kidzsearch.com > wiki   Explore:images videos games

Solar energy

(Redirected from Solar power)
At the equator, the Sun provides approximately 1000 watts per square meter on Earth's surface.
The top diagram shows how the strength of sunlight is less nearer the Earth's poles. The lower map shows how much solar energy hits the Earth's surface after clouds and dust have reflected and absorbed some solar energy.

Solar energy is energy that is present in sunlight. It has been used for thousands of years in many different ways by people all over the world. As well as its traditional human uses in heating, cooking, and drying, it is used today to make electricity where other power supplies are absent, such as in remote places and in space. It is becoming cheaper to make electricity from solar energy and in many situations it is now competitive with energy from coal or oil.

Energy use

Solar energy is used today in a number of ways:

Energy from the Sun

After passing through the Earth's atmosphere, most of the Sun's energy is in the form of visible light and infrared light radiation. Plants convert the energy in sunlight into chemical energy (sugars and starches) through the process of photosynthesis. Humans regularly use this store of energy in various ways, as when they burn wood or fossil fuels, or when simply eating plants, fish and animals.

Solar radiation reaches the Earth's upper Earth's atmosphere with the power of 1366 watts per square meter (W/m2). Since the Earth is round, the surface nearer its poles is angled away from the sun and receives much less solar energy than the surface nearer the equator.

At present, solar cell panels convert, at best, about 15% of sunlight hitting them into electricity.[1] The dark disks in the third diagram on the right are imaginary examples of the amount of land that, if covered with 8% efficient solar panels, would produce slightly more energy in the form of electricity than the world needed in 2003. [2]

Types of technologies

Solar energy absorbing panels on the sound barrier next to the Munich airport.

Many technologies have been developed to make use of solar radiation. Some of these technologies make direct use of the solar energy (e.g. to provide light, heat, etc.), while others produce electricity.

Solar power plants

Solar power plants convert sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP). Concentrated solar power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. Photovoltaics converts light into electric current using the photoelectric effect.[3]

Photovoltaics

World's largest photovoltaic power stations
Photovoltaic power station Country Site co-ordinates Nominal
power
Production
(Annual
GW·h)
Notes and references
Topaz Solar Farm[4] USA 35°23′N 120°4′W﻿ / ﻿35.383°N 120.067°W 500 installed capacity as of June 2014.
Desert Sunlight Solar Farm[5] USA 33°49′33″N 115°24′08″W﻿ / ﻿33.82583°N 115.40222°W 500 Commissioned since November 2013 toward final capacity 550 MW
Longyangxia Dam Solar Park[6] China 36°07′20″N 100°55′06″E﻿ / ﻿36.12222°N 100.91833°E 320 Completed December 2013
Solar Star I and II[7] USA 309 Under construction, 579MW when completed[8]
California Valley Solar Ranch[9] USA 35°20′N 119°55′W﻿ / ﻿35.333°N 119.917°W 292[10][11] 399 First 130MW connected Feb 2013.[12]
Agua Caliente Solar Project[13] USA 32°57.2′N 113°29.4′W﻿ / ﻿32.9533°N 113.49°W 290[14][15] 626 completed April 2014[16]
Antelope Valley Solar Ranch[13][17][18] USA 34°46′N 118°25′W﻿ / ﻿34.76667°N 118.41667°W 266[19] 230 MWAC. Has received government loan guarantee

Rank

View of Ivanpah Solar Electric Generating System from Yates Well Road, San Bernardino County, California. The Clark Mountain Range can be seen in the distance.
! Station Country Location Capacity (MW) Ref
1 Ivanpah  United States 35°34′N 115°28′W﻿ / ﻿35.567°N 115.467°W 377 [20]
2 SEGS  United States 35°01′54″N 117°20′53″W﻿ / ﻿35.03167°N 117.34806°W 354 [21]
3 Solana  United States 32°55′N 112°58′W﻿ / ﻿32.917°N 112.967°W 280 [22]
4 Genesis  United States 33°38′38″N 114°59′17″W﻿ / ﻿33.64389°N 114.98806°W 250 [23]
5 Solaben  Spain 39°13′29″N 5°23′26″W﻿ / ﻿39.22472°N 5.39056°W 200
6 Solnova  Spain 37°25′00″N 06°17′20″W﻿ / ﻿37.4166667°N 6.28889°W 150
6 Andasol  Spain 37°13′43″N 03°04′07″W﻿ / ﻿37.22861°N 3.06861°W 150 [24][25]
6 Extresol  Spain 38°39′N 6°44′W﻿ / ﻿38.65°N 6.733°W 150 [26][27]
9 Palma del Rio  Spain 37°38′N 5°15′W﻿ / ﻿37.633°N 5.25°W 100 [26]
9 Manchasol  Spain 39°11′N 3°18′W﻿ / ﻿39.183°N 3.3°W 100 [26]
9 Valle  Spain 36°39′N 5°50′W﻿ / ﻿36.65°N 5.833°W 100 [26][28]

