So are you aiming to cover a 4'X8' or 32 ft²? If so,
Since heat is an issue, the efficiency (and efficacy) may affect your grow more than the direct electrical savings of the lamp. To compare heat in your 4'X8':
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2X 1000W HPS DE bare, 40.8% efficient =
960 PPFD
1184W of heat
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4xVero29 x 10 bars
10 x HLG-185H-C1400B x 43.90 euro = 439 + 45.07 shipping
40 x Vero29 x 24.79 euro = 991.60 + 112.67 shipping
1588.34
4xVero29 x 50.96
[email protected]@43.03% = 21.93 PARW x 4 = 87.71 PARW/bar
1230 PPFD
1163W of heat
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4xCXB3070 AD x 10 bars
10 x HLG-185H-C1400B x 43.90 euro = 439 + 45.07 shipping
40 x CXB3070 AD x 32.87 euro = 1314.80 + 112.67 shipping
1977.87
4xCXB3070 AD x 49.83
[email protected]@48.02% = 23.92 PARW x 4 = 95.71 PARW/bar
1346 PPFD
1040W of heat
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4xCXB3590 CD x 10 bars
10 x HLG-185H-C1400B x 43.90 euro = 439 + 45.07 shipping
40 x CXB3590 CD x 41.87 euro = 1674.80 + 112.67 shipping
2271.54
4xCXB3590 CD x 49
[email protected]@56.2% = 27.54 PARW x 4 = 110.15 PARW/bar
1712 PPFD
876W of heat
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In this example all the COB setups are very high intensity, maybe too high for a 4'X8'. So if you cut the number of CXB3590s in half to 980W, you get:
856PPFD
438W of heat
So that is equal intensity/efficacy as the 2000W of HPS but
one third the heat.