Renewable from plants, wood, waste; ~5% of US energy.

BIOMASS – Production

Harvesting, collecting crops/waste; combustion, anaerobic digestion, fermentation (ethanol), gasification, pyrolysis.

BIOMASS – Advantages

Supports rural jobs; renewable on human timescale; reduces waste; improves carbon cycle; reduces fossil fuel imports.

BIOMASS – Disadvantages

Not carbon neutral; deforestation; fertilizer/pesticide pollution; food price increases; low net efficiency; inequality between rich & poor nations.

BIOMASS – Justice Issues

Deforestation & food insecurity in poorer regions while wealthier nations benefit.

BIOMASS – Key Takeaway

Useful but limited; not truly carbon neutral; uneven global impacts.

SOLAR – Source

Energy from sunlight; passive and active systems; used for electricity, heating, lighting.

SOLAR – Technology

PV panels, CSP mirrors, floating solar, bifacial panels, solar thermal systems.

SOLAR – Advantages

Renewable; clean; scalable; job creation; declining costs; long lifespan; no fuel.

SOLAR – Disadvantages

High upfront cost; hazardous materials; panel disposal issues; mining impacts; labor issues.

SOLAR – Justice Issues

Forced labor concerns in polysilicon supply chain; land-use conflicts.

SOLAR – Innovations

Floating solar, bifacial panels, improved CSP, solar thermal storage.

NUCLEAR – Source

Fission of uranium releases heat; used for electricity.

NUCLEAR – Technology

Reactor → heat → steam → turbine → generator; cooling tower recycles water; 66% efficiency.

NUCLEAR – Advantages

Large-scale clean energy; supports millions of homes; reduces fossil fuel use; high job creation; stable baseload.

NUCLEAR – Disadvantages

Toxic, long-lasting waste; mining dangers; disasters (Chernobyl/Fukushima); expensive; radiation health risks.

NUCLEAR – Justice Issues

Communities near waste storage face exposure; inequitable global access to safe tech.

NUCLEAR – Exam Notes

Know fission vs fusion; environmental impacts; nuclear’s clean energy role.

Energy Transition - Why transition away from fossil fuels

They drive climate change; limited supply; harmful externalities

Energy Transition - Why electrify everything

Electricity can be clean; higher efficiency; reduces fossil dependence

Energy Transition - Why nuclear is needed

Provides stable, zero-carbon baseload power during transition

Climate Change 1 - Methods to know past climate

Ice cores, sediment cores, tree rings, fossils

Climate Change 1 - Evidence of rapid climate change

Glacier melt, sea level rise, CO₂ increase, temp rise, ocean warming, extreme weather, species shifts, ice sheet loss, acidification

Climate Change 1 - Five greenhouse gases

CO₂, methane, nitrous oxide, fluorinated gases, water vapor

Climate Change 2 - GWP Definition

How strongly a gas warms the planet relative to CO₂

Climate Change 2 - Mitigation vs Adaptation

Mitigation = reduce emissions; adaptation = adjust to impacts

Climate Change 2 - Why time matters for mitigation

The longer we wait, the more warming becomes locked in

Climate Change 2 - Project Drawdown Top solutions

Renewables, efficiency, food waste reduction, plant-rich diets, refrigerant management, reforestation, etc.

Climate Change 3 - Countries emitting most today

China, U.S., India

Climate Change 3 - Highest historical emissions

U.S., EU, China

Climate Change 3 - Highest per-person emissions

U.S., Australia, oil-rich Gulf states

Climate Change 3 - CO₂ in 2021 vs past

Record high; higher than recent years and decades

Climate Change 3 - Wealth–emissions connection

Rich countries emit far more per capita

Climate Change 3 - What developed countries can do

Fund renewables, transfer tech, reduce own emissions

Climate Change 4 - Emissions vs poverty concern

Policies must not hinder development in poorer nations

Climate Change 4 - Food/meat emissions

Agriculture major GHG source; beef especially high impact

Climate Change 4 - Problems with individual-blame narrative

Shifts attention from systemic + corporate emitters

Climate Change 4 - Two main individual actions

Vote for climate policy + change food/consumption patterns