Monday, June 6, 2016

Falling Down the Energy Ladder.

This is an interesting read compiled by Viv Forbes from “Carbon Sense”, with help from volunteer reviewers. And, cartoons from Steve Hunter, Cartoonist  June 2016. To view the entire article and see the cartoons, Click here. - Werner
***
When man first appeared on Earth he had no implements, no clothes, no farms, no mineral fuels, no machines and no electricity – his only tools were his brains, hands and muscles.

Everything that enables humans to live comfortably in a world where nature is indifferent to our survival has been discovered, invented, mined or manufactured over thousands of years by our inquisitive and innovative ancestors.

The history of civilization is essentially the story of man’s progressive access to more efficient, more abundant and more reliable energy sources - from ancestral human muscles to modern nuclear power. It is also the story of how to store that energy and deliver it with minimal losses to where it is most needed.
There are seven big steps on the human energy ladder –
1.    Stone age energy – human energy, fire, stone tools and geothermal energy
2.    Energy from farmed animals and plants
3.    Solar Power - wind and water
4.    Gunpowder and explosives
5.    Coal, steel, the steam engine and electricity
6.    Oil/gas and the internal combustion engine
7.    Nuclear power

Stone Age Energy.
Every person on Earth today is descended from a survivor of the recurring Pleistocene Ice Ages. They survived only because they were able to extract energy from a cold, dry, barren environment. Initially human energy was used to harvest the solar energy concentrated in animals hunted and plants gathered. Some societies multiplied their limited human energy by capturing and using slaves.

Ancient man’s first and greatest step up the energy ladder was discovering how to harness and use fire for warmth, cooking, hunting, metal working and warfare. This ability to ignite and control fire is the one thing that clearly separates humans from every other species.For centuries the main fire-energy fuels were organic natural resources such as wood, charcoal, peat, grass, animal dung and fats/oils extracted from animals and plants. As human population increased, these energy sources became scarce as the land and seas around towns and villages were stripped of their natural carbon fuels.

Moreover, when great ice sheets covered much of the northern hemisphere, trees and firewood were scarce. Also at this time, the large northern hemisphere land surface was absorbing less solar energy because of variations in Earth’s orbit, tilt and reflectivity. Keeping warm was very difficult. But there is usually more volcanic activity at the turning points of major climate cycles. Some lucky cave men discovered geothermal energy - they could bathe and cook in volcanic springs and hot mud, getting pleasure from the warmth, and health benefits from the trace elements present. Geothermal energy also allowed Stone Age people to harvest evaporites containing essential minerals like sulphur and salts of sodium, calcium, magnesium, copper and boron.

Early humans also discovered that stone-age sticks and stones could help them apply their muscle energy more effectively – with more force or at a greater distance.They used sticks for waddies, digging tools, spears, boomerangs, clubs and later bows and arrows; and stones for clubs, grinders, axes, knives and spear and arrow points. These tools increased their hunting ability, providing food, furs and feathers to generate and conserve body energy.

The Development of Farming.
The second step on the energy ladder was built when some smart hunter/gatherers discovered how to access more reliable energy by domesticating animals and plants. This lead to more permanent settlements where sheep, cattle, goats and pigs provided a steady supply of carbon-based food energy, and dogs, horses, donkeys and camels multiplied human energy for transport, hunting and warfare. Farmers also nurtured fruiting trees and grasses such as einkorn, wheat, rice, barley, oats, corn and sugar cane. These provided more dependable and abundant food energy for humans and their animals.

Farmers were soon producing surpluses, which lead to the development of farmers’ markets, which are energy conservation mechanisms. Initially farmers bartered with tool-makers and hunters, but the difficulty of matching the needs of buyers and sellers and the wish to store values from good seasons for use in bad seasons, led to the development of special stores of value/energy that came to be called money – shells, gems and eventually precious metals such as gold and silver were found to supply the best money.

