Renewable Energy Part I: SOLAR
Warm-up • Draw an image of what solar energy looks like. How do you think solar energy works? • What are some ways in that you can use solar energy at home? Draw from the energy efficient homes that we discussed earlier in class.
IMAGE 1 IMAGE 2
Active Solar Passive solar
Solar Energy Passive Solar
Passive Solar • Absorbs and stores heat from the sun directly within a structure without the need for pumps to distribute the heat.
Pros and Cons of Passive Solar? Advantages Disadvantages Initial cost is high Sun could be blocked by other structures May be unattractive Need access to sun for it to work • Energy is free • Net energy moderate • No CO2 emissions • Low air and water pollution • Low land disturbance
Cooling houses naturally • Insulation • Take advantage of breezes • Shading them • Having light colored or green roofs
Solar Energy Active Solar
Active Solar • Converts solar energy into electricity
Photovoltaic Cells • Made out of semiconductors
PV Cells • Solar cells can be used in rural villages with ample sunlight who are not connected to an electrical grid.
Pros and Cons of Active Solar Advantages Disadvantages Low efficiency High costs Back up system needed High land use May disturb desert areas • No CO2 emissions • Not as bad environmental impact as other sources • Fast construction
Discussion • Should the world greatly increase its dependence on solar cells? How about California, specifically? Explain your reasoning.
Solar Pizza Box Oven Passive? or Active?
Next Class: We will building our own solar pizza box oven!