Quarter 1 Flashcards
energy
energy of motion (kinetic)
F=1/2mv^2 (Joules)
mass- kg
v- m/s
OR
powertime
ie. J=KWhour
heat energy
1cal = 4 J
Power
power (W) = energy/time (J/s)
1 MW
1*10^6
1 KW
1*10^3
US energy consumption
- Petroleum (35%)
- Natural Gas (31.3%)
- has increased a lot
—————- 1/3 - Coal (10.5%)
- has decreased a lot - Nuclear (8.13%)
- nuclear>renewable
—————— 1/10 - Biomass (4.83%)
- Wind (3.33%)
- Hydro (2.28%)
- Solar (1.5%)
- Geothermal (0.206%)
-renewables have seen major increases (10 yr)
Efficiency
(Useful energy out/ Energy in) < 100%
Heat is most common excess energy
Transportation and alt. energy
boats are most common because weight isn’t a problem - nuclear
Navy- ships/submarines (now only limiting factor for being underwater is food supply/dont need air for energy)
Common energy source tradeoffs
1.costs 2.availibility 3.danger
coal
cheap and abundant
0.4 cents and deposits across the world bc its a fossil fuel
burning -> sulfuric acid -> acid rain + CO2
coal mines are soft and dangerous
fossil fuels
mostly from plants
coal 0.4c, natural gas 0.7c, petroleum (gas 7c)
natural gas
hydrocarbons make less greenhouse gasses
US lowered gg from switching
-whereas problem with natural gas is its volume
C-> CO2
CH4-> CO2 + H20
petroleum (oil)
mix of hydrocarbons (lite CH4 gas, heavy liquid)
refined for different types of fuel
+42,000 J/G compact form of energy
-expensive and gives off CO2 (less than coal)
US is leading producer of oil
production of oil
US only and main until 1940s
Saudi Arabia top 1980s
US largely self dependent for oil
Global East doesn’t produce much
political bc not evenly distributed across world
nuclear power
nuclear fission heat -> boils water for steam
steam creates energy to drive an electric turbine
+produces no greenhouse gas and minimal air pollution
- fear around nuclear power, expensive, radioactive waste
Renewable Energy
solar power, wind power, hydroelectric, geothermal
solar power
photoelectric effect
panels are 15-40%
+ no moving parts, easy setup, no waste
- not available all the time (daylight/not cloudy), cost/efficiency
are getting cheaper and more efficient w time
wind power
runs a turbine
+ no emissions, and no running out
- noisy, hazard to birds, not evenly distributed, costly
great plains is best location
hydroelectric power
2% of power is static because we have used all ideal locations
+ relatively cheap, more reliable
- not many locations (river and dam are perfect conditions the Pacific NW), largest types of power plants, dams can be bad for ecosystem
geothermal
caves are about 55 degrees F all year
deeper caves get warmer and can use their heat energy
2 locations: geysers in Yellowstone, Iceland is 25% of energy source
not very practical for US 2% of energy source
Nuclear Fusion
energy of the future and will always be
Food Energy
100 Cal = 100,000 calories = 400,000 Joules - if it was immediate
Bomb Calorimeter
burning up food to see how much heat given up