Lecture 3 GEOS24705

Wrap-up of global energy fluxes Beginning of history of technology

Copyright E. Moyer 2010

Average land/person on Earth is 20,000 m2

Equivalent to University of Chicago Quadrangle

Ice

Arable

Desert

Rainforest

Forest

Average arable land/person on Earth is 2500 m2

Equivalent to ½ of Harper Library Quadrangle

Arable

U.S. has relatively high arable land per person

Sources: various internet, unverified. Note that some sources consider “arable” to mean “potentially cultivated” and others to mean “actually cultivated”

Arable/cap (m2) %

Canada 15,000 05 (?) Russia 8500 07 U.S. 6000 19 World av. 2600 13 Saudi Ar. 1400 02 India 1400 49 Rwanda 1200 46 China 1100 15 Bang. 500 55

DRC 43,000 >50 used 2500 03

Average land/person in U.S. is 30,000 m2

Equivalent to University of Chicago Quadrangle

U.S. arable

Bangladesh (total) Bangladesh (arable)

GEOS24705

History of technology How did we go from 100W to 10,000 W?

From V. Smil

200 W 1500 W 4500 W 10,000 W

How did energy use change between Medieval times and present day?

?

From V. Smil

200 W 1500 W 4500 W 10,000 W

Two radical jumps in energy use over history: rise in production (19th century) and transportation (20th century)

In earliest human history the only “engines” were people

Maize farmer, somewhere in Africa, 2007 Source: CIMMYT

In earliest human history the only “engines” were people

Ploughing by hand, Uganda

Diderot & d`Alembert eds, Encyclopédie méthodique. Paris 1763-1777 & 1783-87.

In most of the world, people quickly adopted more powerful “bio-engines”

W.H. Pyne, Microcosm or a pictoresque delineation of the arts, agriculture and manufactures of Great Britain … London 1806.

In most of the world, people quickly adopted more powerful “bio-engines”: and increased power

Horse drawn plough, northern France, likely 1940s. G.W. Hales; Hutton Archives

Horse engine-plough still in use up through the 1940s

Wheat harvest, Hebei Province, China, 2007 (source: www.powerhousemuseum.com)

Harvesting by hand is tedious and slow

Horse drawn combine, likely 1910s-20s. Source: FSK Agricultural Photographs

“Bio-engines” and some technology make harvesting much more efficient.

27 horsepower! (or perhaps horse-+mule-power)

Horse-drawn combine, Almira, WA, 1911. W.C. Alexander. Source: U. Wash. library

“Bio-engines” and some technology make harvesting much more efficient.

~27 horsepower may be practical upper limit

Ploughing with camels, Egypt, early 1900s

Both photos from “messybeast.com”, public domain

“Bio-engines” must be suitable for location and task

Ploughing with oxen, Sussex Downs, England, 1902. Oxen are preferred in heavy soil because they have more “pulling power” (what we’d now call “torque”)

Rotation: animal powered wheels have a long history

Grindstone, China from the encyclopedia “Tiangong Kaiwu”, by Song Yingxing (1637)

Clay millers, W.H. Pyne, London (1806)

First use: grinding

Human powered wheels persisted into the modern era

Japanese water pump, still used in 1950s

Lathe, late 1700s

Rotational motion is a fundamental industrial need …. Grinding is not the only use of rotational motion.

Other sources of rotational kinetic energy: wind and water

Vertical-axis Persian windmill, 7th century (634-644 AD) or later

Vertical-axis waterwheel 1500s or earlier

Very early a switch was made from vertical to horizontal axes

Pitstone windmill, believed to be the oldest in Britain.

Horizontal-axis waterwheel

Pluses & minuses for horizontal axes

Industrial windmil cogs Post mill diagram, from The Dutch Windmill, Frederick Stokhuyzen

Pluses & minuses for horizontal axes

Minus: * complicated gearing to alter axes * must rotate windmill to match wind dir.

Plus: * increased efficiency (both wind & water)

Industrial windmil cogs Post mill diagram, from The Dutch Windmill, Frederick Stokhuyzen

Why so many windmills in the Netherlands?

Luyken, 1694 Source unknown

Horizontal-axis water wheel engineering is complex

Pumping need not always be done with a wheel

Dutch drainage mill using Archimedes’ screw from The Dutch Windmill, Frederick Stokhuyzen

Rotational mechanical motions were converted to linear motion very early in industrial history

European hammer mill w/ cam coupling, 1556 A.D.

Chinese bellows, 1313 A.D.

Gold refining, France. D. Diderot & J. Le Rond d`Alembert eds, Encyclopédie méthodique. Paris 1763-1777 & 1783-87.

.. and one wheel could then drive multiple machines

Rotational •  Grindstones •  Pumps •  Winches •  Bucket lifts •  Spinning wheels •  Lathes, borers, drilling machines (first use)

Linear •  Hammer-mills •  Beaters •  Bellows •  Saws •  Looms •  Boats

Machines powered by wind & water include:

Wood was burned to make heat for industrial use in a large-scale way.. and coal in common use by 18th century

Copper foundry, France

D. Diderot & J. Le Rond d`Alembert eds, Encyclopédie méthodique. Paris 1763-1777 & 1783-87.

By the late 1700s, scarcity of wood in Europe is prompting import of coal from England.

Wood and coal fired technologies include

Fuel is burnt for •  Heating •  Metallurgy •  Glass-making •  Brewing (drying the malt) •  Baking •  Brick-making •  Salt-making •  Tiles and ceramics •  Sugar refining

“Lack of energy was the major handicap of the ancien régime economies”

--- F. Braudel, The Structures of Everyday Life

18th century Europeans had complex and sophisticated technology, an abundance of industrial uses for energy, and the beginnings of fossil fuel use, but …

What was the 18th century industrial impasse?

All technology involved only two energy conversions

•  Mechanical motion mechanical motion

•  Chemical energy heat

There was no way to use chemical energy other than through the body (human or animal) – no engine other than flesh

Mechanical work for industry was limited in magnitude and location by supply of water and wind, or must use animals

Since coal sources weren’t near water & wind, extracting fuel was itself difficult, limiting supply even for those uses to which it could be put

Newcomen “Atmospheric Engine”, 1712

The first devices that broke the heat work barrier

Savery, “an engine to raise water by fire”, 1698

Note that revolution followed invention by ~100 years – typical for energy technology

What is a “heat engine”?

A device that generates converts thermal energy to mechanical work by exploiting a temperature gradient

•  Makes something more ordered: random motions of molecules ordered motion of entire body

•  Makes something less ordered: degrades a temperature gradient (transfers heat from hot to cold)

The two technological leaps of the Industrial Revolution that bring in the modern energy era

1.  “Heat to Work” Chemical energy mechanical work via mechanical device Use a temperature gradient to drive motion Allows use of stored energy in fossil fuels Late 1700’s: commercial adoption of steam engine

2. Efficient transport of energy: electrification Mechanical work electrical energy mech. work Allows central generation of power Late 1800s: rise of electrical companies

Outline of next three lectures

Fundamental physics of heat engines understanding heat work

History of early steam engines

History of Industrial Revolution ..with preview of electric generation

Organizing framework for energy conversion technology

The modern energy system

And then it’s on to individual energy technologies…

Having finished with global energy flows and started history of human use, well now do a tricky transition…