Solar Power.
About this time humans ascended the third step on their energy ladder – the ability to harness wind/hydro/solar power for sailing ships, windmills, water-wheels, grain mills and drying food. The low energy density and unpredictability of these weather-dependent energy sources was obvious, even to our ancestors. Sailing ships and windmills could be becalmed for days and then have their sails torn down by violent storms. So the ancient wind-powered societies became keen weather-watchers. They read the signals of winds and clouds, waves and tides and carefully recorded the cycles of the weather and the solar system. Some who follow their methods produce better weather and climate forecasts than today’s computer models .

Gunpowder and Explosive Energy.

The fourth big step was the invention of gunpowder by the Chinese, which gave humans the first glimpse of the enormous power of concentrated chemical energy. The initial “black powder” was made by grinding and mixing naturally occurring charcoal, sulphur and saltpetre. Modern explosives such as dynamite and TNT were manufactured using acids and glycerine. There were many industrial accidents before safe methods of manufacture and transport were invented. The energy concentrated in explosives led to their widespread use for hunting, armaments, civil engineering and entertainment. Modern mining and quarrying is totally dependent on the use of explosive energy.

Coal, Steel, Steam Engines and Electricity.
The fifth energy step was gigantic, with three elements – coal, the steam engine and electricity. Coal has been used for centuries for cooking, home heating and black-smithing (when Captain Cook sailed up the Australian coast in 1770, he had a supply of coal in the hold of his wind-powered ship, “The Endeavour”.)

The real energy revolution was born in the 1760’s when James Watt developed a more efficient coal-powered steam engine. Then in 1829, Robert Stephenson developed a practical steam-powered rail locomotive. Suddenly coal-powered steam engines were moving trains and ships, pumping water and powering factories, traction engines and road vehicles. Early steam engines were driven by coal, but other hydro-carbons, wood, concentrated solar energy or nuclear power can be used.

Some coals convert to coke when heated in the absence of air. This was used as a cleaner fuel in homes as well as becoming an essential raw material to produce the iron and steel that built our modern world. Electricity generated by steam engines powered by coal was the magic tool for making clean energy available cheaply to city dwellers. Coal also provided the raw material for coal gas, which could be stored and supplied easily by pipe for heating and lighting.

Suddenly these two clean silent fuels, coal gas and coal-fired electricity, made redundant all the whale oil lamps, candles, kerosene lanterns, wood burning stoves and coal burning boilers and open fires that were truly polluting the air in homes and cities with smoke, ash, dust, sulphur, soot and at times, the deadly carbon monoxide. All of these real pollutants are removed in modern coal-fired power stations whose clean controlled emissions are mainly nitrogen, water vapour and carbon dioxide, all non-visible, non-toxic, plant-friendly natural gases of life.

Oil and the Internal Combustion Engine.
 

The sixth step on the energy ladder also transformed our world - the discovery and extraction of oil and gas and the invention of the internal combustion engine. The mighty coal-fired steam engine still dominates electricity generation, but the compact and powerful internal combustion engine won the battle to power mobile machines. Suddenly cities that were choking with horse manure found relief in petrol-driven cars, buses and trucks. Being easier to store and transport, oil also replaced coal in ships and was soon powering the mighty British navy, and later still, powered civil and military air fleets.

Steam cars and electric cars got a good work-out over 100 years ago, but neither could compete with the oil-powered internal combustion engine. These two engines, the coal-powered steam engine and the oil/gas-powered internal combustion engine created the modern world and still provide most of our warmth, light, food, water, mobility and industrial power. The energy density and abundance of these two hydro-carbon fuels gave an enormous boost to human access to energy, and massively relieved the pressure on natural “green” fuels from forests, whales, bees and animal fats.

The transformation of transport was remarkable. Just 3-4 generations ago, a team of up to twenty bullocks took days or weeks to haul a wagon-load of wool bales, forest logs or bagged wheat to markets, and the bullocks needed fresh supplies of feed and water every night.
**
My thought for today. - Werner
We all live under the same sky, but we don't all have the same horizon. Konrad Adenauer

No comments: