Off-Grid Solar System Builder

48V off-grid system from about $5,400

A complete 48V off-grid system for a house, cabin or homestead, built around an all-in-one inverter. The inverter, solar charge controller and battery charger come in one box.

Pick an inverter size, a 48V battery, a mounting method and your solar panels, then follow the build steps. The four builds below run from $5,437 for 5kW to $12,089 for 12kW.

Jump to: How it connects · Cost · Inverter · Battery · Mounting · Panels · Panels per string · Materials · Build it · Settings · Troubleshooting

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How the System Connects

Every build on this page has the same parts: solar panels, a PV disconnect, an all-in-one inverter, a 48V battery with a fuse or breaker, and a load panel. A generator can connect to the inverter’s AC input to charge the battery through long cloudy stretches.

The steps below follow that order. Steps 01 to 04 pick the parts. Step 05 lists the materials. The build cards show how to mount, wire and start it.

What It Costs

Inverter, battery and solar panels for each size. Each build uses the battery and panel count from the sizing sections below.

Part	Small 5kW	Medium 6kW	Large 10kW	Extra Large 12kW
Inverter	SGPWOSAY 5000W $768	EG4 6000XP $1,450	SUNGOLDPOWER 10kW $1,422	EG4 12000XP $2,100
Battery	Yixiang 16kWh $2,249	Yixiang 16kWh $2,249	Yixiang 32kWh $3,699	Yixiang 32kWh $3,699
Solar panels	8 × SunGold 590W 4,720W, $2,420	14 × SunGold 590W 8,260W, $4,370	16 × SunGold 590W 9,440W, $4,770	31-panel pallet (28 used) 16,520W, $6,290
Total	$5,437	$8,069	$9,891	$12,089

Prices checked November 13, 2026. They change, so use the buttons below for the current price. Panel prices use ShopSolar’s 4, 6, 8 and 10 packs. Racking, wire, fuses, breakers, the load panel and tools are extra. To pass inspection, swap in a UL listed battery from Step 02: the RUiXU Lithi 16 ($3,099) in place of the 16kWh adds $850, and the ECO-WORTHY Cubix 4-pack ($3,480) in place of the 32kWh costs $219 less but holds 20.48kWh instead of 32kWh.

Choose An  "All-In-One Inverter"

If you are powering a house, cabin or homestead with off-grid solar, a 48V off-grid all-in-one inverter is the simplest way to do it.

Below are the four I recommend, from 5kW to 12kW. I have tested all four.

Each unit has everything you need to go off-grid:

Small

SGPWOSAY 5000W Inverter

120V only. Fits cabins and small homes with no 240V loads.

Medium

EG4 6000XP Inverter

Runs 120V and 240V loads in cabins and small homes.

Large

SUNGOLDPOWER 10000W Inverter

10kW for larger homes, at a lower price than the 6000XP.

Extra Large

EG4 12000XP Inverter

Built to run a house. Two in parallel give 24,000W.

The Four Inverters Side by Side

All four run from a 48V battery and include the inverter, solar charge controller and battery charger. The SGPWOSAY puts out 120V only, so it cannot run 240V loads like a well pump or dryer unless you parallel two or more.

	SGPWOSAY 5000W LOWEST PRICE	EG4 6000XP	SUNGOLDPOWER 10kW	EG4 12000XP
Price	$768	$1,450	$1,422	$2,100
Output	5,000W	6,000W	10,000W	12,000W
AC output	120V	120/240V	120/240V	120/240V
Solar input	5,500W	8,000W	11,000W	24,000W
Solar inputs (MPPT)	1	2	2	2
MPPT range	120 to 450V	120 to 385V	125 to 425V	120 to 385V
Max PV voltage	500V	480V	500V	480V
Battery charging	100A (40A from AC)	125A solar, 115A AC	200A	250A
Generator input	Shares the AC input	Separate GEN terminals	Shares the AC input	Separate GEN terminals
Rated for	Indoors	Indoors	Indoors	Indoors

Specs from each manual and data sheet. Prices checked November 13, 2026.

