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Flashcards in Solar Deck (98)
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1

What is the STC wattage m2

1000 w square meters

2

What is STC degrees

25 degrees is what ?

3

Air mass for STC is

1.5

4

A string inverter works in a ? Circuit

Series

5

A micro inverter works in a ? Circuit

Parallel circuit

6

What is the effeciency of string invertor

They take the energy from the lowest performing solar panel and use that for all panels. So if a tree shades one panel 20% they all work at 20%

7

What is PPA

Power purchase agreement where you lease the panels and it goes on your roof. Price is lower but you never own panels so never get to 0

8

Remote net metering is what

Where you own two buildings with only one having solar so you offset the extra made to the building without

9

What does an inverter do

Changes current from DC into AC for the house

10

What does a charge controller do

Makes sure batteries don’t over or under charge

11

NEC

National electric code

12

What is article 690

The guildlines for solar

13

What is ballasted rack

Solar elevated on a angle good for flat roof

14

What is independent power producer

Someone who generally creates over 100/110 percent of their needs. Not allowed

15

How much can a panel loose when installed

10/20 percent. Power loses from loose wiring inverter dust temperature

16

What and who created photovoltaic effect ?

Alexandre bacquerel 1839 a process that produced voltage or current when exposed to light or radiant energy.

17

When was the first solar install

1883 in nyc Charles Fritta had effeciency of 1/2%

18

Who created the first viable solar panel

Bell labs 1954 10 perfect efficiency

19

How many solar satellites in 1970

1000

20

What was solar per watt in 1976 and what is average today

Cost was $100 PW and US average is $3/4 PW

21

How much will solar grow annually

0.16

22

What is gallium arsenide

The newest in solar cells out perform silicon Max out put 28 watts

23

What is solar constant

Solar constant is the total radiation received from the sun per unit of time and area. The value of the solar constant is 1.366 kilowatts per square meter

24

Electron

Carries a charge and smallest amount of electrical charge possible to have.

25

What is atomic model

Consist of atomic nucleus and electron shell. Electrons move around the nucleus like planets. Electrons are charged negatively while nucleus is composed of uncharged neutrons and positively charge protons. It’s overall charge it’s positive equal electrons and protons.

26

Beam radiation

When the solar panels face exactly towards the sun

27

Diffuse radiation

Diffuse radiation is solar radiation reaching earth’s surface after having been scattered from the direct solar beam by molecules or suspensoids in the atmosphere.

28

Insolation

The total amount of radiation emitted from sun that you can use for solar cells

29

Heliostat

When you follow or track facing directly to sun

30

When you follow or track facing directly to sun

A way to offset change in seasons to get most beam radiation from the sun

31

A way to offset change in seasons to get most beam radiation from the sun

Add or subtract 15 % degree offset to the latitude to accommodate for winter or summer

32

Azimuth

The compass angel as the sun moves East to west solar noon is consider azimuth angle of zero -90 to the East +90 to the west

33

Zenith

This is angle of sun looking up 90% at midday sunrise and sunset 0%

34

Formula to calculate system size

(Energy demand/annual full sun hours)/efficiency = PV system size

35

Solar insulation map

Shows the daily and annual averages for sunlight

36

which is incident light?

a light that falls on a subject (not what is reflected by it)

37

How much and where is Silicon

Very common in crust of earth. 20% of crust is silicon

38

Pauli exclusion principle

Electrons have 4 quantum numbers to fully describe them in an atom. No two electrons can have the same 4 quantum numbers in an atom meaning they repel each other and must move in opposite direction.

39

PIN structure

Positive Intrinsic Negative

40

What is doping

Adding impurities to change resistivity

41

Open circuit

Voc - A circuit that is open it has a break current won’t flow

42

Closed circuit

Switch closed current will flow

43

Short circuit

No resistance is high current

44

Pm

Maximum power

45

What does photovoltaic mean

Photo is light voltaic is electricity

46

PSH

Peak sun hours

47

Solar attenuation

The loss of solar irradiance as it passes through the atmosphere

48

When your modules are in series you increase by

By voltage

49

When your modules are in parallel you increase by

Currents

50

What is an array ?

