ENVIRONMENTAL SCIENCE 101
ASSIGNMENT #8; DUE: March 28, 2013
1. Contrast passive and active solar heating. Describe how each works, and give examples of each. (6 points) Passive solar heating is a type of construction used on building for example that doesn’t use electronic devices to collect and take advantage of the sun’s energy. These types of buildings are constructed to take advantage of the sun’s solar heat in the winter and to reject it in the summer. They might do things such as plant a large tree in front of the sun-facing side of the house so that in the summer the tree shades the house from the sun and in the winter when all its leaves have fallen, the house can then absorb the sun’s heat better. Active solar heating is when external energy sources are used to absorb the sun’s heat energy. This can be done through the installation and use of electric solar panels for example.
2. Define the photoelectric effect. Explain how photovoltaic (PV) cells function and are used. (6 points) This effect occurs when solids, liquids or gases absorb light energy thus emitting some electrons. These cells can convert sunlight directly into energy by absorbing some of the energy through semiconductors which allows some electrons to get free and flow around, transferring their energy into electricity.
3. Describe several environmental and economic advantages of solar power. What are some disadvantages? (6 points) Advantages of solar power include no carbon or toxic gas emissions occur, it is a noiseless process, is a completely renewable resource, it is cheaper in the long run and solar panels for example require little upkeep. Some disadvantages are that solar panels can be very expensive when you first buy them and on cloudy or rainy days, not very much sunlight can be harnessed meaning you may still have to rely on other forms of electricity.
4. How do modern wind turbines...