Btu

[memyselfandI]

I am trying to find out how many BTU's a 400W HPS High bat light fixture has. Any clues?

 

[memyselfandI]

I found it. It is 3.41 BTU per watt

 

[ty]

For an acurate measurement, I think you need to know the actual useage of that fixture instead of just using it's lamp wattage.