Energy !

How Electrical Energy is made commercially.By E. B. Allred

Commercial Energy Sources• Coal• Oil• Natural Gas• Nuclear• Hydro • Geothermal• Wind• Waste Methane• Solar

Coal

Delta Utah

After coal is unloaded from trains, it is pulverized to fine powder and blown into the furnace where is explodes in the flame. Water in pipes in the furnace turns into high pressure steam that is sent to the turbine.

Coal fired electrical power plant

Coal fired electric plants require thousands of tons of coal per day. Coal plants have been fitted with exhaust “scrubbers” and ash traps but are still a significant source of atmospheric pollution. Coal is a non-renewable resource. Coal and Oil are a form of stored solar energy, from plants and animals that lived long ago.

Steam made in the coal furnace is piped into the turbine that spins the generator.

There are about 620 coal fired power plants in the United States. (DOE)

America gets 50% of its electrical power from coal fired plants. (NEF)

OilBoilers burn fuel oil to make steam which is routed to a turbine that is connected to a generator.

Although cleaner than coal, oil creates air pollution too.

America gets about 2% of its electricity from oil (DOE).

Most oil is used in transportation rather than electricity generation.

Oil is a non-renewable energy source.

America imports over 50% of the oil it consumes. The U.S. is the world’s largest oil consumer. (NEF)

Natural Gas Electrical Generation

Natural gas has the lowest carbon dioxide emissions of all fossil fuels. Natural Gas is a non-renewable resource.America gets about 22% of its electrical energy from natural gas. (NEF)

1. Cooling tower 10. Steam control valve 19. Superheater

2. Cooling water pump 11. High pressure steam turbine 20. Forced draught (draft) fan

3. Three-phase transmission line 12. Deaerator 21. Reheater

4. Step-up Transformer 13. Feedwater heater 22. Combustion air intake

5. Electrical generator 14. Coal conveyor 23. Economiser

6. Low pressure steam turbine 15. Coal hopper 24. Air preheater

7. Boiler feedwater pump 16. Coal pulverizer 25. Precipitator

8. Surface condenser 17. Boiler steam drum 26. Induced draught (draft) fan

9. Intermediate pressure steam turbine 18. Bottom ash hopper 27. Flue gas stack

Power plants using coal, natural gas, or fuel oil are typically about 50% efficient, meaning that at least 50% of the energy is wasted, unusable for electrical power generation.

Simplified thermal power station

Nuclear Power

Heat from the reactor core is transferred from the radioactive loop to the non-radioactive water loop through a heat exchanger where it makes high pressure steam for a turbine to spin a generator to make electricity. From 65 nuclear power plants, America gets almost 20% of its electricity from nuclear power plants. (DOE)

What about Nuclear waste?

The spent fuel from a nuclear power plant is dangerously radioactive, and will remain that way for about 25,000 years. Where can it be stored safely?

Except for radioactive waste, nuclear power makes no pollution. It is estimated uranium supplies can last 50 to thousands of years, depending on technology used.

Nuclear Energy is a non-renewable energy resource.

Hydro

How a hydroelectric dam works

Generators that make the electricity require a lot of power to spin them. Water flowing through the turbines spins the generators.

America gets only about 6% of its electricity from hydroelectric dams. (National Energy Foundation)

Geothermal

A geothermal electric plant operates just like a coal fired plant except that the heat source to make steam comes from hot water or steam under ground.

After hot water cools off it is pumped back underground. This completes a “closed loop”, just like in a nuclear power plant.

Steam is piped to turbines that spin an electric generator. Cooling towers condense used steam back into water to be reheated again underground.

America gets about 1% of its electricity from geothermal plants. (DOE)

Wind

Wind powered electrical generators rely upon a steady wind. Wind generators are placed where wind is frequent such as canyons and slopes of hills.

America generates only about 0.5% of its electricity this way. (NEF)

Wind power is expected to have a much greater role in the future.

Biomass

Garbage methane wellsRotting garbage creates lots of methane gas. Methane gas is buried under a layer of topsoil where it is collected in “wells” and piped to large engines that burn the methane, and in turn, spin electric generators.

Methane burns cleaner than other fossil fuels, but it still produces air pollution.

Biomass is considered a renewable resource, supplying less than 1% of our energy . (NEF)

Photovoltaic (PV) electrical power generation is an Emerging Technology.

