MiniRVPark Texas, need input for 3-Phase System for Wash House, Grid Tied, 17kW req.

[TexasMiniRVPark]

Howdy Folks,
Project scope: Micro RV Park going in Texas. 10 - 12 spots.
Will be putting in a shower room and wash room. The shower and wash room will be going into 20' shipping containers. I will be doing all modifications my self.
Work will be away from my normal area, 10' storage trailer to store tools and materials.
The washing room will require three phase power primary loads are washing machine and dryer, commercial units, with following requirements: 15 / 400 / 50 / 3 / 4 wire + ground (kW/Volts/Hertz/Phase/Wire). I have built two solar systems for my self already so some experience, background in various trades, comfortable with electricity. Never designed a three phase system for this application.
Plan is to use server rack batteries for backup, large solar array, grid tied with necessary inverters, and a just in case generator for system backup.
The shower house will run electric hot water heaters which are split phase and not a big issue there.
Any input on this project would be appreciated. The concept is a Micro RV Park that produces some of its own food, and offers several business spots out of storage containers. Would like to be completely off the grid but tied for convenience.

 

[galstaf]

I just got a EG4 package deal with the 4 batteries, 28 panels, rack, inverters, etc. The seller (signature solar) modified the package contents with changes to the panels and some other things and kept the free shipping, etc; you just need to talk to one of their sales guys to help you put it together vs. buying online.

Their inverters are designed to do 3 phase (120 degree phase difference), but you will need 3 of them for that and it will get you to the 18kW output you are looking for.
A few folks here don't like Sig Solar, but they are probably the best value for money, and their is a lot of info on setting up their stuff on youtube so plenty of support.
Plus they are based in Tx, so may possibly be close to you. Or hours away. Texas is a big place.

If you run them 240 split phase the phases won't be perfectly opposed (180 degrees apart), but they will be fine for things like resistance loads.

 

[HighTechLab]

You can do a 400v 3 phase 50hz Y system with 3x 230v inverters (I recommend victron, they have exact 5kVa models that work for this).

Pair it with a Cerbo GX and some SOK 48v100ah server rack batteries and you are set.

You did mention Grid-tie though. Texas power grid is 60hz, right? I find this voltage/frequency combination strange.

I build 3 phase and other multi-inverter systems all day so this is very familiar to me.

 

[TexasMiniRVPark]

I just got a EG4 package deal with the 4 batteries, 28 panels, rack, inverters, etc. The seller (signature solar) modified the package contents with changes to the panels and some other things and kept the free shipping, etc; you just need to talk to one of their sales guys to help you put it together vs. buying online.

Their inverters are designed to do 3 phase (120 degree phase difference), but you will need 3 of them for that and it will get you to the 18kW output you are looking for.
A few folks here don't like Sig Solar, but they are probably the best value for money, and their is a lot of info on setting up their stuff on youtube so plenty of support.
Plus they are based in Tx, so may possibly be close to you. Or hours away. Texas is a big place.

If you run them 240 split phase the phases won't be perfectly opposed (180 degrees apart), but they will be fine for things like resistance loads.

So inductive loading is going to be a problem, such as the AC motors that power the agitation cycle, and drying spin feature correct?
So the EG4 inverters are not a good for inductive loads, recap? Thank you for the reply!

 

[TexasMiniRVPark]

You can do a 400v 3 phase 50hz Y system with 3x 230v inverters (I recommend victron, they have exact 5kVa models that work for this).

Pair it with a Cerbo GX and some SOK 48v100ah server rack batteries and you are set.

You did mention Grid-tie though. Texas power grid is 60hz, right? I find this voltage/frequency combination strange.

I build 3 phase and other multi-inverter systems all day so this is very familiar to me.

 

[galstaf]

So inductive loading is going to be a problem, such as the AC motors that power the agitation cycle, and drying spin feature correct?
So the EG4 inverters are not a good for inductive loads, recap? Thank you for the reply!

They should be fine for inductive loads as long as you plan for up to 10X startup surge. This means enough inverter and batteries to handle the surge.

