Final Numbers To Know Flashcards
Watts per horse power
746
Watts per human power
100
Melting/freezing temperature of water
273.15 K
Boiling point of water at Earth’s atmospheric pressure
373.15 K
Mechanical efficiency of most engines
20%
Electrical efficiency of most electrical motors and electrical generators
90%
Age of the universe
13.7 billion years
Depth of the Earth’s ocean
4 km
Percent of Earth’s surface covered by ocean
70%
Thickness of the Earth’s atmosphere
80 km
Age of the Earth
4.6 billion years
First evidence of life on Earth
3-4 billion years
First evidence of multi-celled organisms
1 billion years
Life first colonizes land
400 million years
First mammals
225 million years
Extinction of Dinosaurs (except for birds)
65 million years
First hominids
5 million years
First modern humans
200,000 years
Date of first human civilization
8000 BC
Start of the industrial revolution
1760
Human population at the start of the industrial revolution
1 billion people
Current human population
8 billion people
Current rate of human population growth
1%
Population in the US
300 million people
Total per capita power utilization in the US
12 kW
Total per capita power utilization in the world
2 kW
The fraction of total energy used for industrial, transportation, commercial and
residential purposes
25%
The fraction of total energy derived from fossil fuel sources
85%
The current EPR for fossil fuels
5-10
The date that domestic oil utilization peaked in the US
1975
The concentration of CO2 in the Earth’s atmosphere
400 ppm
The residence time of CO2 in the Earth’s atmosphere
100 years
The infrared emissivity of most non-metals
1
The infrared emissivity of most metals
0.05
The average rate of Earth’s plate motions
2 cm/year
The average energy of a solar photon
1.4 eV
The approximate efficiency of current single junction silicon solar cells
20%
The density of air at sea level
1.2 kg/ m^3
The thickness of the Earth’s troposphere
11 km
The average speed of west-to-east jet stream winds
25 m/sec
The maximum theoretical efficiency of a wind turbine
59%
The rated power of a large wind turbine
1.5 kW
The energy produced by burning dry biomass
20 MJ/kg
The energy produced by burning liquid ethanol
31 MJ/kg
The time of day of maximum electrical power demand
5 pm
The magnitude of the daily average fluctuation in electrical power demand
+/- 25%
The battery storage capacity of a typical electric car
30 kWh
The energy released during the fission of one 235 U atom
200 MeV
The “safe” annual radiation dose for humans
3 mili-Sievert
The approximate half-life of the most radioactive components of nuclear waste
1000 years
USA’s mode annual family income
$19,000
The year that California will hopefully achieve 100% carbon-free electricity
2045