More than one module put together

51

What is IV curve

V = volts I = current

52

What is Isc

short circuit current

53

What is PV curve

P = power V = volts

54

What is Imp

Maximum power current

55

Losses in an inverter are from

Heat

56

Vmp

Max power voltage

57

What does IV curve calculate

The max power point

58

To calculate max power point you need

Find product of Voc and Isc

59

MPPT

Maximum power point tracking charge controller l. Best on market. Converts high voltage produced from solar panel to lower voltage neccasry for battery

60

Shunt controller is ?

Simplest of charge controllers on off

61

PWM Pulse width modulation

Changes the charge depending on the load. Works 25% 50% 75%

62

Whenever there is resistance it creates

Heat

63

AHJ

Authorities having jurisdiction

64

How much is a megawatt

1000 kilowatts

65

VLSI

Very large scale integrated circuit

66

Anti islanding

Protection to shut of power going back to the grid if there is a failure or outage in grid

67

In an inverter heat creates what ?

Short circuit and damage to system

68

In an inverter what cables do you want

Short and think

69

Power optimizer

Optimizers the dc power as dc electricity to the battery from an array in a series.

70

Square wave

It’s when you have square waves that create harmonica and aren’t good for anything as it’s digital

71

Ohms law

Current goes up volts go up v = IR

72

Good conductor has what resistance

Low

73

Balance of system

BOS -Everything but the solar panels.

74

What is deep cycle batteries

Typically lead acid, generally used for small systems last 5/10 years and reclaim about 80% of energy powered into them

75

What is frequency of ac cycles

60 hertz or 60 cycles per second

76

Thermodynamics

Heat transmitted by Conduction Convection Radiation

77

What is the first Law of thermodynamics

Law of Conservation of Energy Energy can’t be created Can’t be destroyed Can’t be changed from one form to another Energy is conserved

78

2nd law of thermodynamics

The second law of thermodynamics states that the entropy of any isolated system always increases Meaning Perpetual motion machine isnt possible Some energy is wasted. Some energy is lost to another form

79

What kind of conductors should you use

Use conductors with least amount of resistance Large gauge cables

80

Energy balance

Energy supplies equal to energy used by device

81

Energy audit

App house hold load in watts Multiply by 1.25 for energy lost

82

Wp

Peak watts

83

What’s the average cost of solar installed

$20, 000 without rebates or credits

84

What is the potential increase in value to home for adding solar

$15 000

85

How much has the cost of solar dropped in last 5 years

0.2

86

what is PPW

Price per watt

87

What is a gigawatt and how much can it power

A gigawatt is one billion watts. It would power 725,000 homes and is more power produced than a conventional power plant

88

In the times of Carona, 3 reasons why solar will grow

- pollution reduction, people see the difference with air quality - the pandemic has us thinking globally, solar is healthier for all - security. Being able to take care of a fear of energy security in a crisis

89

agrivoltaic

Mixing of farm and solar

90

Mixing of farm and solar

What is a negawatt

91

What is a negawatt

A unit of energy saved as a result of conserving

92

DR

What happened to Albert Einstein in 1920 and prize?

93

What happened to Albert Einstein in 1920 and prize?

In 1921 he won Nobel prize for physics explaining the photovoltaic effect

94

What is albedo

The reflection of a surface.

95

What are bifacial solar panels and why are they good

Bifacial solar panels expose both the front and back of solar panels. Unlike mono facial panels, They take in reflection from underneath so they can take in the roof reflection, snow, sand in desert. from the ground. Some manufacturers say up too 30% increase in production.

96

Distributed solar

Solar that is produced and consumed close to each other

97

STC

Standard test conditions

98

How much energy in watts does an average home use?

Around 11 000 kilowatts per year 900 per month KWh