The inverters shown above MUST be mounted indoors. They cannot be mounted outside.

If you want a system you can mount outside, see my EG4 Hybrid System Builder. Hybrid inverters run off-grid too. They cost more up front, and the inverter and batteries there are outdoor rated.

Choose a 48V Battery

Pick the battery that matches your inverter size. The top two are budget batteries with no UL listing. The bottom two carry UL listings for systems that need to pass inspection. Every button goes straight to the product.

Yixiang 16kWh

Budget pick for the 5kW and 6kW builds. 16kWh, 51.2V, EVE 314Ah cells and a JK BMS. Arrives as a kit you assemble. No UL listing, so it cannot go in an inspected system. About $2,249.

Yixiang 32kWh

Budget pick for the 10kW and 12kW builds. 32kWh, 51.2V, 628Ah with a JK 300A BMS. About 600 lb, so build it where it will stay. No UL listing. About $3,699.

RUiXU Lithi 16

Code-compliant pick for the 5kW and 6kW builds. 16kWh, 51.2V, 314Ah. The seller lists UL 1973 and UL 9540. IP55 case with self-heating and wheels. About $3,099.

ECO-WORTHY Cubix 100, 4-Pack

Code-compliant pick for the 10kW and 12kW builds. Four 5.12kWh batteries, 20.48kWh total, UL 9540 and UL 1973 listed. Each handles 100A, 400A for the four. Parallel and communication cables included. 10-year warranty. About $3,480.

How Much Battery You Need

At full output the inverter pulls its watts ÷ 48V from the battery. A 10,000W load pulls 10,000 ÷ 48 = about 210A. Pick a battery that can deliver that.

Inverter	Battery current at full output	Budget battery	Code-compliant battery
SGPWOSAY 5000W	About 105A	One Yixiang 16kWh	RUiXU Lithi 16
EG4 6000XP	140A max (manual)	One Yixiang 16kWh	RUiXU Lithi 16
SUNGOLDPOWER 10kW	About 210A	Yixiang 32kWh, or two 16kWh in parallel	ECO-WORTHY Cubix 100, 4-pack
EG4 12000XP	250A max (manual)	Yixiang 32kWh, or two 16kWh in parallel	ECO-WORTHY Cubix 100, 4-pack

The EG4 12000XP manual calls for at least 400Ah of battery. One Yixiang 16kWh is 314Ah, so it takes the 628Ah 32kWh pack or two 16kWh packs. The 32kWh pack costs less ($3,699) than two 16kWh packs ($4,498) and has a JK 300A BMS.

How long it lasts

Runtime = battery Wh ÷ load W. A 16kWh battery holds 16,000Wh, so at a steady 1,000W it lasts 16 hours. Solar during the day adds hours.

Two or more batteries

Wire them in parallel through bus bars: every + to the + bus bar, every − to the − bus bar, with cables of the same length. One fuse or DC breaker goes on the positive cable to the inverter. Sizes are in Step 05.

Choose a Solar Panel Mounting Method

Currently the most popular method for mounting panels is to use a ground mount. This is why:

The only downside is you need room to mount them. If you have zero space available, I strongly suggest hiring a professional to assess your houses roof and have them mount your array. That way they can pick the right equipment for the job and pull the required permits.

Ground Mount

Fast to assemble, engineered and legal for permitted installs.

See my picks →

Roof Mounted

Low-profile systems engineered for secure, long-lasting roof installations.

See my picks →

Solar Carports

Dual-purpose structures that provide shade while generating clean energy.

See my picks →

Choose Your Solar Panels

Most solar panels today have incredible quality and output. They can last decades with zero issues.

