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Sunpeak USA, Inc.

SUNPEAK USA Inc.

1. Deciding the Direction and Angle of Installation.

2. What is Solar Insolation?

1. Deciding the Direction and Angle of Installation.

The angle and direction of installation is of great importance as it will affect the efficiency of the solar collector. Naturally, you want the collector to receive the maximum amount of sunlight each day and throughout the year. If you are in the Northern Hemisphere (USA) then the collector should face South and if you are in the Southern Hemisphere then the collector should face North. See diagram below.

Insolation diagram

 

The angle at which you mount the collector should roughly correspond to the latitude of your location. For example:

- Chicago, Illinois has a latitude of 41 degrees North.  The collector should face South at a 41 degree angle approximately.

- Jacksonville, Florida has a latitude of 30 degrees North.  The collector should face South at a 30 degree angle approximately.

- Sao Paulo, Brazil has a latitude of 23 degrees South.  The collector should face North at a 23 degree angle approximately.

For a list of US cities latitudes see chart below or go to http://www.infoplease.com/ipa/A0001796.html

If your roof angle is within +/-10°of your desired angle, you can just mount the solar collector flush against the roof surface without it affecting the efficiency of your unit.

How to prevent excessive summer heat output:

Adjusting the angle of the collector can help to reduce summer heat output. By increasing the vertical angle of the collector by about 15 to 20 o more than the location's latitude (i.e. 45o instead of 30o), greater winter performance will be experienced. This is because the collector is "facing" the sun as the sun is lower in the winter and higher in the summer. During the summer months, the collector will be slightly less efficient and as such, heat output will be reduced as the collector is not "facing" the sun. This simple solution alone can reduce peak summer output considerably, thus reducing problems associated with excessive summer heat production.  All SUNPEAK USA Inc. package products come with a heat dissipater (radiator safety feature), that prevents the overheating problem.   

Please note: For the GTC solar panels, optimal heat pipe performance is achieved in the angle range of 20-70o. Although your location may have a latitude of less than 20o, this basic installation guidelines should be followed.  Horizontal angles of +5o are acceptable and may be appropriate.

2. What is Solar Insolation?

Insolation is the amount of electromagnetic energy (solar radiation) coming in contact with the surface of the earth. Basically, that means how much sunlight is shining down on us. We use this number to help us decide the size of your unit and energy savings.  The higher the number the more solar radiation your collectors will receive.  The chart below gives each state and a city’s insolation monthly and yearly average.  A high value such as Hawaii 5.96 tells you that the unit will be very efficient.

This is the angle that the solar collector should be tilted to.

i.e., AL= 33 degrees south tilt

FL = 25 degree south    

This number is the solar insolation level in your area and is used in our calculations to obtain the size of your unit and rate of return.


State

City

Latitude

Longitude

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year Avg.

