18.3 Solar & Wind Energy Flashcards
Harnessing the sun’s energy for one day would
result in enough energy to power humanity for 25 years
Passive Solar Energy:
Using sunlight directly without involving mechanical or electrical devices
Active Solar Energy:
Using technology to move or store the energy
EX. flat plate collector
Flat Plate Solar Collector:
Generally consisting of a black, heat-absorbing metal plate in a flat box with a glass cover. Sunlight passes through glass heating the metal plate, a tube of fluid then absorbs the plate’s heat and can then evenly distribute it in a building
2 functions of flat plate solar collectors
Heating water and air
Passive & active solar heating don’t generate
electrictity
Photovoltaic Cell (PV Cell)
converts solar energy directly into electricity by using the flow of elctrons from one plate to another
Places PV Cells are found
Watches, powerplants, calculators
Concentrated Solar power (CSP)
A technology that uses mirrors to focus sunlight in order to generate electricity
How a Tower Power CSP functions
hundreds of mirrors surrounding a Towe Power focus sunlight towards that power tower, heating a fluid that will produce steam, spinning a turnine
How much longer the sun will burn
4-5 billion more years
Percent by wich solar energy has grown since 1972 worldwide
28%
Solar power has a growth rate second to
wind power
Benefits of Solar Power
-safe
-0 pollution
-a single unit can last 25-30 years
-reduces dependence on powerplants
-helpful in developing nations
-consumers may lower their electric bill
Disadvantages Of Solar Power
-manufacturing of parts is only partially clean
-location similar to Seatle cannot rely on the sun
-investment in solar power is higher than FF but likely to fall
The world’s biggest leaders in wind turbine energy
US
China
Why is wind energy indirectly a form of solar energy
The sun unevenly heats the earth so warm air much move around since it wants to be balanced out, creating winds
Wind Farms:
Groups of wind turbines
Wind Turbines:
a device converting the wind’s kinetic energy into electrical energy
Reasoning for building turbines on the ocean
wind is usually 20% greater
The downside of offshore wind farms
higher maintenance is required yet, still more profitable
Benefits Of Wind Power
-no pollution
-under the best conditions highly efficient
-high startup cost yet less expensive whilst running
-can produce 23 times more energy than used
Disadvantages Of Wind Power
-we have no control over when the wind will occur
-disliked around communities
-kills large flying animals
Thermal mass examples
bricks, pavement
things absorbing heat