But keep a few things in mind:

Buy a few extra, just in case.
The more you buy, the cheaper they get.
They are heavy and large. Ask for help. Do not install on windy days alone.
Do not connect them until it is dark. The solar panel creates a very dangerous voltage. Best to wait till night time.

Glass is glass, and glass breaks. When you put multiple glass panels on a pallet, it is common for some to break. Buy from a reputable company so you can get refunded for these panels.
400W to 440W panels are the easiest for one person to handle. For the lowest price per watt, buy a pallet: the cost table uses SunGold 590W bifacial panels at about $0.34 per watt for a 31-panel pallet.
Wire panels in series into strings. The section below shows how many panels go in each string for each inverter.

Used Solar Panels

Lowest price. But is it worth it? Used panels have great output, but the warranty is pretty limited. Be sure to buy spares.

Current Connected

Fantastic deals on new panels. If something goes wrong with shipping, you’re good to go.

Signature Solar

The best method to get a good price on new panels is to get a package deal with Signature Solar.

How Many Panels Per String

Panels wired in series make a string, and their voltages add up. The string has to sit inside the inverter’s MPPT range to charge, and stay under its max PV voltage on the coldest morning. Go over the max and you can destroy the inverter.

Size a string for any panel

Find Voc and Vmp on the label on the back of the panel.
Multiply Voc by the number of panels in the string.
Add about 15% for a −22°F (−30°C) morning. That figure comes from a −0.28%/°C temperature coefficient; use the one on your panel’s data sheet. Keep the result under the inverter’s max PV voltage.
Multiply Vmp by the number of panels. Keep it inside the MPPT range.

Example: 7 SunGold 590W panels on an EG4 6000XP. 7 × 52.35V = 366V, and about 423V on a −22°F morning, under the 480V max. 7 × 44.4V = 311V Vmp, inside the 120 to 385V range.

Current matters too. One string per input fits all four inverters. Two strings in parallel on one input fit only the EG4 12000XP, which takes 35A per input. The 6000XP takes 17A per input, and the SUNGOLDPOWER units take 22A.

Inverter	Panels per string	Strings	Array
SGPWOSAY 5000W	8	1	4,720W (5,500W max)
EG4 6000XP	7	2	8,260W (8,000W used)
SUNGOLDPOWER 10kW	8	2	9,440W (11,000W max)
EG4 12000XP	7	4, two per input	16,520W (24,000W max)

Obtain Materials  and Supplies

The kits do not include everything. Here is what people miss on the first trip to the hardware store. The wire and fuse sizes for each inverter are in the table below.

THHN Wire

THHN wire runs from the inverter to the load panel, inside conduit. The bigger the inverter, the bigger the wire. See the table below.

Tools

Wire strippers, a cable cutter, a crimper for the battery lugs and a torque wrench.

Flex Conduit

Beginner friendly method to connect the inverter to a breaker box. Easy to purchase at any hardware store.

Romex

Romex is the common name for the cable that runs from a load panel to an outlet. 12 AWG Romex on a 20A breaker covers most home outlet circuits.

Circuit Breakers and Load Panel

Do not let the load panel scare you. Hardware stores sell panels and breakers, and they are simple to wire. If you are not comfortable doing it, hire an electrician.

Battery Cable, Fuses and AC Wire

Battery cable, fuse and AC wire sizes from each inverter’s manual. Your electrician sizes the AC breakers and wire for your panel and run length.

Inverter	Battery cable	Battery fuse or DC breaker	AC wire	PV wire
SGPWOSAY 5000W	2 AWG	200A	8 AWG in and out, 63A breaker	10 AWG
EG4 6000XP	2/0 AWG	200A	8 AWG grid, gen and load	10 AWG
SUNGOLDPOWER 10kW	4/0 AWG	250A	6 AWG in and out, 63A breaker	10 AWG
EG4 12000XP	4/0 AWG, or two 2/0 AWG pairs	300A	3 AWG grid and load, 4 AWG generator	10 AWG

The 6000XP manual lists 1 AWG battery cable and no fuse size. 2/0 AWG copper is rated 175A at 75°C (NEC Table 310.16), and NEC 240.4(B) allows the next standard fuse size up, 200A. That covers the inverter’s 140A max discharge and uses the same parts as the 5kW build. The SGPWOSAY manual allows 12 AWG PV wire; 10 AWG is the same price and runs cooler.

