1. Chapter 12
Nonrenewable Energy

2. Power and Energy
Power – Rate work is done (how fast energy is transferred)
kW, J/S, watts
At any given time
Energy – The ability to do work
kWh is the total amount of energy that has been delivered over a period of time
kWh, cal, J, BTU…
Similar to speed vs. average speed

3. Nonrenewable energy use
Nonrenewable resources cannot be replaced
Fossil fuels are derived from biological matter (coal, oil, and natural gas)
Nuclear is derived from radioactive materials
Amount of energy use depends on availability and affordability
Patterns of use in US
Wood until 1875, than coal followed by natural gas and oil. Nuclear around 1950 and renewable in the 1970s

6. Energy types and quality
To determine best use of energy, we look at energy efficiency ((output/input) * 100)
Gas used for transportation because a small volume goes a long way and it burns easily, but pollutes
Most fossil fuels around 35% efficient
Must know complete picture to choose best fuel and to calculate true efficiency
How much energy does it take to obtain the fuel

9. Electricity generation
Starts with sun, and the potential energy is converted into electricity
Ultimate goal is to spin a turbine (fluid). Usually done with steam (burn coal to get steam)
Spinning turbine spins a generator that creates electricity that gets sent through transmission lines
Capacity is the maximum potential output
Cogeneration is the use of fuel to generate electricity and heat
Can be 90% efficient vs. 35% for just electricity

11. Coal Coal is mostly used for electricity
Coal is solid fossil fuels made from plant remains
Sediments piled up on plant remains and compressed them
Chemical reactions break down chemicals except carbon
Heat and pressure turned this into coal
Stages:
Begins as peat (compressed plant materials)
Lignite (water gets forced out, and becomes 40% carbon)
Bituminous coal (soft coal, 85% carbon)
Anthracite coal (95% carbon) – most available energy
Pros: plentiful, needs minimal refining, lots of energy, inexpensive
Cons: nonrenewable, destroy landscape, runoff, pollution (SO2 and CO2), heavy metal release, acid rain

16. Environmental Impacts of Mining Coal
Surface Mining Control and Reclamation Act (1977)
Requires filling (reclaiming) of surface mines after mining
Expensive!
Reduces Acid Mine Drainage
Requires permits and inspections of active coal mining sights
Prohibits coal mining in sensitive areas

17. Petroleum Petroleum is liquid fossil fuel
Oil and natural gas form from marine phytoplankton
Found where porous rocks are capped by nonporous rocks
Accumulate at bottom of ocean floor
Buried and heated until they became complex carbon molecules
Found in porous rocks covered by nonporous rocks
Makes up fuels, plastics, lubricants, tar, etc
Pros: lots of energy, helps economies, many uses, easy to transport (pipeline)
Cons: pollution (CO2, sulfur, heave metals), oil spills, nonrenewable, plastics, foreign

20. OIL Refining crude oil:
Based on boiling points, components are removed at various layers in a giant distillation column.
The most volatile components with the lowest boiling points are removed at the top.

21. Natural gas Natural gas (CH4) is found with petroleum
Pros: burns cleaner, transported through pipes, many uses, economical
Cons: it is a greenhouse gas itself, leak easily, explosive, nonrenewable

22. Other Fossil Fuels
Bitumen (tar, pitch, or oil sands)- a degraded type of petroleum that forms when a petroleum migrates close to the surface, where bacteria metabolize some of the light hydrocarbons and others evaporate.
To mine for these is very energy intensive
Less efficient
Liquid coal
Lots of coal available, but twice the pollution and more expensive

23. A small house uses two lamps
A small house uses two lamps. Both lamps have a 60-watt light bulb which are used for 3 hours per day. The family watches 2 hours of television per day. The TV uses 200 watts. Finally, they run the ceiling fan in the living room while watching 2 hours of television. The fan uses 90 watts. The cost per kWh is 10.5 cents. Calculate the total cost of all the appliances for one year.

24. Fossil fuels are finite
Less that 40 years of oil likely remain
Slightly longer for natural gas
At least 200 years of coal

25. US Energy Strategy
Objective 1: Increase Energy Efficiency and Conservation
Objective 2: Secure Future Fossil Fuel Energy Supplies
Objective 3: Develop Alternative Energy Sources
Objective 4: Meet the First Three Objectives Without Further Damage to the Environment

26. Nuclear energy Nuclear energy is energy from the nuclei of atoms
Nuclear fission splits an atom, nuclear fusion sticks atoms together
Forces that hold nucleus of an atom together are extremely powerful
Uranium-235 is used for nuclear fission, the splitting of atoms
If you bombard the nucleus of a uranium atom with neutrons, the atom will split and release more neutrons that will split more atoms (chain reaction (atomic bomb))
Heat turns water to steam and spins a turbine

28. How it works Split the atoms
Fuel rods are cylindrical tubes that contain uranium pellets
Metal control rods absorb excess neutrons to avoid an uncontrollable reaction
Control rods are lowered between fuel rods to control the rate of fission (absorb excess neutrons)
Water is between fuel and control rods to act as coolant
Heat release generated electricity
Breeder reactors use uranium-238 which produces plutonium in the end. Makes more fuel!
Meltdown far more dangerous, and nuclear weapons easy

30. Advantages and disadvantages
Pros
Very concentrated (1” pellet = 1 ton of coal)
Not much pollution
Less radiation than fossil fuel plant
Cons
Expensive to maintain and build
Need to store and move nuclear waste ( thousands of years)
Meltdowns
Thermal pollution
Nuclear weapons

33. Nuclear fusion Future is nuclear fusion, or the combing of nuclei
This powers stars
Unlimited source of energy
Need temps of 180,000,000F
Takes more energy to produce then return
Cup of water could power a city for 100 years
We’ve created it, but not contained