An Energy History

Energy has been an organizing principle in human evolution and our societies.

This section outlines important transitions in energy sources and uses.

Sources

Biomass

Solar energy enters the food chain through producers and creates energy stores like food. This biomass is the energy source for muscle power both human and animal.

Biological Energy Conversion

  • Plants convert radiant energy into chemical energy
  • Humans convert chemical energy into human activity
  • We essentially burn food in our bodies
  • since all fossil fuel comes from plants, it is essentially solar

Livestock

  • Oxen
  • Horses
  • Allowed humans to cultivate more land, but required more land for food

Fire

Ancient peoples used biomass to create heat.

  • Stored chemical energy in wood to heat

  • Allowed for tool making

  • Allowed for cooking

  • Richard Wrangham, primatologist, argues that cooking saves energy in digestion

Food Gathering Techniques

  • Foraging
  • Hunting
  • Agriculture
  • Livestock

Human Thermoregulation

  • Our superior ability to remove heat energy from our bodies allows us to outrun prey animals

Agriculture

Agriculture was the organized conversion of solar energy to chemical food energy in a way that reduced the calories humans had to expend to harvest that food.

Increased density of calories per area was an important quantifiable benefit.

Water power

  • Water wheels
    • converts kinetic and potential energy in water to rotational motion
    • estimated 500,000 waterwheels in Europe

Water Wheel

Syria Water Wheel

Wind power

  • Windmills
    • converts kinetic energy in the wind to rotational motion
    • Dates to Ancient Greece
    • 12th century in Europe
    • estimated 200,000 windmills at peak in Europe
    • estimated 600,000 windmill waterpumps at peak in 1930 in United States
  • Sailing
    • Allowed long distance travel

Ancient Windmill

Estonian Windmill

American Pumping Windmill

South Dakota Wind Pump

Electrification

  • Pearl Street Station
  • Steam-powered, coal-fired electricity generator
  • Fossil fuel is still widely used for electricity generation

Consequences of Industrialization

  • Increased economic activity
  • Urban pollution
  • Global Warming
    • Widespread use of these fuels causes an increase in fossil carbon in the atmosphere
    • Arhennius in 1896 calculated how changes in the levels of CO2 could alter surface temperature

Energy in the Fossil Fuel Era

  • The modern era is marked by the enormous productivity gains provided by fossil fuel energy
  • We can purchase the equivalent of one person’s labor for a day for about 10 cents

Steam Engine

  • Invented by James Watt in approximately 1770
  • Converts of chemical energy to heat to motion
  • Created shift in manufacturing technology

Petroleum

Oil and gas extraction creates the availability of liquid fuels with advantages over coal.

Internal Combustion Engine

  • Inventions in the 1800s lead to first automobile patent by Karl Benz in 1886
  • The internal combustion engine requires liquid fuels

Energy Uses

Hunting Machines

  • Bow and arrow
    • energy is stored in bow and released quickly
  • Spear and Lever
    • Lever allows hunter to impart more kinetic energy to the spear than with the arm alone
  • Guns
    • Chemical energy converted to kinetic energy in bullet

Lighting

  • Whale oil
  • Kerosene
  • Town Gas
  • Electricity

Transportation

  • Muscle power (walking, horses)
  • Wind power (sailing)
  • Coal power (railroads, steamer ships)
  • Oil power (automobiles)
  • Electrification (automobiles, street cars)
  • Virtualization (computing power removing the need for some transportation)

General Purpose Power

  • Biomass
  • Coal
  • Petroleum
  • Coal/Natural Gas/Oil Electricity
  • Hydropower Electricity
  • Nuclear Electricity
  • Wind and Solar Electricity