Solar cooking

Solar cooking

Solar cooking uses the sun as the source of energy instead of standard cooking fuels such as charcoal, coal or gas. Solar cookers are an inexpensive and environmentally sound alternative to traditional ovens. They are becoming widely used in areas of the developing world where deforestation is an issue, financial resources to purchase fuel are limited, and where open flames would pose a serious risk to people and the environment.

Solar heating

House with solar panels for heating and other needs in Jablunkov, Czech Republic.
The sun may be used to heat water instead of electricity or gas. There are two basic types of active solar heating systems based on the type of fluid — either liquid or air — that is heated in the solar energy collectors. (The collector is the device in which a fluid is heated by the sun.)

Liquid-based systems heat water or an antifreeze solution in a "hydronic" collector, whereas air-based systems heat air in an "air collector."[29] Both air and liquid systems can supplement forced air systems.

Solar cells

Photo of 4 inch by 4 inch cell.

Solar cells can be used to generate electricity from sunlight. It is a device that converts light energy into electrical energy. Sometimes the term solar cell is reserved for devices intended specifically to capture energy from sunlight, while the term photovoltaic cell is used when the light source is unspecified.

Solar cells have many applications. They have long been used in situations where electrical power from the grid is unavailable, such as in remote area power systems, Earth-orbiting satellites and space probes, consumer systems, e.g. handheld calculators or wrist watches, remote radiotelephones and water pumping applications.

References

1. A solar panel in the contiguous United States on average delivers 19 to 56 W/m² or 0.45 - 1.35 (kW·h/m²)/day."us_pv_annual_may2004.jpg". National Renewable Energy Laboratory, US. Retrieved 2006-09-04.
2. International Energy Agency - Homepage
3. Technologies: From silicon to the solar cell.
4. The Tribune: California Valley's Topaz Solar Farm now producing electricity
5. Cite error: Invalid <ref> tag; no text was provided for refs named des.
6. SolarServer: CPI completes massive hybrid solar PV/hydro plant in Western China
7. Solar Star Project, Japan DG Demand Drive SunPower's Q3, Forbes, 10/31/2014
8. [1]
9. Energy Division Resolution E-4229
10. U.S. Solar Market Trends 2013, IREC, July 2014
11. Meza, Edgar (27 June 2013). "NRG Energy completes 250 MW California Valley Solar Ranch". Solar Energy Industry Association. Retrieved 5 July 2013.
12. "130MW energized". California Valley Solar Ranch. Retrieved Feb 2013.
13. RPS Project Status Table - February Update
14. World's Largest Operational Solar PV Project, Agua Caliente, Achieves 250 Megawatts of Grid-Connected Power
15. World’s Biggest Solar PV Plant a Feather in DOE’s Cap, Pete Danko, greentechmedia, May 2, 2014
16. "AV Solar Ranch One". NextLight Renewable Power LLC. 2009. Retrieved 2009-06-06.
17. Project Overview
18. Hill, Joshua (22 Feb 2013). "Antelope Valley Solar Ranch One Achieves 100 Megawatt Milestone". Clean Technica. Retrieved Feb 2013.
19. SEGS Power Stations, retrieved 2010-03-20
20. Abengoa Solar: Abengoa’s Solana, the US’s first large-scale solar plant with thermal energy storage system, begins commercial operation
21. CSP World
22. Andasol Solar Power Station, retrieved 2010-03-20
23. ACS LAUNCHES THE OPERATION PHASE OF ITS THIRD DISPATCHABLE 50 MW THERMAL POWER PLANT IN SPAIN, EXTRESOL-1
24. VALLE 1 and VALLE 2
25. Active Solar Heating