What to buy

Class T fuse (the linked one is 200A, right for the 5kW and 6kW builds) or DC MCCB breaker (pick 200A or 300A on the listing). It goes on the positive battery cable. For the 250A SUNGOLDPOWER 10kW, buy a 250A Class T fuse.
Bus bars if you have more than one battery.
2/0 AWG battery cable kit for the 6000XP or a pair of 2/0 cables on the 12000XP. The other sizes are on my wire and connectors page.
PV disconnect switch, one per string. Pick the DC1000V 30 Amp option: the 400V options are rated below these strings.
10 AWG MC4 extension cable from the array to the disconnect.
Clamp meter to check polarity and voltage before startup.
Inch-pound torque wrench for the battery lugs.
Crimpers, cutters and strippers: see my crimpers and tools page.

Shopping Checklist

Order online

1 inverter (Step 01)
Battery: one 16kWh for 5kW to 6kW, a 32kWh or two 16kWh for 10kW to 12kW (Step 02)
Solar panels (Step 04) and racking (Step 03)
Battery cable and lugs, sized from the table above
Class T fuse or DC breaker, sized from the table above
Bus bars if you have more than one battery
One PV disconnect per string rated 500V DC or more, and 10 AWG PV wire with MC4 connectors
Any tools you do not own

Hardware store

THHN wire and flex conduit from AC OUT to the load panel
Load panel with a main breaker, and branch breakers
12 AWG Romex for 20A outlet circuits
Ground wire, and a ground rod if your electrician calls for one
Lag screws or anchors for the inverter bracket

Download the build sheet (PDF): specs, wire sizes, string sizing, startup order and bond settings for all four inverters on two pages.

Build Your System

If you do not understand a step, stop and ask on the DIY Solar Forum or hire a professional. Every size on this page builds the same way. Keep every breaker and switch off until card 05.

01 / Mount Your Main Components

Mount the Batteries

They are the heaviest part of the system. Make sure they are switched off before you move or work on them. Set them on the floor close to the inverter so the battery cables stay short.

Mount the Inverter

The inverter comes with a mounting plate. Screw it into the wall studs, then lift the inverter onto it with a helper. The EG4 6000XP weighs 53 lb and the 12000XP weighs 105 lb. Leave the clearance shown in your manual.

Mount a Load Panel Next to the Inverter

Mount a load panel on the wall next to the inverter. Every circuit the system powers runs from this panel.

02 / Mount Your Solar Panels

Angle the panels toward the equator. In the northern hemisphere, face them south.
Level the ground, or make sure the concrete slab is flat.
Build your rack. To watch me build one, click here.
Secure it with ballast, concrete anchors or earth spikes.
Mount the panels on the rack, but do not connect them to anything.
Run wire to the array. Use direct burial rated wire or conduit.

03 / Wire Up Your System

Once everything is mounted, connect it together with every breaker and switch off.

Connect the batteries in parallel.

Run each battery’s + and − to a pair of bus bars, all with cables of the same length. Then run one red cable from the + bus bar to BAT+ on the all-in-one, through the fuse or DC breaker, and one black cable from the − bus bar to BAT−. Torque every lug to the value in the manual.

Connect the all-in-one to the load center or breaker box.

Run THHN wire in conduit from AC OUT to the load panel’s main breaker. The wire size for each inverter is in the table in Step 05.

Connect the solar array wires to the all-in-one.

Run the PV wire from the array to the PV disconnect, then to the PV input. Do not plug in the panels yet, and leave the PV disconnect off.

