Load calculation for a Greenhouse

[electric wrangler]

Hello, my client is building a greenhouse in his backyard, aside from typical grow lights and some receptacles he has the following:

13kw tankless water heater (60 amp breaker)
9kw sauna (40 amp breaker)
9000 btu 120 volt minisplit (15 amp single pole breaker)

I haven't had to do any load calculations in the past, I am leaning towards either a 100 amp or 125 amp subpanel, but am curious what others would do.
Thanks for the help!
-Mark

 

[ptonsparky]

31 Kw @240 = 129
Dang close to a 125 and we don't know any other details. Most of it will not be on at the same time.

No, I didn't do any other calculations.
100 to a 125 isn't that big of a jump.

 

[ptonsparky]

You might be stretching a 200 amp SE if that is what have.

 

[augie47]

125 would be the least I would do and you might want to look at your service size if that's fed of your house panel.

 

[electric wrangler]

thanks guys, house panel is 200

 

[suemarkp]

31 Kw @240 = 129
Dang close to a 125 and we don't know any other details. Most of it will not be on at the same time.

No, I didn't do any other calculations.
100 to a 125 isn't that big of a jump.

Where did 31KW come from? He said 9000 BTU mini split, not 9000W. But there are other loads based on either square footage or the installed lighting. But the answer is probably still a 125A feeder.

 

[petersonra]

Hello, my client is building a greenhouse in his backyard, aside from typical grow lights and some receptacles he has the following:

13kw tankless water heater (60 amp breaker)
9kw sauna (40 amp breaker)
9000 btu 120 volt minisplit (15 amp single pole breaker)

I haven't had to do any load calculations in the past, I am leaning towards either a 100 amp or 125 amp subpanel, but am curious what others would do.
Thanks for the help!
-Mark

You are closing in on 100 amps just with the sauna and water heater. I would be looking at running a 150 amp feeder. Probably can get by with 125 amp but you never know what might get plugged in down the road.

 

[ptonsparky]

Where did 31KW come from? He said 9000 BTU mini split, not 9000W. But there are other loads based on either square footage or the installed lighting. But the answer is probably still a 125A feeder.

Guilty, I skipped the BTU part. Several times .

 

[electric wrangler]

Thanks for the help, I am going to try and talk him into buying a smaller sauna and or water heater...
It's only a 288 square foot space

 

[Jraef]

I'm sorry, but a SAUNA in a GREENHOUSE in the back yard, with AIR CONDITIONING and a WATER HEATER?
I'm intrigued...

 

[ptonsparky]

I'm sorry, but a SAUNA in a GREENHOUSE in the back yard, with AIR CONDITIONING and a WATER HEATER?
I'm intrigued...

Maybe they only have a couple plants. For personal use only, while in the Sauna.

 

[electric wrangler]

Yeah, it's unusual. Sounds like we'll upgrade the service to 400 amps and run 200 to the greenhouse, I know he'll need the extra power for future projects.