1. Nonrenewable Energy Resources
Oil refinery in Antwerp, Belgium
All energy use has consequences

2. Nonrenewable resources= once they are used up, they cannot be replenished
Minerals
Fossil Fuels
Nuclear Fuels

3. Biological material that became fossilized millions of years ago
Fossil Fuels
Nuclear Fuels
Biological material that became fossilized millions of years ago
Coal
Oil
Natural Gas
To access the energy contained in the chemical bonds, we burn these fuels & harness the heat energy
Radioactive materials that give off energy
We harness the energy by transferring heat, just like with fossil fuels

4. Worldwide Energy Use Basic unit of energy= joule (J)
8 gallons of gasoline= 1 x 109 J (1 bill. Joules)
I gigajoule (GJ)= 1 billion joules
1 exajoule (EJ)= 1 billion GJ
Energy sources used in US & worldwide, in order of increasing importance=
#1 Oil #2 Coal #3 Natural Gas

6. Commercial Energy Sources Subsidence Energy
Those that are bought and sold
Coal, oil, natural gas
Developed countries & some urban developing countries they use coal, oil & natural gas for electricity generation
Those gathered by individuals for their own needs
Rural areas of developing countries use wood, charcoal or animal waste for energy

7. Energy Consumption in the US since 1850

8. Energy use in U.S.
Midwest & southeast: coal primarily burned for electricity
West & northeast: use a mix of nuclear fuel, natural gas & hydroelectric dams
Highly populated areas tend to use less coal because it creates the most air pollution of any fuel
Northern areas use more oil & natural gas during winter months, southern areas consume more during summer months.
Type of energy used depends on ease of transportation and the amount of energy a given mass of fuel contains
Type of energy used depends ease of on transportation and the amount of energy a given mass of fuel contains

9. The US produces 70% of its energy needs
What we produce
Where the energy is being
used

10. Quantifying Energy Efficiency
The efficiency of obtaining the fuel
The efficiency of the process that converts it into the work that is needed
2nd Law of Thermodynamics: when energy is transformed, some of the energy is lost

11. Energy invested to obtain the fuel
Every energy source, from coal to oil to wind, requires an expenditure of energy to obtain it.
The most direct way to account for energy required to produce a fuel is energy return on energy investment (EROEI)
EROEI= Energy obtained from the fuel___
Energy invested to obtain the fuel
Ex. In order to obtain 100J of coal from a surface coal mine, 5J of energy is expended. Therefore, EROEI= 20 J
A larger value for EROEI suggests a more efficient & more desirable fuel source
Hot water tank: would be more efficient if electric hot water heater converted electricity to heat inside the tank (electricity made from coal)- 99%
Natural gas (flame below tank) water tank is 80% efficient. But when we take into account the cost of extracting, transporting, and processing, the coal/electricity water tank actually comes out to only 35% efficient

12. Efficiency of Transportation
If there were 4 people in the car, it would be the most efficient, but most cars on roads are single-occupant

13. Overall fuel efficiency of U.S. automobiles
Light trucks (including SUVs, minivans, and pickup trucks) account for ½ of total automobile sales
Hybrid vehicles account for 2-3% of total sales

14. Fuel efficiency Type of vehicle Miles per gallon on the highway
Light trucks 20
Small cars 45
Hybrid cars 50
Electric cars & plug-in hybrid electric cars
Most efficient

15. Electricity generation

16. Coal, oil, and natural gas are primary sources of energy
Electricity if a secondary source of energy, meaning that we obtain it from the conversion of a primary source
Electricity is an energy carrier: something that can move & deliver energy in a convenient, usable form to end users
40% of the energy used in the U.S. is used to generate electricity
However, because of lost energy, only 13% is available for end use!
35% efficient

17. Electricity
Electricity can be produced by conversion of coal, natural gas, or wind, just to name a few.
Electricity is clean at the point of use
No pollutants are emitted in your home when you use the electricity
However, when it is produced from fossil fuels, pollutants are released
It is only 35% efficient but it is convenient

19. How electricity is made
1. Fuel (coal, n.gas, wind) is delivered to a boiler, where it is burned
2. Burning fuel transfers energy to water, which becomes steam.
3. The kinetic energy contained within steam is transferred to the blades of a turbine
Turbine= a large device that resembles a fan or a jet engine

20. How electricity is made
4. As the energy in the steam turns the turbine, the shaft in the center of the turbine turns the generator, which generates electricity.
5. The electricity generated is transported along a network of interconnected transmission lines known as an electrical grid, which connects power plants together and links them with homes, businesses, factories, etc., where it is converted into heat energy for cooking, kinetic energy in motors, radiant energy in lights, or used to operate electronic & electrical devices

21. How electricity is made
6. The water used in the generation of electricity is sometimes cooled in a cooling tower or discharged into a nearby body of water.
Thermal pollution
Lowers the amount of dissolved oxygen
How is water used worldwide: #1 agriculture, #2 industry, #3 domestically (toilets)

22. Electricity plants They are not operational 24 hrs/day, 365 days/year
Have to be shut down for maintenance, refueling or repairs
When its time to start them up again, nuclear & coal-fired plants may take a number of hours or even a full day to reach full generation capacity
For this reason, electric companies tend to keep them running at all times

23. Energy math problem
If a power plant created 500 megawatts (MW) in an hour, then…
In a day it would generate 500 MW x 24hrs= 12,000 megawatt-hours (MWh)
Most home electricity is measured in kilowatt-hours (kWh)
12,000 MWh= 12,000,000 kWh

24. Power vs Energy Power measures the rate at which energy is being used
Units of power (equal to joules/sec):
Kilowatt
BTU
Unit of energy:
Joule
Energy is what you deliver and power is the rate at which you deliver it
The power rating of different appliances tells you how fast they consume this energy. A 100 watt bulb will use energy at a faster rate than a fluorescent bulb that has a power rating of 10 watts.

25. Cogeneration
The use of a fuel to generate electricity and produce heat is known as cogeneration
A method for obtaining greater efficiencies
Instead of releasing heat energy through cooling tower or flue gas, the heat energy is sent to nearby facilities to be used for water or space heating
Cogeneration= 90% efficient
Steam heating alone= 75%
Electricity generation alone= 35%

26. Trigeneration

28. Fuels used for electricity generation in the United States