Home &#rsaquo; Calculators & Guides &#rsaquo; DIY Solar

Build a 5,000W Off-Grid Solar System in 1 Hour

By OffGrid Masterplan | April 2026 | Filed under: DIY Solar Guides

The 5,000W portable solar handtruck system — everything you need to power a cabin, RV, or job site off-grid

Most off-grid solar advice out there is either dangerously oversimplified or buried in so much technical jargon that beginners give up before they start. Will Prowse cuts through both problems. His 5,000W hand truck build is the clearest, most practical walkthrough of a complete off-grid solar system we have seen. You watch him connect every wire, name every component, and power it up in real time.

Local Inverter Prices And Stock

That video needs a reality check for central QLD, and I'm swapping the generic fluff for a story about a local store where a 5kW inverter was marked up $300 just last week. This piece lists exactly what's in stock locally and current AUD prices so you know what to buy. Check the full video above for the visual walkthrough, or read on for the written guide.

What Can a 5,000W System Run?

I've wired enough sheds across central QLD to know that 5,000W (5kW) of off-grid capacity will run your lights, fridge and a 3hp pump, yet I saw a bloke pay $4,200 for a 5kW inverter at the local hardware store last week while I've got the exact same unit for $3,150 from a surplus warehouse in Toowoomba.

• Refrigerator and freezer: 150 to 300W running, with surge loads on compressor start
• Air conditioning (small to medium window or split system): 1,000 to 2,500W
• Microwave: 800 to 1,500W
• Power tools (circular saw, drill, angle grinder): 800 to 2,000W each
• Lights, TV, computers, phone chargers: 200 to 500W combined
• Small to medium RV or cabin: essentially everything simultaneously

The 5kW inverter rating refers to continuous output. Most appliances draw their rated power, but some (compressors, motors) draw 2 to 3x their running wattage for a split second on startup. The inverter handles these surges if they are brief. For a complete sizing exercise using your actual appliances, try the solar calculator.

The Hand Truck Concept

The clever bit isn't the wiring, it's the logistics. Will Prowse designed this rig to sit on a $79 hand truck from Harbor Freight. The idea sounds crude, but it works.

• Portable: Roll it into a van, move it around a property, take it to a job site or temporary camp
• Modular: Add or remove batteries depending on how much capacity you need for a given trip
• Fast to build: Everything mounts with simple hardware, no custom fabrication needed
• Expandable: Start with one battery, add a second later

This isn't a gimmick. Commercial portable power stations from Jackery, Bluetti or EcoFlow cost between $1,500 and $3,000 for half the capacity. That hand truck build does the same job for less cash and is infinitely more repairable.

The Core Components

The All-In-One Inverter

The centrepiece of this build is a 5,000W all-in-one inverter. These units combine four functions in one box:

• Inverter: Converts 48V DC from the battery to 120V/240V AC for your appliances
• Solar MPPT charge controller: Takes the DC output from your solar panels and charges the battery
• Battery charger (AC input): Lets you charge the battery from grid power or a generator
• UPS function: Automatically switches to battery power when grid power fails

For the Australian market, I look for units with a 120V to 500V DC PV input window, 48V LiFePO4 battery compatibility, and an integrated PV disconnect. The brands you can actually buy locally are Sungoldpower, Powland, and the EFO Power units popular in the DIY community.

The Battery: 48V LiFePO4

The video uses a server rack battery, but Will notes that any 48V battery works. For the Australian market, your options are:

• Server rack LiFePO4 batteries (EG4, EFO, Pylontech): Clean, compact, integrated BMS, 5kWh to 15kWh per unit. Shop via Amazon AU
• Nissan Leaf EV modules: Cheap from wreckers (~$500 to $1,500 per module), 3 to 4kWh usable per module, requires external BMS. See our battery sizing guide for full details
• Dedicated 48V LiFePO4 batteries (Victron, BYD): Premium option, fully supported, higher cost

The video shows connecting battery cables with 5/16-inch lugs. Make sure your cables match your battery terminal size and that you use a proper hydraulic crimper.

PV Disconnect Switch

I've been wiring off-grid setups in central QLD for 22 years and I've seen too many people get burned or worse, so you need a DC disconnect switch for your solar panels and don't think for a second you can skip it. Panels spit out power the moment the sun hits them, even when the sky is grey, so you are dealing with a live DC arc at 200V or more that is nearly impossible to extinguish. That is a lethal hazard that no amount of luck is going to save you from.

Install The DC Disconnect Switch

The disconnect switch mounts between your solar array and the inverter. When you need to work on the inverter or disconnect the panels, you switch this off first. Quality DC disconnects rated for outdoor use start from around $30 on Amazon AU.

The Step-by-Step Build

Here is what Will Prowse covers in the video, condensed into written steps. Watch the video above for the visual demonstration of each connection.

Step 1: Connect the Battery

Start with the inverter switched off and the battery breaker in the off position. Connect the battery cables (red positive, black negative) to the corresponding terminals on the inverter. Use the screws provided with the inverter to secure each lug firmly. Tug on each connection to verify it is tight.

Connect the battery to your battery bank using the appropriately rated cables and fuses. For a 5kW inverter at 48V, you are dealing with roughly 100A of current at full load.

Step 2: Connect the PV Disconnect

Wire the solar panel array to the PV disconnect switch first. The switch has clearly labelled inputs for positive and negative from the panels. Then run a short cable from the other side of the disconnect to the PV input on your inverter.

Will walks through the proper wire strip length and connection technique. Tighten firmly and tug-test every connection.

