Most grow lights specify their radiant wattage in incandescent equivalents. The 2000W LED grow lights I'm familiar with actually consume only 200-300W out of the outlet. A standard residential circuit is limited by fuse/breaker to 15-20amps, which translates to a few thousand watts.

I thought of that but everywhere I look at specs it says 2000 watts. I do think you are right.

2000 watts seems pretty darn bright so Dan is most likely correct on the conversion aspect. Back when I used simple florescent tubes (4) to start indoor seedlings I think (if memory serves) that it totaled to about 40w per tube = 160 watts. It did the job for 2 flats/trays.

The formula is P=IE or Power equals current in amps times voltage. 20 amps with a 120 volt circuit would be 2400 watts. 15 amps on the same circuit would be 1800 watts. I'm thinking the 2000 watt grow light is a salesman's pitch, using the equivalent it would take to create that same amount of light with an incandescent bulb.

Kinda like using megabits instead of megabytes.

It is kinda dumb, quoting power in incandescent-equivalent, especially when they don't even take the trouble to tell you what the real power consumption is. Just quoting lumens is what we all should be doing. But the sales pitches for almost all bulbs is incandescent-equivalent these days. We routinely buy 100W LED light bulbs that actually draw 12W of real power.

Regardless of what the stated light output is, there should be a plate or tag located somewhere on the fixture (or on the power cord) that states the input voltage & amps of current used. If the bulb is removable, the wattage could also be listed on the bulb, in which case the power formula above would give the amperage.

I suspect that like others have already stated, the quoted wattage is the incandescent equivalent, and the actual current draw of the LEDs will be much less. When this question has come up in the past, the true power consumption was often located on the manufacturer's website... so absent a power tag, that might be worth a look.

I checked and no tag like in the pic, these are cheap lights (work good) so not to surprising. Yes I agree it is probably about 1/10 what it says. Silly to not tell you, even specs say it draws 2,000 watts! No way, if I had all that hooked up power strip would get hot, outlet, breaker trip etc. There are other things on that breaker I did not even list!

No way I had 5,200 watts in led lights, 100 wat elec heater, fan, heating matt, lights and misc other items all running on 1 circuit at the same time for days and it did not trip.

Just to be safe I plugged one 2000 watt light into a different outlet (probably still on the same breaker).

Turns out that "energy labels" are an EU requirement. We're not that good.