Code-Compliant 48V System

Permit & inspection ready ~$13,500

Build a safe, reliable 48V solar system with code-compliant components designed to work together. From power generation and storage to protection and distribution, every part is selected for dependable performance, easier installation, and long-term off-grid use.

Affiliate links below

What Is Hybrid Inverter?

Hybrid Inverter: An inverter that can be connected to the grid and backfeed excess power AND run your entire home off-grid.

But hybrid inverters cost more money than running my house with offgrid specific inverters! Why would I choose a hybrid instead?

Mainly for these reasons:

Hybrid inverters are outdoor rated and more durable than an offgrid inverter. Instead of having to mount your batteries and inverters indoors and listen to the loud and annoying cooling fans all day, you can throw a hybrid inverter outside and forget about it. Just be sure to use outdoor rated batteries (like the vertical mount outdoor rated power pro, click here)
Easy for any electrician to install and permit. Buy the hybrid inverter and batteries, and get someone else to install it if you do not feel comfortable doing that.
Better Warranties. Hybrid Inverter warranties are better because they are more durable devices.

Better Surge Capacity. Hybrids can usually start an air conditioner, even the small ones! I still recommend adding a soft start to any air conditioner that is running off an inverter though.
The software is a million times better. Every hybrid on the market has wifi control, color touch screens (or you can add them optionally), data logging and more.
Faster Payback Period. If you have a good net metering program with your utility, you can use the hybrid inverter to dump excess energy into the grid to create income or credits. This will allow you to run a smaller battery and have a faster return on investment.

EG4's Easy to Scale Hybrid System

With this system, the Flex Boss is the Hybrid Inverter. And the Grid Boss is considered a “gateway”. The gateway goes between all components of your system.
The install is dead simple because of the gateway. Just have an electrician install the flex boss between your meter and your house’s main breaker panel, and then you can add inverters and batteries to your house whenever and wherever you need to. Instead of wiring up hybrid inverters with large transfer switches right next to your panel (very difficult and expensive), the flex boss allows you to mount the batteries and inverters far from the panel.
This decreases the complexity of the system greatly!

Hybrid Without Gateway

Hybrid With Gateway

Instead of wiring up multiple disconnect switches and fitting all of your batteries between your meter and your panel, you can install a gateway! This allows you to simplify the entire system and makes it a million times easier to get it approved by local inspectors. Most new hybrid systems are now using a gateway for this reason.

Previously you would have to use large conductors to each inverter/battery stack. For example, the 18kpv. If you want to use 2 inverters (which a lot of houses need), you would need to spend thousands on large conductors to each inverter.

Look at the example below. Imagine stuffing all of those batteries between the meter and the panel. Instead you could install a gateway like the grid boss, and run wires out to the inverters/batteries instead (as pictured)

This allows you to mount your inverters and batteries wherever you wish. Instead of running 2/0 cables to each inverter, you can use 4 AWG instead! This makes the entire install very beginner friendly and easy to scale in the future.

Flex Boss Capabilities

Capabilities of a single flex boss:

120/240V Inverter with 12kW output w/ Battery Alone. If you have solar connected, it bumps up to 16kW.
Peak AC Power is 24kW for half a second and 15 kW for 6 minutes!
21kW Solar Input and 600VDC Input
Closed Loop Communication with EG4 Batteries
Rapid Shut Down Built-in
PV Disconnect Built-in, no need for combiner box
Expensive breakers included. No need to buy them seperate.

Now if you connect 3 flex boss inverters together with a grid boss, the numbers get crazy:

Now the absolute limit of the flex boss is paralleling 16 of them with disconnects/combiner boxes (not recommended, but possible).

This will increase the output even more. You could easily run a neighborhood:

Grid Boss Capabilities

Essentially the grid boss is a large transfer switch with intelligent features. Not only does it allow you to connect multiple hybrid inverters, but you can connect EV chargers, air conditioners and water heaters with the smart port functionality. This allows you to automate your home solar system. If you are generating too much power, you can direct all of that energy into your water heater, for example. Or if your system is running low on power for a few days, it can turn off the EV charger. Whatever you wish!