PV cells create electricity directly from sunlight. Typically, they are only about 15% efficient. (NEF)

Photovoltaic cells are only a minor contributor to U.S. electricity.

Solar

Solar

Solar concentrating reflectors (mirrors) are used to make intense heat from sunlight. This heat makes steam, used to turn turbines, to generate electricity.

Solar Concentrator Electrical power plant

Concentrating solar radiation to make heat is a much more efficient way to make electricity from sunlight. America gets about 0.5% of its electricity from solar power. (NEF) This is an Emerging Technology.

year Coal OilNatural Gas Nuclear Hydro

Other Renewables

1996 52% 2% 13% 20% 10% 2%

1997 53% 3% 14% 18% 10% 2%

1998 52% 4% 15% 19% 9% 2%

1999 51% 3% 15% 20% 9% 2%

2000 52% 3% 16% 20% 7% 2%

2001 51% 3% 17% 21% 6% 2%

2002 50% 2% 18% 20% 7% 2%

2003 51% 3% 17% 20% 7% 2%

2007 49% 2% 22% 19% 6% 3%

2016 30% 0.6% 34% 20% 6.5% 8.4%

Misc. Review Facts1. Coal generates about 23% of the electricity in the USA.

2. Solar, wind, Geothermal, and hydroelectricity generate no pollution.

3. Nuclear power generates radioactive waste that is difficult to dispose of.

4. Coal, oil, natural gas, and methane systems generate atmospheric pollution.

5. Nuclear power generates no air pollution.

6. Nuclear, oil, coal, methane, and Geothermal systems operate independently of the weather.

7. Solar, wind, and hydroelectric systems depend on the weather.

8. Solar, wind, and geothermal systems are emerging technologies.

9. The United States has enough coal to power the world for the next 100 years.

10. Hydroelectric systems depend on large reservoirs or constant flowing streams and rivers, so they are limited in number because of available places to build them.

More Misc. Review 11. A nuclear reactor’s heat is transferred through a heat exchanger.

12. Typical photovoltaic (PV) cells are presently only about 15% efficient.

13. A great deal of energy, typically, up to 50% in any (thermal) electric generating plant is lost to excess heat.

14. A steam or gas turbine is very much like a jet aircraft engine.

15. A hydroelectric turbine is very much like an aircraft or boat propeller.

16. Photovoltaic cells (PV) convert sunlight directly into electricity.

17. Coal and oil is a form of stored solar energy.

18. Today’s oil production has PEAKED and isdeclining.

19. Geothermal systems are limited in number because of the depth of most hot layers of rock.

20. Natural gas is the cleanest of the fossil fuels.

Commercial Energy Sources Quiz

1. Are there good jobs & careers in the energy production business?

2. What type of power plants generate the most electrical energy in the United States?

3. Name two energy producer methods that do not pollute our environment.

4. Which type of energy production generates the most pollution?

5. Is solar-electric energy production a major or minor producer of electricity in the United States?

6. What is the most challenging problem related to nuclear electric power production?

Quiz Continued

7. Name two means of electrical production that do not depend upon the weather.

8. Name two means of electricity production that are considered emerging technologies.

9. Which type of electrical generation depends on good rainfall and/or snow pack?

10.Which is the cleanest of the fossil fuels to burn?

11.Which country is the world’s largest oil consumer?

12.Which is more efficient, photovoltaic cells or concentrating solar heat for electrical generation?

Quiz Continued

13.Define a renewable energy resource.

14.Which energy type of generation smells bad but is considered a fairly clean (nonpolluting) and renewable resource?

15.What is the easiest and simplest thing that can be done to decrease electricity consumption in the United States ?

Quiz Answers

1. Yes, there are good jobs and careers in energy production.

2. Coal fired electrical generating plants.

3. Wind and Solar electrical generation plants.

4. Coal fired generators create the most pollution.

5. minor

6. dealing with radioactive waste.

7. Any 2 of: nuclear, coal, oil, natural gas, geothermal

8. Any 2 of: wind, solar, geothermal, oil shale, clean coke, biofuels or waste methane.

9. Hydropower

Quiz answers

10.natural gas 11.United States of America

12.concentrating solar heat

13.Energy sources that can be regenerated.

14.Biomass produces methane gas that stinks but is fairly clean burning.

15.Any of:Walk, ride a bike, take the bus, vacation near home, turn off the lights when not in use, use efficient appliances,, put on a sweater, turn down the heater and air conditionerPRACTICE CONSERVATION!