Comparisons for 16 vs 20 citi clu048 3000k 1818's below for a 4x8, or similar
@2Ton. You could do half of this
@mo841
1818 3000K80Min 16 COBS @1400 mA ON 5.88 PROFILE HEATSINK
32 SQ.FT. CANOPY 94% EFFICIENT DRIVER @13 CENTS PER KWH
Total power watts at the wall: 1212.94
Cobs power watts: 1140.16
Total voltage forward: 814.40
Total lumens: 160423.06
Total PAR watts assuming 10% loss: 440.19
Total PPF: 2377.00
PPFD based on canopy area: 799.56
PAR watts per sq.ft.: 13.76
Cob efficiency: 42.90%
Power watts per sq.ft.: 35.63
Voltage forward per cob: 50.90
Lumens per watt: 140.70
Heatsink riser thickness / number of fins / fin's length: 0.27in/14/1.0in
Heatsink area per inch: 260.01 cm^2
Total heat watts: 649.89
umol/s/W: 2.08 LER: 328.00 QER: 4.86
Heatsink length passive cooling @120cm^2/heatwatt: 300 inches
Heatsink length active cooling @40cm^2/heatwatt: 100 inches
COB cost dollar per PAR watt: $0.84
Electric cost
@12/12 in 30 days: $56.77
Electric cost @18/6 in 30 days: $85.15
Cost per cob: $23.0
Heatsink cost per inch cut: $1.74
Total cobs cost: $368.0
Total heatsink passive cooling cost: $522.00
Total heatsink active cooling cost: $174.00
1818 3000K80Min 20 COBS @1400 mA ON 5.88 PROFILE HEATSINK
32 SQ.FT. CANOPY 94% EFFICIENT DRIVER @13 CENTS PER KWH
Total power watts at the wall: 1516.17
Cobs power watts: 1425.20
Total voltage forward: 1018.00
Total lumens: 200528.83
Total PAR watts assuming 10% loss: 550.23
Total PPF: 2971.25
PPFD based on canopy area: 999.45
PAR watts per sq.ft.: 17.19
Cob efficiency: 42.90%
Power watts per sq.ft.: 44.54
Voltage forward per cob: 50.90
Lumens per watt: 140.70
Heatsink riser thickness / number of fins / fin's length: 0.27in/14/1.0in
Heatsink area per inch: 260.01 cm^2
Total heat watts: 812.36
umol/s/W: 2.08 LER: 328.00 QER: 4.86
Heatsink length passive cooling @120cm^2/heatwatt: 375 inches
Heatsink length active cooling @40cm^2/heatwatt: 125 inches
COB cost dollar per PAR watt: $0.84
Electric cost
@12/12 in 30 days: $70.96
Electric cost @18/6 in 30 days: $106.44
Cost per cob: $23.0
Heatsink cost per inch cut: $1.74
Total cobs cost: $460.0
Total heatsink passive cooling cost: $652.50
Total heatsink active cooling cost: $217.50