Earth Data - Energy

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay

Units

Joule: 1 kg-m²/sec²
- Energy to raise 0.1 kg 1 m
- Energy to raise one pound 9 inches
- Kinetic energy of 0.5 kg moving 1m/sec
Erg: 1 gm-cm² /sec²
- 1 erg = 10 E-7 J
ccalorie (small c) = heat to raise 1 gm of water 1 degree C = 4.2 J
Calorie (large C) = heat to raise 1 kg of water 1 degree C = 4200 J
- Food calories are large C calories
Kiloton: defined as 1 x 10¹² Cal or 4.2 x 10¹² J
Megaton: defined as 1 x 10¹⁵ Cal or 4.2 x 10¹⁵ J

Energy output of sun 3.86 x 10²⁶ W (Joules/Sec)
Mass-Energy Conversion Rate: 4.3 x 10⁹ kg/sec
Solar Energy Flux on Earth = 1.37 W/m²
- Flux per second = 1.37 J/m²
- Flux per day: 118,400 J/m²
- Flux per Year: 4.32 x 10⁷ J/m²
Whole Earth Solar Flux
- Per second: 1.75 x 10¹⁴ J
- Per Day: 1.51 x 10¹⁹ J
- Per Year: 5.51 x 10²¹ J
Rotational velocity of Earth 7.27220 E-5 radians/sec
Rotational Kinetic energy of Earth 2.12 x 10²⁹ joules
Orbital Kinetic energy of Earth 2.65 x 10³³ joules
Potential Energy with respect to Sun 5.299 x 10³³ joules (twice the orbital kinetic energy)
Tidal energy dissipation of Earth: 3.75 x 10¹² W = 1.2 x 10²⁰ J/yr

In the innermost 2% of the sun's radius, about 1% of its energy is produced. The energy output is 230 W/m³ and .0017 W/kg
In the innermost 20% of the sun's radius, about 94% of its energy is produced. The average energy output is 30 W/m³ and .0005 W/kg
The energy density of the solar core is less than that of a birthday candle and much less than the human body.
The Mass-Energy Conversion Rate of the Sun is 4.3 x 10 9 kg/sec. In the innermost 2% of the Sun's radius, that corresponds to 2.5E-15 kg/sec per cubic meter of volume and 2E-20 kg/sec per kilogram of mass
In the innermost 20% of the Sun's radius, that corresponds to 3.5E-16 kg/sec per cubic meter of volume and 6E-21 kg/sec per kilogram of mass
In the innermost 2% of the Sun, there are approximately 3 million fusion events (4H -> He) per kilogram per second, and in the innermost 20%, an average of 900,000 per kilogram per second. A kilogram of H contains 6.02x 10 26 atoms.

Total kinetic energy of plates (100 km thick, v=5 cm/yr, density = 3300 kg/m³ ) = 200,000 J. Utterly negligible.
Energy needed to slide plates (assuming coefficient of friction = 0.2) = 1.7 x 10²² J/yr

M = 4 Earthquake = 6.3 x 10¹⁰ J
M = 5 Earthquake = 2 x 10¹² J = 0.5 Kt
M = 6 Earthquake = 6.3 x 10¹³ J
M = 7 Earthquake = 2 x 10¹⁵ J = 500 Kt
M = 8 Earthquake = 6.3 x 10¹⁶ J = 16 Mt
M = 9 Earthquake = 2 x 10¹⁸ J = 500 Mt
Total global seismic energy release per year is about 1x 10 18 J but is dominated by the very largest events and varies widely from year to year.

Global volcanic energy release = 3 x 10¹⁶ J/yr (About half that of an M=8 earthquake)
VEI 3 Eruption = 2 x 10¹⁶ J (Actual eruptions can vary widely. Vesuvius, 1944)
VEI 4 Eruption = 1.4 x 10¹⁷ J (Eyjafjallajökull, 2010; Mount Pelee, 1902)
VEI 5 Eruption = 9 x 10¹⁷ J (Mount St. Helens, 1980; Vesuvius, 79 AD)
VEI 6 Eruption = 5 x 10¹⁸ J (Krakatoa, 1883; Pinatubo, 1991; Thera, 1650 BC)
VEI 7 Eruption = 3 x 10¹⁹ J (Tambora, 1815)

2000 Calorie daily diet = 8.4 x 10⁷ Joules/day
Power output of human body (2000 Cal/day) = 100 W
- Power output/kg (70 kg average) = 1.4 W/kg
- Power output/m³ = 1400 W/m³ (Assuming humans have roughly the density of water, roughly 14 humans occupy one cubic meter) Compare to the energy density of the center of the Sun, above!
  - Total food energy consumed by all humans (@2000 Cal/day @ 7 billion) = 2 x 10¹⁹ J/yr

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Created 12 August 2003, Last Update 24 May 2020