Post on 20-Dec-2015
Human Energy Use
Do Now:
Define: Energy
Where does most of the energy used by humans come from?
Energy
• Physics: The ability to do work (=Fd)
• General: The ability to cause change.
• Units: Joule (SI) Calorie (English) kCal (dietary calorie
• Laws of thermodynamics:– 1: Energy cannot be created or destroyed– 2: No transformation of energy is 100%
effiicient (entropy increases in a closed system)
Human Energy
• 80-90% of the energy used by Homo sapiens is produced by the combustion (oxidation) of fossil fuels…
It all started waaaaaay back…
The energy stored in the fossil fuel we use today was first captured by plants millions of years ago.
Geology Takes a Turn
Coal formationOil & gas accumulation
Getting it out of the ground
Offshore oil rig
Open pit coal mine
Crude Oil is Organic Chemicals
There’s thousands of different chemicals in oil that comes out of the ground.
The different parts or
“fractions” must be
separated before
they’re used
Oil Refinery
What about coal?
The combustion of coal produces more CO2 than equal amounts of any other fossil fuel
Most Coal is Used to Produce
Electricity
What Homo sapiens Use Energy To Do
Consequences
Humans have consumed more crude oil than they have discovered for over 20 years now.
Metabolism with Global Consequences
Human Population Growth
The Effect of Resource Depletion and Toxin
Accumulation on a Population
What to do?We must begin using less energy – whether
we want to or not.
Life on Earth has relied on the sun’s light as it’s primary energy source for
billions of years.
Solar Panels: 2 designs
Our technology is what truly makes our species unique on Earth. Use the best brain and hands that evolution has ever produced to make a difference.