Energy Concepts and Consumption

Energy Part I Overview

Global Direct Primary Energy Consumption

  • Energy Measurement

    • Measured in terawatt-hours (TWh)

    • Direct primary energy accounts for losses due to inefficiencies in energy production.

    • Historical energy consumption data spans from 1800 to 2024, highlighting significant trends and usage by year.

    • Total Consumption: 180,000 TWh to 0 TWh between 1800 and 2024.

    • Data Sources: Energy Institute - Statistical Review of World Energy (2025); Smil (2017)

    • Note: Traditional biomass is assumed constant since 2015.

  • Chart Depiction: A graph plots the energy consumption over time, showing various energy sources (modern biofuels, renewables, nuclear, fossil fuels like gas, oil, and coal).

U.S. Primary Energy Consumption by Source (2023)

  • Total Energy Consumption: 93.59 quadrillion British thermal units

  • Energy analysis by source with corresponding percentages:

    • Natural Gas: 36%

    • Petroleum: 38%

    • Coal: 9%

    • Nuclear: 9%

    • Other (including renewables):

    • 1% Geothermal

    • 11% Solar

    • 10% Hydroelectric

    • 18% Wind

    • 5% Biomass

    • 32% Biofuels

  • Data Source: U.S. Energy Information Administration, Monthly Energy Review, April 2024

  • Note: Components may not sum to 100% due to independent rounding.

Energy Terms Explained

  • Work

    • Definition: Application of force over a distance.

    • Measured in: Joules (J).

  • Energy

    • Definition: Capacity to do work.

  • Power

    • Definition: Rate of energy flow.

    • Measured in: Watts (W), equivalent to 1 J/s.

Light Bulb Application Example

  • Powerplant Example: Supplies 1,000 Megawatts (MW).

  • Household Metrics:

    • Supports 640,000 American households.

    • Supports 1.3 million European households.

Energy Consumption by Device (Table 19.2)

  • Average Energy Use per Year (kWh/year):

    • Computer: 100 W

    • Television: 125 W

    • Incandescent Bulb: 250 W

    • LED Bulb: 10 W

    • Dehumidifier: 400 W

    • Dishwasher: 600 W

    • Electric Stove/Oven: 650 W

    • Clothes Dryer: 900 W

    • Refrigerator: 1100 W

  • Source: U.S. Department of Energy.

  • Note: Actual rates may vary significantly.

Energy Use per Person (2024)

  • Measured: Kilowatt-hours (kWh) per person using substitution method.

  • Graphical Representation: Range from 0 to 100,000 kWh per person indicating various electricity uses globally.

  • Data source: U.S. Energy Information Administration (2025)

Power and Efficiency

  • Power Defined:

    • Application of force over a distance.

    • The capacity to do work.

    • Rate of energy flow.

    • Efficiency of work done is crucial in energy discussions, impacting consumption and technological advancements.

Coal Overview

  • Origin: Derived from the “carboniferous period” (approximately 286-360 million years ago).

    • Key to fueling the Industrial Revolution.

    • Grades of coal vary; anthracite coal has the highest carbon concentration and lowest volatiles (like sulfur).

  • Distribution: Coal deposits are relatively evenly distributed across the Earth.

Coal Mining in the U.S.

  • Trends: Decreasing coal use and mining activities due to:

    • Automation leading to reduced employment.

    • Market shifts favoring cheaper fossil and renewable alternatives.

Waste Product: Coal Ash

  • Composition: Contains radioactivity, arsenic, mercury, and other toxins.

  • Storage: Typically stored in reservoirs; however, regulations are changing.

  • Incident: 2008 Kingston Coal Ash Spill released 1.1 billion gallons of ash into local rivers and communities.

Oil Overview

  • Importance: Dominant fossil fuel with a complex extraction and consumption landscape.

  • Extraction Challenge: The concept of “peak oil” has been challenged due to new extraction methods and discoveries.

  • Origin: Formed from marine algae and plankton rather than terrestrial vegetation (as opposed to coal).

Proved Oil Reserves

  • Top Countries (Billions of Barrels):

    • Venezuela: 302.3

    • Saudi Arabia: 266.2

    • Canada: 170.5

    • Iraq: 148.8

    • Kuwait: 101.5

    • UAE: 97.8

    • Russia: 80.0

    • Iran: 157.2

    • Nigeria: 37.5

Expanding Oil Supplies

  • Techniques to increase oil supply include:

    • Hydraulic fracturing (fracking).

    • Extraction from tar sands.

    • Deep-sea wells distinction between conventional and unconventional wells.

Natural Gas

  • Composition: Primarily composed of methane (CH₄).

  • Geographic Distribution: Not evenly distributed like coal; majority reserves are located in the Middle East and Russia.

  • Extraction Concerns: Fracking contributes to environmental issues, releasing 3-8% methane into the atmosphere, which is more potent than CO₂.

  • Future Exploration: Methane hydrates, found in ocean and permafrost, hold substantial potential for energy supply, estimated at 10,000 gigatons of carbon.

Nuclear Energy Overview

  • Global Influence: Supplies 11% of the world’s energy; contains common elements from Earth's crust.

  • U.S. Uranium Reserves: 1% of global reserves; Australia and Kazakhstan hold significant portions of global reserves (20% and 15% respectively).

Nuclear Power Plants in North America

  • Major US Nuclear Plants with Output Capacities:

    • James A. Fitzpatrick: 852 MW (Commissioned 1975)

    • Nine Mile Point: 621/1140 MW (Commissioned 1974/1987)

    • Indian Point: 1020/1025 MW (Commissioned 1974/1976)

    • Robert Emmet Ginna: 498 MW (Commissioned 1970)

U.S. Uranium Imports (2018)

  • By source in millions of pounds:

    • Canada: 9.6

    • Kazakhstan: 8.2

    • Russia: 5.4

    • Australia: 7.2

    • Namibia: 2.2

    • Uzbekistan: 2.5

Nuclear Reactor Functionality

  • Operation Steps:

    1. Heat generated from nuclear reactions turns water into steam.

    2. Steam drives a turbine.

    3. Turbine activates generator to produce electricity.

    4. Electricity is sent to the grid.

  • Safety Considerations:

    • Normal operation entails water circulation for cooling.

    • Worst-case scenarios highlight risks of overheating and potential core meltdowns.

Thorium Reactors

  • Advantages:

    • Thorium is three times more common than uranium in Earth’s crust.

    • More efficient energy production and less hazardous waste storage time (300 years for thorium as opposed to 100,000 years for uranium).

  • Challenges:

    • Initial radiation produces gamma rays.

    • High startup costs and no approved designs available.

Current Issues and Reflections

  • Olkiluoto 3 Nuclear Plant:

    • Came online April 2023, faced significant cost overruns from €3 billion to €11 billion.

    • Poor management and lack of experienced contractors contributed to delays and issues.