Maximum of 3 EG4 hybrid inverters (Flex boss, 12kpv and 18kpv)
Generator Input and Management
Critical and Non-critical Load Terminals! Run two breaker panels from a single grid boss.
4 Smart Ports. Controllable outputs for EV's, water heaters or whatever you wish.
Outdoor rated. Mount it outside between your house and load breaker panel and forget about it.
Connect pre-exisiting grid tie solar systems! If you have a solaredge or enphase system, or any other, you can connect it to the grid boss and monitor it remotely.

How Do You Design a System?

Because the flex boss has a massive PV input, the most common limiting factor to consider is the inverter output.

If you have a tiny home or cabin, or a very small house without air conditioner, 1 flex boss and 1 grid boss will be perfect.

If you have a normal sized home with a large air conditioner, you will need 2 flex boss and 1 grid boss.

If you have a large home with multiple air conditioners and an EV charger, you will need 3 flex boss and 1 grid boss.

Whats nice about this system is that you can always expand your system at any time. If you can only afford 1 flex boss to assist in running your house, but you want to add a second one next year, that is easy to do. So buy what you can afford, and add more later. Once the grid boss is installed, it easy to add or remove inverters or batteries whenever you need to.

EG4 FlexBOSS21 & GridBOSS

Revolutionize your solar setup

How to Purchase the Flex/Grid Boss

Most people will choose from these four packages:

Now You Need Batteries

The flex/grid boss is designed to work outdoors. So you need an outdoor rated battery. The only battery that communicates with the flex boss and has an outdoor rating is the powerpro battery.

So for each Flex Boss, you will need 2X Powerpro Batteries

EG4 WallMount Lithium Battery

AllWeather Energy Storage

Need Cheaper Batteries?

If you are running your system indoors, you will save a ton of money by not purchasing outdoor rated batteries. The most popular option is to run the indoor powerpro.

And you can take it a step further and make your own batteries with raw cells. The flexboss can work with any battery you wish. It may not pass inspection, but it will absolutely work. Just disable the battery communication and set your charge voltage and low votlage disconnect and you’re set. This way you can use whatever battery you wish!

Or you can use a budget battery! Click here to check out Budget 48V Batteries

Now that you have your inverter/gateway/battery situation taken care of, you need some solar panels and ground mounts!

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.
The most popular size for offgrid is 400-440W bifacial. These are small and easy to install for beginners.
Can easily mount them to concrete, dirt, concrete roof or use a ballast! You can mount them anywhere.

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.

Once You Have Everything, You Can Now Install It!

It is a pretty straight forward install. Check out my videos if you want to see how it is done.

If something is confusing or difficult, hire an electrician to do it instead!

The Flex Boss is Fantastic for Offgrid Use as Well

Another option is to run the flex boss in offgrid mode! You will not need to purchase the grid boss, and you can now have an offgrid system that you can mount outdoors.

Fully Off-Grid System

Other Hybrid Systems that I Recommmend:

EP Power Cube

Best software but hard to scale.
Can only scale to 40kWh. And you must use proprietary high voltage battery.
120/240V AC Output: 7.4kW with 1 Inverter, and 15.2kW with 2 inverters. Pretty limited compared to EG4.
Fantastic software. Easy to install the system and set it up.
Fantastic customer service and support.
Look aesthetically pleasing.
The batteries are 77 pounds each, making installation much easier than others out there.

If you can run your entire house with 15.2kW, this thing rocks. But if you need more power, you will need an EG4 or something else.

I actually run my main house off this system and absolutely love it! But unfortunately I cannot scale it. Great product if it fulfills your needs though!

Canadian Solar EP Cube System

Modular whole-home battery system with smart energy management, seamless backup, and up to 15.2kW of output.

EG4 18kPV Hybrid Inverter

12kW split-phase inverter with 18kW solar input, 48V battery support, and grid or off-grid operation.

EG4 18kPV-12LV

This used to be my absolute favorite hybrid inverter. I ran it for years and had zero issues. But then the flex boss/grid boss came out and now this thing is outdated. The installation cost is much higher, and the stats are not nearly as good as the flex boss.