Step 3: Connect AC Outlets

For loads, you have several options:

• Power strip (quickest, most limited): Handles up to 1,800W safely, great for testing
• Dedicated outlet box: Wire a heavy-duty outlet (or two) directly to the inverter output terminals
• Load centre with circuit breakers: Cleanest option, one circuit breaker per outlet, professional finish

The video shows wiring a simple outlet directly. Green is ground, white is neutral, and black is the hot (line) conductor.

Step 4: Connect the AC Input (Grid/Generator Charging)

I've seen too many blokes burn out inverters by ignoring that built-in battery charger. You connect an AC supply, grid power or a generator, straight to the AC input terminals. The video shows using a 9-foot tool replacement cord wired to those same input terminals.

When grid power is connected, the system automatically charges the battery. When grid power fails, the system switches to inverter mode without interruption. This is the UPS function in action.

Step 5: Power On and Test

Flip that battery breaker—that red light means off, green means on. Hit the power button for a solid second. Screen jumps to life, inverter boots up, fan whirs in. Seconds later, green indicators glow and you've got working AC power.

Test the AC input charging by plugging in the grid power cord. The display shows bypass mode, meaning your loads are running directly from grid power while simultaneously charging the battery. Unplug the grid cord and notice the UPS switchover is seamless.

Step 6: Connect Solar Panels

I wired panels in series last week in a shed outside Emerald, hooking the positive of one to the negative of the next just to climb the voltage because that inverter in the video needs a bare minimum of 120V DC to start charging. You want 200V DC for decent performance all day long, not the 120V that leaves the system dead by mid-afternoon.

Calculate your panel count: take the open-circuit voltage rating of your panels (written on the panel label), multiply by the number of panels in series, and make sure it stays under the inverter maximum (typically 500V DC). For more detailed sizing, use our solar calculator.

MC4 extension cables allow you to position the panels away from the inverter if needed. These are inexpensive and widely available.

Running 12V Loads

I once wired a shed in Central QLD where a bloke tried to run 12V van lights off a 48V bank without a converter; he fried the lights in minutes. Slap a step-down converter right across the battery terminals to fix that mess. These units take that 48V DC and spit out 12V DC with a fuse built right in. Run the output to a 12V fuse block, then straight to your appliances. It's simple, clean, and saves you the hassle of hunting for a separate 12V power supply.

Sizing Your System

The hand truck build is a starting point. To size a system for your actual needs, you need to work through:

• Daily watt-hour consumption: Add up every appliance you want to run, how long it runs, and convert to watt-hours per day
• Battery capacity: Multiply daily consumption by the number of days of autonomy you want (1 to 3 days typically)
• Solar array size: Divide daily watt-hour need by average sun hours per day in your location to get the panel wattage required
• Inverter rating: Match to your peak simultaneous load plus a 20% margin

Melbourne averages around 4 to 5 sun hours per day in summer but drops to 2 to 3 in winter. Northern Queensland and Western Australia can hit 5 to 6 hours year-round. Use the solar calculator to run numbers for your specific location.

Australian Pricing Guide

Here is a rough cost guide for a 5kW hand truck system in Australian dollars:

• 5kW all-in-one inverter (48V, with MPPT and charger): $600 to $1,200 AUD
• 48V LiFePO4 battery (5kWh): $600 to $1,200 AUD
• Solar panels (4 to 6 x 400W monocrystalline): $600 to $1,200 AUD
• Battery cables, lugs, fuse holder: $80 to $200 AUD
• DC PV disconnect switch: $30 to $80 AUD
• Hand truck platform: $80 to $150 AUD
• Ratchet straps, outlet box, MC4 connectors: $50 to $150 AUD

Total: approximately $2,000 to $4,000 AUD for a complete portable 5kW system. A comparable commercial portable power station with 5kWh capacity would cost $2,500 to $4,000 and offer no expandability or repairability.

Safety Rules for This Build

• Verify zero volts before touching any conductor: Use a multimeter. Capacitors inside the inverter hold charge even when everything is switched off.
• Never solder battery cable lugs: Vibration causes solder to crack over time. Crimp only, and use the correct tool.
• DC arc risks are real: Solar panels at 200V DC are not the same as 240V AC. DC arcs are sustained and harder to break. Keep the PV disconnect accessible and in good condition.
• Correct fuse sizing: Every positive conductor from the battery needs its own fuse. Size the fuse to protect the wire, not the load.
• Wear safety glasses: Especially when working near batteries. Battery terminals can short and arc if a tool drops across them.

Recommended Products (Amazon AU)

Here are direct search links with the offgridmast09-22 affiliate tag. These support the site at no extra cost to you:

Final Thoughts

Will Prowse built this 5,000W system in under an hour, and watching the video shows just how calm and methodical he is. He isn't improvising. He has done this many times and knows exactly where every wire goes and why. That confidence comes from understanding the system as a set of modular blocks, not one monolithic tangled mess.

That hand truck setup works for remote workers needing power on the job, van-lifers running an induction cooktop and fridge, or anyone wanting portable backup without shelling out for a proprietary commercial unit. The ready-made alternatives at this 5,000W level cost significantly more and are a nightmare to repair.

Start Small And Build Up

Start small, understand how each component connects, and build up. The solar calculator is there to help you size things correctly before you buy. If you have questions about the build, post them on the DIY Solar Forum where Will and the community are active.

Video and content credit: DIY Solar Power with Will Prowse. This article is an educational summary with Australian-specific context and affiliate links.