Solar Energy

Hunter and Chelsey

What can it be used for?

• The possibilities are limitless

• Heating/cooling

• Cooking

• Electricity

• Generates these in several different ways

vocabulary

• Superwindow

• Solar cell

• The sun

• Passive

• Active

• Nonimaging optical solar concentrator

• Heliostats

Solar tower

What is the renewability?

• Limitless

• The amount of solar energy receivable from the earth’s surface in one hour is enough to power the world for a year

How much does it cost?

• Depends on the method• Solar cells- low• Heliostats- ? Molten salt my lower costs• Thermal plants- high• Passive homes- low• Active homes- high• Nonimaging optical solar concentrators-

high

What are the positives?

• No CO2 emissions

• Investment recovery is quick

• Allows for “off the grid lifestyle”

• Concepts are easy to understand

• Little need for replacement for certain aspects of the technology

What are the negatives?

• Most of the technologies are expensive up front

• Making solar cells produces toxic chemicals

• Solar ovens take too long to cook things

• Easily foiled by clouds and/or bad weather

The science: generation

• Solar cells has a transparent skin that contains a semiconductor material. Sunlight energizes the delicious filling causing electrons to flow.

• Heliostats are towers with container filled with a heating agent at the top. Mirrors surrounding the structure heat the agent that is pumped down to heat water to produce electricity.

The science: generation cont.

• Solar ovens cook food by reflecting sunlight to a concentrated point and heating it up

• Passive homes use the sun to heat their home through “natural” methods

• Active homes use the sun to heat water which exchanges it with the house

The science: waste by-products

• The only waste by-products of solar energy are the ones from the production of solar cells such as certain heavy metals. After the use of the silicon it also must be disposed of as well

What’s holding it back nothing?

• Nothing • Every two years the number of solar cells

doubles• Third world countries that do not have

power grids have villages that have hot water due to inexpensive solar collectors

• Germany, China, and U.S. have projects in the works to drastically increase solar power by 2020

When will it be available?

• As costs go down and popularity goes up someday in the near future it may be possible to power your house with solar energy for $200-$300 flat.

Solar and carbon

• Solar has 0 carbon emissions and there for would have no affect on carbon sources and sinks. The affect of pollutants from solar cell production are, as of yet, undetermined.

Bibliography • Brown, Lester R. Plan B 3. 0 : Mobilizing to Save Civilization. Boston: W. W. Norton & Company,

Incorporated, 2008. 246-52.

• Miller, G. Tyler. Living in the Environment. 12th ed. Vol. 1. Belmont: Brooks/Cole, 2001. 370-78.

• Dunbar, Birnie, III P. "Different Types of Solar Cell." Different Types of Solar Cell. 2006. Rutgers University. 6 Dec. 2008 <http://www.solar.rutgers.edu/differenttypes.htm>.

• McGrath, Jane.  "What is thermal technology?."  13 May 2008.  HowStuffWorks.com. <http://science.howstuffworks.com/thermal-technology.htm>  08 December 2008.

• Aldous, Scott.  "How Solar Cells Work."  01 April 2000.  HowStuffWorks.com. <http://science.howstuffworks.com/solar-cell.htm>  08 December 2008.

• "solar energy." Encyclopædia Britannica. 2008. Encyclopædia Britannica Online. 08 Dec. 2008 <http://www.britannica.com/EBchecked/topic/552905/solar-energy>.

• Bullis, Kevin. "Intensifying the Sun." Technology Review 111 (2008). Sept. 2008. MAS Ultra - School Edition. EBSCOhost. 6 Dec. 2008 <http://search.ebscohost.com/login.aspx?direct=true&db=ulh&an=34598421&site=src-live>.