04 / Connect the Solar Panels to Your System

A string of panels in sunlight puts out hundreds of volts DC. Follow these steps in order.

Wait until nighttime and connect the solar panels in series.

You can cover the panels with a blanket during the day, but for a first system, do it at night. Plug the panels together in series: the + of one panel to the − of the next. MC4 connectors only plug + into −.

Connect your solar array to the wires that run back to your system.

Keep the PV disconnect off while you make this connection.

Final step is to check the polarity at the PV input on the all-in-one.

Before you turn anything on, check polarity. With the PV disconnect off, put the meter’s red probe on the + wire from the array and the black probe on the − wire. Even at night the array reads a few volts. A positive reading means the polarity is right. A negative reading means the wires are swapped somewhere between the array and the inverter. Check that the reading is under the inverter’s max PV voltage too.

05 / Turn Your System On.

Everything off. Check battery and PV polarity and voltage with a meter.
Turn on the battery breaker on the inverter.
Turn on the batteries, one at a time.
Turn on the inverter’s power switch and check the screen for warnings.
Turn on the PV disconnect.
If a generator or the grid feeds AC IN, turn that breaker on.
Turn on the output breaker (on EG4 units, also the EPS Output switch), then the load panel’s main breaker. Turn loads on one at a time, smallest first.

Then connect the WiFi dongle, update the firmware and check the settings below. Each manual lists its own order; follow it where it differs. To shut down, reverse the order.

That's it

You now have a working solar power system. Check the charging on a sunny day: if 4,000W of panels charge at only 300W in full sun, something is wrong. If you need help with setup, post your problem on the beginner forum.

Settings to Check After Startup

Check these on the inverter screen or app before you put a full load on it. Menu names differ by brand, so match them up in your manual.

Setting	Set it to
Battery type	Lithium (LiFePO4). If the battery talks to the inverter over CAN or RS485, pick the BMS or closed-loop option and the protocol your battery maker lists.
Charge voltage	Your battery maker’s number for a 16-cell LiFePO4 pack. The Yixiang JK BMS settings on my budget backup page charge at 3.45V per cell, 55.2V.
Low-voltage cutoff	Your battery maker’s number. The EG4 12000XP default is 42.0V.
Max charge current	No higher than your battery’s BMS rating.
Output priority	Solar first, then battery. The grid or generator only as backup.
Neutral-ground bond	Enabled for a system with nothing else connected. See Helpful Tips below.
AC input	Generator mode if a generator feeds AC IN.

How to Safely Connect the Grid

The steps above are for an off-grid system with no other power source. If you connect the inverter’s AC input to the grid, or its output to your house wiring, change the neutral-ground bond setting first.

Neutral-Ground Bond Setting

On the EG4 6000XP this is setting 26 (shown above). The inverter must be in standby to change it: turn the EPS Output switch off.

Range: Enable or Disable

Default: Enable

One Neutral-Ground Bond per System

A neutral-ground bond connects neutral to earth ground. A system can have only one. With two, neutral current flows on the ground wires.

Off-grid with nothing else connected: enable the inverter’s bond. If your inverter has no setting, install the green bonding screw in the load panel instead. Not both.
Feeding a house that has its own bond at the main panel: disable the inverter’s bond.

Inverter	Setting	Default
SGPWOSAY 5000W	Menu 63, N-G automatically connect	Disabled
EG4 6000XP	Setting 26	Enabled
SUNGOLDPOWER 10kW	Menu 63, Auto N-PE connection	Disabled
EG4 12000XP	N-PE Connect (Inner), Application tab	Check the screen

On a mobile system that plugs into an AC source, like a hand cart solar system, you have to change this setting every time you plug in.

If your system keeps its own bond but needs grid charging for a few days in winter, use a separate AC battery charger. Plug it in and the inverter’s bond stays as it is. A WiFi outlet or timer can run the charger at set times.

