Energy FUN damentals
The Good News “The increase in the internal energy of a system is equal to the amount of energy added by heating the system, minus the amount lost as a result of the work done by the system on its surroundings.” HUH? 1 st law of thermodynamics
The Good News The amount of energy in the universe is constant. Energy is neither created nor destroyed
Forms of Energy mechanical (kinetic)
Forms of Energy heat (thermal)
Forms of Energy electrical
Forms of Energy Chemical 1
Forms of Energy Chemical 2
Forms of Energy Solar (radiant)
Forms of Energy Nuclear Fission
Forms of Energy Nuclear Fusion
Energy Transformations electrical light (radiant) + heat
Energy Unit Conversions 1 Btu = 1055 JJ (Joules) 1 Btu = 252 calBtu (British thermal units) 1 Cal = 1,000 calcal (calories) 1 Cal = 3.97 BtuCal (food calories) 1 kWh = 3413 BtukWh (kiloWatthours) 1 therm = 100,000 Btu
Energy Equivalents 1 barrel (bbl) crude oil = 5,800,000 Btu 1 gal gasoline = 124,000 Btu 1 ton (2,000 lbs) bituminous coal = 25,000,000 Btu 1,000 cubic feet natural gas = 1,035,000 Btu 1 gram Uranium (235U): Nuclear Energy = 78,400,000 Btu 1 gram Deuterium (2H): Sun Energy = 225,000,000 Btu 1 mass-gram any solid: E= mc 2 energy = 85,000,000,000 Btu
The Bad News What?
The Bad News Energy always flows downhill (from a hot body to a cold one)
The Bad News The disorder of a system can never decrease
When energy is transformed some energy is “lost”
When energy is transformed some energy is “lost” as heat
energy loss in a car
Generation of Electricity I
Generation of Electricity II
Generation of Electricity III
Generation of Electricity IV
Coal = Chemical Heat + Light Steam = Heat Mechanical + Turbine = Mechanical Electricity Power Lines = Electricity Electricity waste
Why doesn’t the earth run out of useable energy?
The Sun is pumping energy into the earth’s atmosphere 24/7