This is a rather funny argument to pop up in an LED thread, but it does bring up something people often over look. LED does produce so little heat compared to HID that you may have issues with low temps using LED.
I feel its accurate people say LED puts out about 80% less heat per watt than HPS. I have a 395w (it really uses that much, not half) that I use in a grow tent in my 12x12 bedroom (counting closet). I always keep my bedroom door and heat vent closed, and if its cold outside like it usually is around Kent/Seattle (low 60s to low 50s most of the year), I don't even need to open the window unless my computer is on (just the light only raises bedroom ambient 2 degrees after a whole day (and even then it would only be by an inch or 2). *********
But some growers have said they had issues with LED not keeping their grow areas warm enough during the winter, especially if they had at all relied on their grow set ups to warm other parts of the house.
*********- When I had my 400w HPS instead of my 395w LED the temps in the tent below the light were at least 10 above ambient (bedroom tent is in), and above the light about 20 over (with LED under isn't any warmer, and above is only 7 degrees). With the window open all the way all day my room would always be 75-80 with as much power going into HPS
I feel its accurate people say LED puts out about 80% less heat per watt than HPS. I have a 395w (it really uses that much, not half) that I use in a grow tent in my 12x12 bedroom (counting closet). I always keep my bedroom door and heat vent closed, and if its cold outside like it usually is around Kent/Seattle (low 60s to low 50s most of the year), I don't even need to open the window unless my computer is on (just the light only raises bedroom ambient 2 degrees after a whole day (and even then it would only be by an inch or 2). *********
But some growers have said they had issues with LED not keeping their grow areas warm enough during the winter, especially if they had at all relied on their grow set ups to warm other parts of the house.
*********- When I had my 400w HPS instead of my 395w LED the temps in the tent below the light were at least 10 above ambient (bedroom tent is in), and above the light about 20 over (with LED under isn't any warmer, and above is only 7 degrees). With the window open all the way all day my room would always be 75-80 with as much power going into HPS