Can I Back Up My Whole House With This System, Legally?

Yes, with a licensed electrician. The electrician installs a transfer switch for your critical loads and feeds it from the off-grid load panel through a two-pole breaker. They size the wire, ground the system to the NEC, and decide whether your site needs a ground rod or surge protection. Do not earth ground the system yourself if you are not qualified.

The details depend on where the system sits, whether you have more than one building, and how much lightning you get. Build the system as an off-grid system with the steps above, then have the electrician make the house connection.

Ask the electrician which neutral-ground bond setting to use. With a transfer switch that does not switch neutral, the inverter’s bond goes off.

If Something Goes Wrong

What you see	What to check
Blank screen	Battery breaker on the inverter on, batteries on, power switch on. Measure battery voltage at the BAT terminals.
Battery communication warning (EG4 6000XP Warning 00, SGPWOSAY and SUNGOLDPOWER code 58)	Network cable in the BMS port on both ends. Battery type and protocol settings match the battery.
Battery shuts off when the inverter starts	Inrush current into the inverter’s capacitors can trip the BMS. On a Yixiang JK BMS, use the reset and Dis-limiter fix.
PV over-voltage (EG4 6000XP Fault 21, SGPWOSAY and SUNGOLDPOWER code 09)	Open the PV disconnect now. The string is over the max PV voltage. Take a panel out of the string (see Panels per string).
Solar charging far below the array rating	String voltage inside the MPPT range, PV disconnect on, no shade, and the max charge current setting not set low.
Overload (EG4 6000XP Warning 28, SGPWOSAY and SUNGOLDPOWER codes 13 and 14)	Turn loads off. Start large motors one at a time.
Low battery (EG4 6000XP Warning 26, SGPWOSAY and SUNGOLDPOWER code 01)	Charge from solar or a generator. Check the low-voltage cutoff setting.
Current on the ground wires, or GFCI outlets tripping	Two neutral-ground bonds. Keep only one (Helpful Tips above).

Codes come from each inverter’s manual. The EG4 12000XP uses its own list; look it up in its manual. If you are still stuck, post on the beginner forum with photos of the screen and your wiring.

My Latest Videos

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DIY Solar Power with Will Prowse

Van or RV

Boat

Cabin or Shed

Whole House

Off-Grid Solar System Builder

How the System Connects

What It Costs

Choose An "All-In-One Inverter"

Each unit has everything you need to go off-grid:

SGPWOSAY 5000W Inverter

EG4 6000XP Inverter

SUNGOLDPOWER 10000W Inverter

EG4 12000XP Inverter

The Four Inverters Side by Side

The inverters shown above MUST be mounted indoors. They cannot be mounted outside.

Choose a 48V Battery

Yixiang 16kWh

Yixiang 32kWh

RUiXU Lithi 16

ECO-WORTHY Cubix 100, 4-Pack

How Much Battery You Need

How long it lasts

Two or more batteries

Choose a Solar Panel Mounting Method

Currently the most popular method for mounting panels is to use a ground mount. This is why:

Ground Mount

Roof Mounted

Solar Carports

Choose Your Solar Panels

But keep a few things in mind:

Used Solar Panels

Current Connected

Signature Solar

How Many Panels Per String

Size a string for any panel

Obtain Materials and Supplies

Battery Cable, Fuses and AC Wire

What to buy

Shopping Checklist

Build Your System

01 / Mount Your Main Components

02 / Mount Your Solar Panels

03 / Wire Up Your System

04 / Connect the Solar Panels to Your System

05 / Turn Your System On.

That's it

Settings to Check After Startup

How to Safely Connect the Grid

Neutral-Ground Bond Setting

One Neutral-Ground Bond per System

Can I Back Up My Whole House With This System, Legally?

If Something Goes Wrong

My Latest Videos

Choose An  "All-In-One Inverter"

Obtain Materials  and Supplies