AL

Birmingham

33' 34" N

86' 45" W

2.29

3.31

4.04

5.14

5.92

5.98

5.81

5.7

4.8

3.93

2.96

2.25

4.34

AK

Anchorage

61' 10" N

150' 1" W

0.21

0.76

1.68

3.12

3.98

4.58

4.25

3.16

1.98

0.98

0.37

0.12

2.09

AR

Little Rock

32' 25"N

94' 44" W

2.36

3.39

4.01

5.32

5.71

6.19

6.15

5.85

5.25

4.17

2.95

2.25

4.46

AZ

Phoenix

33' 26"N

112' 1" W

3.25

4.41

5.17

6.76

7.42

7.7

6.99

6.11

6.02

4.44

3.52

2.75

5.38

CA

Los Angeles

34' N

118' W

3.09

4.25

5.09

6.58

7.29

7.62

7.45

6.72

6.11

4.42

3.43

2.72

5.40

CA

San Francisco

38' 31" N

121' 30" W

2.35

3.33

4.42

5.95

6.84

7.39

7.55

6.51

5.75

3.92

2.65

2.06

4.89

CO

Denver

39' 45" N

104' 52" W

2.25

3.2

4.32

5.61

6.11

6.71

6.5

5.86

5.47

4.01

2.59

1.98

4.55

CT

Hartford

41' 44" N

72' 39" W

1.7

2.43

3.48

4.07

5.14

5.58

5.38

5.04

4.13

2.91

1.81

1.42

3.59

DE

Dover

39' 8"  N

75' 28" W

1.85

2.62

3.6

4.33

5.44

5.91

5.64

5.3

4.38

3.23

2.21

1.66

3.84

FL

Miami

25' 48" N

80' 16" W

3.72

4.61

5.42

6.4

6.61

6.29

6.26

6.08

5.47

4.84

3.96

3.46

5.26

GA

Atlanta

33' 39" N

84' 26" W

2.31

3.37

4.08

5.2

6.02

6.01

5.81

5.59

4.76

3.95

2.98

2.33

4.37

HI

Honolulu

21' 20" N

157' 55" W

4.38

5.15

5.99

6.69

7.05

7.48

7.37

7.07

6.51

5.46

4.41

4.01

5.96

IA

Dubuque

42' 24" N

90' 42" W

1.64

2.58

3.34

4.57

5.54

6.06

5.81

5.26

4.33

3.03

1.72

1.35

3.77

ID

Boise

43' 34" N

116' 13" W

1.73

2.72

3.77

5.22

5.9

6.57

7.17

6.12

5.28

3.29

1.74

1.46

4.24

IN

Indianapolis

39' 44" N

86' 17" W

1.67

2.59

3.28

4.67

5.46

6.11

5.79

5.37

4.76

3.33

1.97

1.46

3.87

IL

Chicago

41' 53" N

87' 38" W

1.5

2.45

3.2

4.48

5.56

6.07

5.68

5.27

4.51

3.07

1.69

1.26

3.72

KS

Kansas City

39' 12" N

94' 36" W

2.06

2.89

3.62

4.92

5.58

6.17

6.21

5.59

4.9

3.49

2.2

1.75

4.11

KY

Louisville

38' 11" N

85' 44" W

1.71

2.65

3.32

4.73

5.38

6.08

5.79

5.35

4.8

3.42

2.1

1.56

3.9

LA

New Orleans

29' 37" N

90' 5" W

2.64

3.73

4.67

5.8

6.6

6.15

6.09

5.7

5.13

4.48

3.49

2.68

4.76

MA

Boston

42' 22" N

71' 2" W

1.66

2.5

3.51

4.13

5.11

5.47

5.44

5.05

4.12

2.84

1.74

1.4

3.58

MD

Annapolis

38' 35" N

76' 21" W

1.96

2.8

3.71

4.55

5.54

6.03

5.77

5.34

4.48

3.4

2.37

1.81

3.98

ME

Portland

45' 36" N

122' 36" W

1.38

2.33

3.49

4.57

5.46

6.09

6.64

5.78

4.8

2.79

1.41

1.1

3.82

MI

Detroit

42' 25" N

83' 1" W

1.43

2.33

3.19

4.34

5.44

5.98

5.64

4.99

4.25

2.73

1.52

1.14

3.58

MO

St. Louis

38' 45" N

90' 23" W

2.02

2.82

3.52

4.97

5.56

6.21

6.05

5.63

4.91

3.55

2.21

1.73

4.09

MN

Minneapolis

44' 53" N

93' 13" W

1.6

2.61

3.3

4.55

5.44

5.86

5.77

5.12

4.12

2.9

1.62

1.34

3.68

MS

Jackson

42' 16" N

84' 28" W

1.47

2.41

3.22

4.33

5.46

5.93

5.57

4.99

4.3

2.78

1.55

1.17

3.59

MT

Billings

45' 48" N

108' 32" W

1.55

2.57

3.52

4.82

5.63

6.45

6.39

5.75

4.67

3.19

1.77

1.3

3.96

MT

Great Falls

43' 33" N

96' 42" W

1.3

2.36

3.41

4.84

5.56

6.18

6.44

5.53

