Nature Awareness

Lesson 3

Can Sunlight Generate Heat?

-All of the Earth’s living material or ‘biomass’ exists in a thin layer around the surface of
the planet called the biosphere.
-It is a huge store of energy that is continually replenished by the Sun through photosynthesis.
-Biomass is any plant or animal matter, including plant and animal waste and human sewage.
-Energy crops are plants grown specifically for fuel.
How is it used to generate electricity?
http://www.eon-uk.com/EnergyExperience/859.htm 

Advantage

-It is renewable
-It is a carbon neutral source of energy
Disadvantage
-It is an expensive method of generating electricity

-Biomass power plants need to be built near a plentiful supply of biomass fuel.

What is Solar Energy?

-Solar energy is energy from the Sun
-The Sun gives off plenty of energy, which can be used to provide heat and to generate electricity.
-There are two kinds of solar panels: solar thermal panels, which heat water, and solar PV (photovoltaic) panels, which change light energy into electricity.
How PV Cells Work?

http://www.eon-uk.com/EnergyExperience/355.htm

Advantage

-it is renewable
-It does not produce any carbon dioxide (CO2), which contributes to the greenhouse effect.
-Energy is usually generated at or near to the location it will be used.This keeps transmission and distribution costs to an absolute minimum.
Disadvantage
-PV cells do not work so well when it is cloudy and do not work at night

-Solar power works better in hot places, so its use is therefore limited.

What is Geothermal Energy?

-Geothermal energy is a form of renewable energy that is not dependant on the Sun, but on heat that comes from deep below the surface of the Earth in the layer called the mantle.
How it is used to generate electricity?

http://www.eon-uk.com/EnergyExperience/861.htm

Advantages

-Geothermal energy does not produce any pollution.
-Running costs for a geothermal power station are very low.

Disadvantages

-It is difficult to find suitable sites to put a geothermal power station.
-If not carefully managed, a borehole can ‘run out of steam’ and may not be useable for several decades.
-Dangerous gases and minerals can come out of a borehole, which may be difficult to dispose of.