Environmental Science Chapter 18 Review Essay

Chapters 18-1 & 18-2 Review Section 1 Review – 1. List six forms of renewable energy, and compare the advantages and disadvantages of each. Pros: 1) Passive solar heating may hold a great advantage for a homeowner if there is reliable sunlight that is able to shine into the home and create warmth. Also, it will reduce energy bills in their liquid even when the sun is not shining. 3) Wind power is cheap, clean energy that is the average household. 2) Active solar heating systems have the advantage of storing heat in essentially free once the infrastructure is paid for. 4) Biomass fuel is in abundant supply and can convert waste into energy. 5) Hydroelectric energy may be expensive to build, but are inexpensive to operate. Unlike fossil fuel plants, hydroelectric dams do not release air pollutants into the atmosphere that cause acid precipitation. They also last longer than most other plants. 6) Geothermal energy is almost entirely emission free and can be built underground. Cons: 1) Passive solar heating may only be seen as an effective use of power if the climate is able to provide enough sunlight. 2) Active solar heating plans are expensive and in most areas, an active solar system will be unable to capture enough sunlight to replace the heating and electrical systems in a house. 3) Wind power can be a failed energy source, for wind is inconsistent, unsteady and unpredictable. 4) Biomass fuel is costly to produce and needs a substructure of fossil fuel for production and use. It can result in habitat loss, deforestation, and harmful air pollution. 5) Hydroelectric energy is directly related to how much water is available, thus potentially causing a drought. They also relate to interventions in nature due to damming of water, changed water flow and the construction of roads and power lines. 6) Geothermal power is also expensive to obtain and must be managed carefully so that it is not depleted . 2. Describe the differences between passive solar heating, active solar heating, and photovoltaic energy. Passive solar energy uses the sun’s energy to heat something directly while active solar heating and photovoltaic energy uses energy from the sun that is gathered by collectors. 3. Describe how hydroelectric energy, geothermal energy, and geothermal energy pumps work. Hydroelectric energy is produced by heating up water to produce steam, which then spins the turbines and generates electricity. Geothermal energy  is created when steam rises through a well and drives turbines, which generate electricity. The leftover liquid water is then pumped back into the hot rock. Geothermal energy pumps are used so when the ground is warmer, the heat is transferred from the ground to warm the house and when the ground is cool, heat is transferred from the house to the ground to cool the house. 4. Explain whether all renewable energy sources have their origin in energy from the sun. Only a small fraction of the sun’s energy reaches the Earth. However, this energy is enough to power the wind, plant growth, and the water cycle. So nearly all renewable energy comes directly or indirectly from the sun. Section 2 Review – 1. Describe three alternative energy technologies, and identify two ways that hydrogen could be used as fuel source in the future. Three examples of alternative energy technologies are tidal power, ocean thermal energy conversion, and solar chimneys. Tidal power is when the tide rises, water flows behind a dam and when the tide falls, the water is trapped behind the damn. When water in the reservoir is released, it turns a turbine that generates electricity. OTEC is when warm surface water is brought to a boil in a vacuum chamber. The boiling water produces steam to drive a turbine that generates electricity. Solar chimneys use the greenhouse effect to produce moving air that escapes through a central chimney where wind turbines make electricity. Hydrogen can be burned as fuel, for it does not contain carbon, so it does not release pollutants associated with burning fossil fuels and biomass. Hydrogen isotopes can also be used in a controlled nuclear fusion reaction. 2. List as many w ays as you can for individuals and communities to conserve energy. – Replacing light bulbs with new energy efficient models – Adjusting the temperature of your home while away or sleeping – Wash clothing with cold water – Install low-flow showerheads and faucets – Turning out lights in vacant rooms 3. Describe the difference between energy conservation and energy efficiency. Energy efficiency is the percentage of energy put into a system that does useful work while energy conservation means saving energy. 4. What factors influence a person’s choice to conserve energy? Factors that may influence a person’s choice to conserve energy are to help lower their energy bill and help the environment.