1. Renewable Energy Resources

2. D8 D9 D25 D26
D8 - Describe the availability, current uses and environmental issues related to the use of fossil and nuclear fuels to produce electricity.
D9 - Describe the availability, current uses and environmental issues related to the use of hydrogen fuel cells, wind and solar energy to produce electricity.
D25 - Explain how land development, transportation options and consumption of resources may affect the environment.
D26 - Describe human efforts to reduce the consumption of raw materials and improve air and water quality.
Take a closer look at our conventional fuel resources (i.e., oil, natural gas, coal, and nuclear)

3. Many of our current energy sources are causing pollution
The problems ….
Many of our current energy sources are causing pollution
43% of energy in the US is wasted unnecessarily
What is nuclear energy?
In a nuclear fission reaction, neutrons split the nuclei of atoms such as uranium-235 and plutonium-239. In the process, energy (primarily in the form of high temperature heat) is released. In a nuclear reactor, the production of heat generated by this reaction is controlled and used to produce high pressure steam, which is in turn used to spin turbines that generate electricity.
Nuclear fission is basically the splitting of nuclei of certain isotopes with large mass numbers. Neutrons are fired at them, which causes them to split into lighter nuclei and to release single neutrons and energy. These single neutrons can in turn cause additional fission, but there has be enough single neutrons (critical mass) in order for the reaction to sustain itself.
If controllable, nuclear power can be an efficient source of power, but large government subsidies distort the true price of nuclear and the disposal of nuclear waste has proven to be an environmentalists nightmare. Disasters on the global scale, such as Chernobyl and Three Mile Island, also highlight the risk of this type of energy source.

4. Example 1… lighting choices

5. Example 2… Automobiles
Changes in required mpg fuel efficiency would help to reduce gasoline consumption
Minimum requirements by date
1974 – 12.9 mpg
mpg
2016 – 35.5 mpg

7. Efficiencies – these percentages show how much of energy taken in is actually used for the designated purpose

8. Some Ways to Improve Energy Efficiency
Insulate / Eliminate air leaks in homes / install high efficiency lighting
Purchasing more efficient appliances
Build efficient electric motors
Increasing fuel economy for all combustion engines

9. Characteristics of Renewable Resources
A Renewable Resource:
Replenishes very rapidly
Is in inexhaustible supply

10. Renewable Energy Resources
Solar—passive and active
Hydroelectric power
Wind generation
Biomass
Hydrogen Fuel Cell Power
Geothermal

11. Using Solar Energy to Provide Heat and Electricity
Solar energy originates as energy derived from the sun in the form of solar radiation.
This energy can be captured in passive or active systems (see image below).

12. Solar Energy PROS Fairly high energy acquisition, even on cloudy days
Quick installation
No CO2 emissions / low environmental impact
Installed system lasts years
CONS
Needs access to sun
Low efficiency
Requires an electricity storage system
Expensive

13. Hydropower
Hydropower is a method of producing electricity by harvesting the energy of moving water
Currently, this supplies …
50% of West Coast electricity
7% of US electricity
20% of World’s electricity

14. Hydropower Pros and Cons
More environmentally friendly than fossil fuels and
Reliable, stable and high efficiency
Does not create waste
CONS
High construction costs
Major environmental impacts

15. Environmental Effects of Hydropower
Pollution
Disruption of water flow
Loss of biodiversity
Invasive species

16. Producing Electricity from Wind
Wind energy is a form of energy conversion in which turbines convert the kinetic energy of wind into mechanical or electrical energy that can be used for power.
Historically, wind power in the form of windmills has been used for centuries for such tasks as grinding grain and pumping water.

17. Pros and Cons of Wind Power
Reduces greenhouse gas emissions
All the turbines need to be able to function is wind
It will also foster domestic economic growth.
Cons:
Land must be taken from its current uses to construct these turbines.
Wind energy is not always consistent
Blades of the turbines have in the past incidentally kill birds that get caught in their path.
Turbines require maintenance

18. Producing Energy from Biomass
Biomass energy is energy derived from plants or plant-derived materials. Biomass can be converted into biofuels for transportation, biopower for heat and electricity and bioproducts for making things such as plastics.
Examples of biomass energy sources include wood, ethanol derived from grains and methane gas emitted from landfills.