4.4

2.9

1.53

1.11

3.79

NC

Charlotte

35' 13" N

80' 56" W

2.22

3.17

3.95

4.98

5.8

6.01

5.76

5.27

4.58

3.75

2.76

2.21

4.2

ND

Fargo

46' 54" N

96' 48" W

1.44

2.39

3.36

4.79

5.62

5.82

5.94

5.14

4.01

2.83

1.59

1.31

3.68

NE

Omaha

41' 18" N

95' 54" W

1.92

2.76

3.45

4.74

5.6

6.14

6.11

5.46

4.74

3.34

2

1.57

3.98

NH

Manchester

42' 56" N

71' 26" W

1.66

2.5

3.51

4.13

5.11

5.47

5.44

5.05

4.12

2.84

1.74

1.4

3.58

NJ

Trenton

40' 13" N

74' 46" W

1.71

2.39

3.43

4.04

5.26

5.67

5.39

5.14

4.18

3

1.98

1.48

3.63

NM

Albuquerque

35' 3"   N

106' 37" W

2.92

3.97

4.92

6.3

6.68

6.94

6.66

5.8

5.68

4.18

3.16

2.5

4.97

NV

Las Vegas

36' 18" N

115' 16" W

3.02

4.13

5.05

6.57

7.25

7.69

7.37

6.42

6.08

4.26

3.18

2.6

5.3

NY

New York

41' N

74' W

1.67

2.37

3.41

3.93

5.11

5.48

5.26

5.01

4.05

2.85

1.82

1.4

3.53

OH

Columbus

39' 16" N

85' 54" W

1.64

2.57

3.26

4.63

5.4

6.08

5.73

5.29

4.74

3.29

1.96

1.45

3.83

OK

Tulsa

36' 12" N

95' 54" W

2.33

3.22

3.9

5.25

5.58

6.32

6.4

5.8

5.08

3.8

2.62

2.06

4.36

OR

Portland

45' 32" N

122' 40" W

1.38

2.33

3.49

4.57

5.46

6.09

6.64

5.78

4.8

2.79

1.41

1.1

3.82

PA

Philadelphia

39' 53" N

75' 15" W

1.85

2.62

3.6

4.33

5.44

5.91

5.64

5.3

4.38

3.23

2.21

1.66

3.84

PA

Pittsburgh

40' 27" N

79' 57" W

1.59

2.4

3.26

4.07

5.05

5.53

5.27

4.94

4.05

2.88

1.86

1.41

3.53

RI

Providence

41' 44" N

71' 26" W

1.7

2.46

3.53

4.2

5.17

5.67

5.48

5.08

4.21

2.97

1.8

1.43

3.64

SC

Columbia

38' 58" N

92' 22" W

2.14

2.91

3.62

5.03

5.56

6.22

6.13

5.64

4.95

3.57

2.25

1.82

4.15

SD

Sioux Falls

45' 27" N

98' 25" W

1.72

2.71

3.31

4.65

5.61

6.1

6.04

5.42

4.47

3.2

1.78

1.43

3.87

TN

Nashville

36' 7"   N

86' 41" W

1.94

2.9

3.54

4.76

5.57

5.9

5.86

5.62

4.63

3.53

2.45

1.82

4.04

TX

San Antonio

29' 32" N

98' 28" W

2.57

3.7

4.43

5.54

5.94

6.62

6.49

6.28

5.7

4.67

3.43

2.62

4.83

TX

Houston

29' 59" N

95' 22" W

2.47

3.5

4.4

5.59

6.03

6.45

6.36

6.07

5.46

4.61

3.3

2.44

4.72

UT

Salt LakeCity

40' 46" N

111" 52"W

2.23

3.15

4.09

5.57

6.26

6.98

6.86

5.98

5.39

3.68

2.29

1.97

4.53

VA

Washington

38' 51" N

77' 2" W

1.95

2.8

3.66

4.46

5.42

5.88

5.63

5.22

4.38

3.36

2.34

1.79

3.9

VT

Montpelier

44' 16" N

72' 35" W

1.58

2.54

3.5

4.05

5

5.24

5.37

4.92

3.79

2.46

1.52

1.28

3.43

WA

Seattle

47' 32" N

122' 18" W

1.14

2.04

3.23

4.26

5.19

5.75

6.27

5.46

4.43

2.5

1.21

0.9

3.53

WI

Milwaukee

42' 57" N

87' 54" W

1.43

2.41

3.29

4.48

5.6

6.09

5.74

5.21

4.34

2.9

1.6

1.2

3.69

WV

Charleston

38' 22" N

81' 36" W

1.75

2.64

3.34

4.26

5.2

5.67

5.49

5.19

4.26

3.19

2.15

1.62

3.73

WY

Casper

42' 55" N

106' 28" W

1.93

2.8

3.79

5.13

5.9

6.68

6.5

5.9

5.13

3.59

2.06

1.65

4.25

                                  

 

© 2010 SUNPEAK USA Inc.

Related resources



For a list of US cities latitudes see chart below or go to http://www.infoplease.com/ipa/A0001796.html