I am actually doing something fairly similar to you with a small camper park. I priced the commercial coin style washers and dryers and they are not cheap... I wondered why you think you need that sort of capacity for a relatively small park.
I am just going with 3 or 4 pairs of residential style washer dryers with app controlled power timers. Customers pay by the hour to use the machine. Much less expensive to buy and easier to replace/maintain. Cheap enough to keep a pair on hand as a backup. Also easier to sell if the park doesn't work out. Plus no messing around with 400V 3ph power either!
Just a thought.

 

[TexasMiniRVPark]

They should be fine for inductive loads as long as you plan for up to 10X startup surge. This means enough inverter and batteries to handle the surge.

I am actually doing something fairly similar to you with a small camper park. I priced the commercial coin style washers and dryers and they are not cheap... I wondered why you think you need that sort of capacity for a relatively small park.
I am just going with 3 or 4 pairs of residential style washer dryers with app controlled power timers. Customers pay by the hour to use the machine. Much less expensive to buy and easier to replace/maintain. Cheap enough to keep a pair on hand as a backup. Also easier to sell if the park doesn't work out. Plus no messing around with 400V 3ph power either!
Just a thought.

That's an excellent thought. I hadn't considered some sort of application control system.
I'm the sort of person who always wants to over-build something so course I'm looking at a three phase system .
It would be cheaper to use residential washer with such a small park, and it would be easier to re-sell.
I was thinking to use "soft start" kits for the inductive loads in the system. Are you familiar with them? They allow for much less in terms of the LRA demand at startup, normally within 10% of target voltage/amperage LRA is 6X normal operating wattage to start. That's been my observation anyway. Can you recommend an application for the timing / payment acceptance?

 

[galstaf]

That's an excellent thought. I hadn't considered some sort of application control system.
I'm the sort of person who always wants to over-build something so course I'm looking at a three phase system .
It would be cheaper to use residential washer with such a small park, and it would be easier to re-sell.
I was thinking to use "soft start" kits for the inductive loads in the system. Are you familiar with them? They allow for much less in terms of the LRA demand at startup, normally within 10% of target voltage/amperage LRA is 6X normal operating wattage to start. That's been my observation anyway. Can you recommend an application for the timing / payment acceptance?

I haven't researched the paid appliance outlet thing yet, so not picked a vendor, but I am already using an app by Liftmaster for gate access control that can also allow access to a mail room. It supports access by Amazon drivers for if customers want something large shipped to the site. It also tells you who is coming and going and when.

For the washroom, if you have a number of smaller residential machines, the start up load will be probably something you don't have to think about. You can skip the whole 3 phase nonsense too ;-)

How are you powering the RV sites? I was thinking some sort of solar canopy that would provide shade from the summer sun as well as powering the RVs themselves.

 

[TexasMiniRVPark]

I haven't researched the paid appliance outlet thing yet, so not picked a vendor, but I am already using an app by Liftmaster for gate access control that can also allow access to a mail room. It supports access by Amazon drivers for if customers want something large shipped to the site. It also tells you who is coming and going and when.

For the washroom, if you have a number of smaller residential machines, the start up load will be probably something you don't have to think about. You can skip the whole 3 phase nonsense too ;-)

How are you powering the RV sites? I was thinking some sort of solar canopy that would provide shade from the summer sun as well as powering the RVs themselves.

My dream is to build out the units to mirror how I live, completely off grid, which means proper design. Most of the RV's I've seen are not designed that way so power hogs, system being cost prohibitive, at least for my budget.

So then for now the only off grid, power wise, is going to be the wash room, and bathroom. The RV spots will be typical 30-50 Amp utility powered sites.

This is going to be the business credit building site that I can then seek investor capital or boot strap the real project. Which is the tiny houses that are completely off grid, water, power and sewer.

That's how I currently live and have realized the huge benefits financially. It's hard for people who don't live this way to realize how amazing it really can be to be debt free, even if you have to live smaller than you're used to!

Thanks for the app suggestion. I guess there has to be a solution that someone has already built.