19. Pros and Cons of Biomass
1. Renewable - We will always have the sources of biomass such as crops, manure and garbage.
2. Carbon Neutral – The carbon in biomass is already part of the carbon cycle, so this does not add more carbon to the cycle.
3. Cost-Effective - Energy harnessed from biomass is inexpensive compared to coal and oil.
4. Abundant - Biomass is available over the world.
Cons:
1. Expensive - Extraction of biomasses can be expensive. In some areas, biomass projects may not be worth the price.
2. Requires Space - Big areas are needed for all the different processes that are required in harnessing energy from biomass.

20. Hydrogen Fuel Cell Power
A hydrogen fuel cell uses the chemical energy of hydrogen to cleanly and efficiently produce electricity with water and heat as byproducts.
Currently, this technology is being applied to automobiles

21. Hydrogen Fuel Cell Power
PROS
Less greenhouse emissions and lowered air pollution
Reduced oil dependence
CONS
Expensive
Fuel cell systems are not yet as reliable as internal combustion engines
There is not yet infrastructure in place to get hydrogen to consumers

22. Geothermal Energy
This term comes from the Greek roots geo, meaning earth, and thermos, meaning heat.
This energy comes from heat inside the Earth's crust. It's clean and sustainable

23. Pros and Cons of Geothermal Energy
1. Environmentally Friendly - There are a few polluting aspects of harnessing geothermal energy
2. Renewable - Geothermal reservoirs come from natural resources and are naturally replenished. Geothermal reservoirs will literally last billions of years.
3. Massive Potential - Worldwide energy consumption – about 15 terawatts (TW) – is not anywhere near the amount of energy stored in earth.
4. Stable - Geothermal energy is a reliable source of energy. We can predict the power output of a geothermal power plant with remarkable accuracy.
Cons:
1. Environmental Issues - There is an abundance of greenhouse gases below the surface of the earth that can be released.
2. Surface Instability (Earthquakes) - Construction of geothermal power plants can affect the stability of land.
3. Expensive - The exploration and drilling of new reservoirs come with a steep price tag (typically half the costs).
4. Location Specific - Good geothermal reservoirs are not present in every location.

24. Geothermal Reservoirs

25. Entering the Age of Decentralized Micropower
Our current system involves producing energy in large quantities at a few locations and moving it long distances.
A “decentralized micropower” system involved producing energy at more numerous smaller plants closer to where it will be used
Fig
p. 411

26. Creating a Sustainable Energy Future
Increase fuel efficiency standards for vehicle, appliances, buildings
Create tax and other financial incentives for energy efficiency
Subsidize renewable energy use, research and development
Internalize externalities for fossil fuels
By 2050:
Increase renewable energy to 50%
Cut coal use by 50%
Phase out nuclear altogether
What is nuclear energy?
In a nuclear fission reaction, neutrons split the nuclei of atoms such as uranium-235 and plutonium-239. In the process, energy (primarily in the form of high temperature heat) is released. In a nuclear reactor, the production of heat generated by this reaction is controlled and used to produce high pressure steam, which is in turn used to spin turbines that generate electricity.
Nuclear fission is basically the splitting of nuclei of certain isotopes with large mass numbers. Neutrons are fired at them, which causes them to split into lighter nuclei and to release single neutrons and energy. These single neutrons can in turn cause additional fission, but there has be enough single neutrons (critical mass) in order for the reaction to sustain itself.
If controllable, nuclear power can be an efficient source of power, but large government subsidies distort the true price of nuclear and the disposal of nuclear waste has proven to be an environmentalists nightmare. Disasters on the global scale, such as Chernobyl and Three Mile Island, also highlight the risk of this type of energy source.

27. Solutions: A Sustainable Energy Strategy