If you have a small house and 12kW can run everything, this thing is great! But if you have anything larger than that or more than one air conditioner, you will need the grid/flex boss system for sure.

All-In-One Hybrid Solar Inverter

With 18kW of PV input and 12kW of continuous output power, why pick anything else for your home?

The ultimate power solution:

Comprehensive Certifications

Certifications for Safety, Grid Connection, EMC, and Outdoor Ratings

Code Compliant Option Of the Past: Sol-Ark

Expensive, but very easy to use!

Just buy the unit online and hire an electrician to install it. That is it. This unit can do grid tie only, offgrid and net zero export. And sol ark will set it up for you remotely. The cost is justified if you want something that will last for decades and have zero issues.

Features of the  Sol Ark:

Another option is to run the flex boss in offgrid mode! You will not need to purchase the grid boss, and you can now have an offgrid system that you can mount outdoors.

Two Built-In 500V MPPT Charge Controllers
1 – 6 PV Strings
Battery Disconnect
48V Battery Input
Auto-Generator Start, works with any generator that has 2 wire start.
Rapid Shutdown Signal
Built in Arc Fault and Ground Fault detection
Current Sensors Included
Battery Communication for LiFePO4.
Works with any battery type, FLA, AGM, SLA, LFP.
PV Disconnect
Wiring Knockouts an & WiFi
50A Breakers:
- AC In/Out, AC Load Out
- AC Gen In/Smart Load Out
Remote programmable monitoring and configuration included

Next Generation Efficiency. 93% RTE – The most efficient in the world in/out of batteries
120/240V single/split phase & 120/208V three-phase in the same unit. Stackable up to nine in parallel
Easy AC-couple retrofit
No microinverters, no optimizers necessary on new installs
All-in-One box
- Easy plug ‘n play install and inventory management
- Everything needed for Grid Tied, Hybrid, or Off-Grid inside
- Manages power from Solar, Battery, Grid, Load, and Generator simultaneously
10-Year Standard Warranty Included

Two Ways to Build with Sol-Ark

Choose the standalone Sol-Ark 15K for a custom build, or start with a UL9540-certified Sol-Ark and Pytes system with expandable  battery storage.

Sol-Ark + Pytes UL9540 ESS

Certified hybrid system with Sol-Ark inverter, 15.3kWh Pytes storage, expandable whole-home backup.

Sol-Ark 15K Hybrid Inverter

All-in-one 15kW inverter with 19.5kW solar input, 48V battery support, and integrated whole-home transfer.

My Latest Videos

Visit my Channel

DIY Solar Power with Will Prowse

Van or RV

Boat

Cabin or Shed

Whole House

Code-Compliant 48V System

What Is Hybrid Inverter?

Mainly for these reasons:

EG4's Easy to Scale Hybrid System

Hybrid Without Gateway

Hybrid With Gateway

Flex Boss Capabilities

Capabilities of a single flex boss:

Now if you connect 3 flex boss inverters together with a grid boss, the numbers get crazy:

Grid Boss Capabilities

How Do You Design a System?

EG4 FlexBOSS21 & GridBOSS

How to Purchase the Flex/Grid Boss

Now You Need Batteries

EG4 WallMount Lithium Battery

Need Cheaper Batteries?

Now that you have your inverter/gateway/battery situation taken care of, you need some solar panels and ground mounts!

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

Once You Have Everything, You Can Now Install It!

The Flex Boss is Fantastic for Offgrid Use as Well

Fully Off-Grid System

Other Hybrid Systems that I Recommmend:

EP Power Cube

Canadian Solar EP Cube System

EG4 18kPV Hybrid Inverter

EG4 18kPV-12LV

All-In-One Hybrid Solar Inverter

The ultimate power solution:

Comprehensive Certifications

Certifications for Safety, Grid Connection, EMC, and Outdoor Ratings

Code Compliant Option Of the Past: Sol-Ark

Expensive, but very easy to use!

Features of the Sol Ark:

Two Ways to Build with Sol-Ark

Sol-Ark + Pytes UL9540 ESS

Sol-Ark 15K Hybrid Inverter

My Latest Videos

Features of the  Sol Ark: