First big build size ad\vice needed .

[CabinBill]

Hello,
I am looking to build a solar powered system to run my off grid home in central NH .
My home has a 100 amp panel which is powered by a 5500 watt generator .
The panel has breakers which operate a ceiling fan, microwave, submersed well and some 110 plugs and lights .
My future improvements include : a freezer, washer and dryer .
I currently have a 400w inverter, 50w solar panel and a 12v car battery to operate some lights and a tv .
I am wondering which Growatt (all in one) I should purchase, how many panels and how many lithium batteries .
I am willing to spend the money but can't afford to make a costly mistake .
I am also legally blind and have a hard time doing research .
So, I would appreciate any advice!
Thanks in advance for reading !

 

[RobertGreen]

Welcome to the forum!
I see that you don't mention any provision for heating; I assume that you're not using electricity to provide your heat?
Will you be needing 240v power for your well pump or the planned dryer? In other words, is your well pump/generator 120v?

Usually the first thing that is recommended when you're trying to make a design for your system is to assess your actual needs with an energy audit:

System Energy Audit and Sizing Spread Sheet

To get the spreadsheet, click on the orange Button in the upper right of this page. This sheet is intended to help you plan your system. Fill it out down to the last decimal place, look at the results..... and then make your best guess;)...

diysolarforum.com

 

[CabinBill]

Welcome to the forum!
I see that you don't mention any provision for heating; I assume that you're not using electricity to provide your heat?
Will you be needing 240v power for your well pump or the planned dryer? In other words, is your well pump/generator 120v?

Usually the first thing that is recommended when you're trying to make a design for your system is to assess your actual needs with an energy audit:

System Energy Audit and Sizing Spread Sheet

To get the spreadsheet, click on the orange Button in the upper right of this page. This sheet is intended to help you plan your system. Fill it out down to the last decimal place, look at the results..... and then make your best guess;)...

diysolarforum.com

Thank You Robert !
I may go with an LP dryer if the system cannot handle an electric one . Being this far from the equator in central NH . We don't get full sun daily . I'm not sure if I will be able to produce enough . I would rather go electric . My pump is on a 20 amp double breaker . My gen. is connected to the house with a four prong 30 amp wire . I currently heat with firewood and have been doing that for 28 years, though I would love to put in a small lp furnace in the future . I will check out the link you sent . Thanks again !!! I really appreciate your input ! I cannot check this as often as most people due to very poor vision (FYI) .

 

[MichaelK]

Thank You Robert !
I may go with an LP dryer if the system cannot handle an electric one . Being this far from the equator in central NH . We don't get full sun daily . I'm not sure if I will be able to produce enough . I would rather go electric . My pump is on a 20 amp double breaker . My gen. is connected to the house with a four prong 30 amp wire . I currently heat with firewood and have been doing that for 28 years, though I would love to put in a small lp furnace in the future . I will check out the link you sent . Thanks again !!! I really appreciate your input ! I cannot check this as often as most people due to very poor vision (FYI) .

You really need to start out with realistic expectations.

Let's start with the well-pump. This statement "pump is on a 20 amp double breaker" suggests it's a 240VAC pump and it's a big one, if it needs a 20A breaker. I've got a 10A breaker on my 1hp pump. So, I'd guestimate you have at least a 2hp pump.

These are the kinds of things you shouldn't guess at. Get a clamp meter that can read "inrush current" and determine what the pump's draw is. That's what I did and I correctly sized my inverter to handle the pump's startup draw (9200W). I used a Uni-T 216C to measure inrush.

Likewise, an electric dryer is most likely going to be 240VAC, and it's electrical draw is probably as large or larger then your well-pump.

So, we are talking a BIG system. Keep in mind that most AiO inverter have no surge capacity, so either you'll need multiple AiOs in parallel, or a big low-frequency based inverter like a Radian or XWpro.

I'd suggest that you could be happy with about 3-5kWh of power per day, excluding the pump and electric dryer. This is very doable with 24V and ~1500W of panels. You'll be able to run your refrigerator, freezer, and a propane drier just fine on that. Throw in either the pump or the dryer, and you need to scale up to a BIG 48V system immediately.

 

[Hedges]

Can your generator start and run the pump?
Have a large above-ground or in-ground water tank. Use 12V Surflow pump to send water to house.
When you need to refill water, run the generator.

Is generator air cooled? (most likely) The air may have some odors so not good for drying. Route the exhaust through a car radiator (and muffler after that.) Put the radiator on back of a clothes dryer. Run the dryer on 115V (draws 1/4 the power of 230V), or air fluff. Let exhaust heat exchanger serve to make hot air for dryer. "Combined Heat and Power".

If you have enough solar, there are condensing dryers, and there are heat-pump dryers.

 

[RobertGreen]

If it were me, I would rather switch to one of the grundfos submersible pumps with soft start rather than drastically scaling up the size of the entire system (assuming that a suitable pump is available and that the pump is the biggest load that is dictating the size of the system)
A lot of these pumps have a maximum draw between 1000-2000w for a pump that in a conventional configuration would have been several times higher.
I've often enough seen these pumps go for a few hundred dollars on ebay. There's more information on this in the "Solar Water Pumps" section of the forums.

 

[CabinBill]

Thank You Robert !
I may go with an LP dryer if the system cannot handle an electric one . Being this far from the equator in central NH . We don't get full sun daily . I'm not sure if I will be able to produce enough . I would rather go electric . My pump is on a 20 amp double breaker . My gen. is connected to the house with a four prong 30 amp wire . I currently heat with firewood and have been doing that for 28 years, though I would love to put in a small lp furnace in the future . I will check out the link you sent . Thanks again !!! I really appreciate your input ! I cannot check this as often as most people due to very poor vision (FYI) .

You really need to start out with realistic expectations.

Let's start with the well-pump. This statement "pump is on a 20 amp double breaker" suggests it's a 240VAC pump and it's a big one, if it needs a 20A breaker. I've got a 10A breaker on my 1hp pump. So, I'd guestimate you have at least a 2hp pump.

These are the kinds of things you shouldn't guess at. Get a clamp meter that can read "inrush current" and determine what the pump's draw is. That's what I did and I correctly sized my inverter to handle the pump's startup draw (9200W). I used a Uni-T 216C to measure inrush.

Likewise, an electric dryer is most likely going to be 240VAC, and it's electrical draw is probably as large or larger then your well-pump.

So, we are talking a BIG system. Keep in mind that most AiO inverter have no surge capacity, so either you'll need multiple AiOs in parallel, or a big low-frequency based inverter like a Radian or XWpro.

I'd suggest that you could be happy with about 3-5kWh of power per day, excluding the pump and electric dryer. This is very doable with 24V and ~1500W of panels. You'll be able to run your refrigerator, freezer, and a propane drier just fine on that. Throw in either the pump or the dryer, and you need to scale up to a BIG 48V system immediately.

I just bought the meter and will measure the inrush . I have to depend on pictures of my panel, which I have to expand to see . I am legally blind and have been doing all trades (electrical, plumbing, mechanics, furniture builds and general construction ) my whole life . All the research I have been doing on solar is pushing my physical limits . This system is going to power a 980sq ft cabin . Which we will be moving into in the spring . Thanks again

 

[CabinBill]

If it were me, I would rather switch to one of the grundfos submersible pumps with soft start rather than drastically scaling up the size of the entire system (assuming that a suitable pump is available and that the pump is the biggest load that is dictating the size of the system)
A lot of these pumps have a maximum draw between 1000-2000w for a pump that in a conventional configuration would have been several times higher.
I've often enough seen these pumps go for a few hundred dollars on ebay. There's more information on this in the "Solar Water Pumps" section of the forums.

I will look into the pump . Thanks again

 

[CabinBill]

Can your generator start and run the pump?
Have a large above-ground or in-ground water tank. Use 12V Surflow pump to send water to house.
When you need to refill water, run the generator.

Is generator air cooled? (most likely) The air may have some odors so not good for drying. Route the exhaust through a car radiator (and muffler after that.) Put the radiator on back of a clothes dryer. Run the dryer on 115V (draws 1/4 the power of 230V), or air fluff. Let exhaust heat exchanger serve to make hot air for dryer. "Combined Heat and Power".

If you have enough solar, there are condensing dryers, and there are heat-pump dryers.

My gen. does run the pump and is air cooled . The radiator idea is interesting and somthing to consider down the road . I do have 275, 100 and 65 gallon tanks . The 65 is indoors . The others I have to drain in the winter . Great ideas Thanks

 

[MichaelK]

I just bought the meter and will measure the inrush . I have to depend on pictures of my panel, which I have to expand to see . I am legally blind and have been doing all trades (electrical, plumbing, mechanics, furniture builds and general construction ) my whole life . All the research I have been doing on solar is pushing my physical limits . This system is going to power a 980sq ft cabin . Which we will be moving into in the spring . Thanks again

Here's an option I can point out to you. I'm guessing that your pump is going to have a big inrush. We'll have to wait till you get numbers to talk more. For my 1hp pump, that has a 38A inrush, I chose the XW+6848 to power it. It works!

I can understand that you might not want to dive in that deep on your starter system, so here is an option that might allow for future expansion. Schneider makes a smaller split-phase Conext series, both at 24V and 48V. I have the Conext 4024 myself for my workshop. I like it, and it starts all my powertools flawlessly, though I'm not sure it would start my pump.

One capability though of the 4024 (or 4048) is that they can be paralleled for additional load handling. So, instead of a 7000W surge-wattage, the paralleled units can put out a 14,000W surge. This might be part of a future expansion plan for your cabin. You could install a single Conext now, just to get the lights on and the refrigerator cold, but then upgrade to a second unit once you want to power your pump.

 

[CabinBill]

Here's an option I can point out to you. I'm guessing that your pump is going to have a big inrush. We'll have to wait till you get numbers to talk more. For my 1hp pump, that has a 38A inrush, I chose the XW+6848 to power it. It works!

I can understand that you might not want to dive in that deep on your starter system, so here is an option that might allow for future expansion. Schneider makes a smaller split-phase Conext series, both at 24V and 48V. I have the Conext 4024 myself for my workshop. I like it, and it starts all my powertools flawlessly, though I'm not sure it would start my pump.

One capability though of the 4024 (or 4048) is that they can be paralleled for additional load handling. So, instead of a 7000W surge-wattage, the paralleled units can put out a 14,000W surge. This might be part of a future expansion plan for your cabin. You could install a single Conext now, just to get the lights on and the refrigerator cold, but then upgrade to a second unit once you want to power your pump.

Thanks, I'm learning !

 

[Rocketman]

Look at signature solar, they have some very interesting batteries in a rack mount and also sell an AIO(all in one) unit. Call and see what they recommend.

Good luck!