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Off-grid storage inverters are not a smaller version of the hybrid on a suburban roof. The useful shortlist for a cabin, a farm, a telecom hut or a village mini-grid is Victron Energy, Voltronic Power, Deye, Schneider Electric and Studer Innotec. Two of those sell a brand you can put on a quotation. One of them sells to almost nobody under its own name, which is exactly why it belongs on a supplier list.

The ranking is for buyers who need an inverter-charger: a unit that runs loads from a battery, charges that battery from solar or a generator, and switches between those sources without dropping the lights. Shipment volume is a weak guide here. A huge share of the "brands" in this segment are labels on someone else's hardware, so the question is who actually builds the unit and who pays when it fails.

Last updated: October 2026. Specs come from current datasheets and manufacturer warranty texts. Off-grid ranges are revised constantly, and a model sold in Australia is often not the model sold in Africa. Confirm the exact SKU.

The five, side by side

RankSupplierBaseWhat you are really buyingBatteryWarranty you can trace
1Victron EnergyNetherlandsA branded inverter-charger with published surge and transfer specs48 V, open BMS supportStandard Victron warranty, local repair network
2Voltronic PowerTaiwanThe factory behind a large share of off-grid badgesMostly 24 V and 48 VThe brand on the box, not Voltronic
3DeyeNingbo, ChinaA light hybrid that also runs off-grid and accepts a generator48 V lead-acid or lithiumUp to 10 years, from Deye
4Schneider ElectricFrance / globalThe Conext XW Pro, built for backup and remote sites48 V, including lithiumSchneider, with field-replaceable boards
5Studer InnotecSion, SwitzerlandA small-volume inverter-charger, assembled in Switzerland12 V to 48 V10 years, from the factory that built it

Weight tells you as much as the warranty column. A 5 kW Deye hybrid is about 17 kg. A Schneider XW Pro is about 55 kg. That gap is the transformer. Low-frequency, transformer-based inverter-chargers start motors and well pumps that lightweight high-frequency units shut down on. If the load list includes a compressor, a water pump or a workshop, start with the heavy units and treat the light ones as a different product.

The badge on the carton is not the supplier

This segment is full of brands that do not own a factory. Voltronic Power, listed in Taiwan and headquartered in Taipei, describes itself as a design-and-manufacturing supplier and says outright that it has no brand of its own and does not compete with its customers. Its Axpert family — King, MAX, VM, MKS and the rest — is what a lot of African, Asian and Latin American "off-grid inverter brands" actually are. Voltronic reports more than 300 customers across about 135 countries, with factories in Taiwan, Shenzhen, Zhongshan and Vietnam.

That is not a scandal. It is a sourcing fact. If three quotations in your inbox look identical down to the LCD menu, they probably left the same line. Ask for the IEC 62109 report and see whose name is on it. Then ask who ships the replacement board. A 2024 supply letter from Voltronic to one brand customer offered twelve months of factory cover from delivery, with a promise of no sudden end-of-life before 2026. That letter is the factory talking to the brand. The warranty your customer reads on the sticker is a different contract, written by whoever owns the badge, and it is only real if that company is still answering email in year four.

1. Victron Energy: the reference design

Victron, based in the Netherlands, is the inverter-charger other datasheets get compared with. The split in its range is simple and worth memorising. A MultiPlus has one AC input, for grid, shore power or a generator. A Quattro has two, and it connects itself to whichever source is live, which is what you want when a site has both a weak grid and a diesel set. On both families the main output is a no-break output: Victron's datasheet says the transfer takes less than 20 milliseconds, fast enough that a computer does not reboot. A second output is live only while AC input is present, so a water heater can be kept off the battery.

Two functions matter more than the transfer time. PowerControl caps the current drawn from a small generator so the inverter uses only the spare capacity for charging. PowerAssist goes further and borrows from the battery when a load briefly exceeds what the generator can give, then pays it back when the load drops. That is the difference between sizing a generator for the peak and sizing it for the average. Units parallel and stack into three-phase, and a Cerbo GX or Ekrano GX puts the system on Victron's free VRM portal, which is the main reason installers accept the price: they can see a remote site without driving to it.

The limit is cost and the learning curve. A Victron system is a kit of parts — inverter-charger, MPPT, GX device, battery — rather than one box. Budget the accessories into the quotation or the cheap alternative will look cheaper than it is.

2. Voltronic Power: buy the factory, not the sticker

If your market wants an off-grid inverter at a price Victron will not touch, you are probably going to sell a Voltronic design whether you planned to or not. The Axpert catalogue is wide on purpose: single and dual AC outputs, duplex models that switch between two AC sources, a King variant advertised with zero transfer time, and VM high-frequency units alongside heavier MKS-style models. Power runs from a little over 1 kW into the 11–12 kW class, almost all of it aimed at 24 V and 48 V batteries, with BMS ports on the newer lines.

The buying decision is which contract you are on. Buying from Voltronic, or from a brand that will show you the Voltronic supply agreement, means you know the hardware revision and you can negotiate spares. Buying a third-tier badge that will not name its factory means you own every failure yourself. Ask three things before the deposit: the part number Voltronic uses internally, the firmware update path, and what happens to warranty stock if that brand owner disappears. The hardware can be perfectly good. The brand wrapped around it is the risk.

3. Deye: the hybrid that will also live off the grid

Deye's low-voltage hybrids, such as the SUN-5K-SG04LP1, are not classic inverter-chargers, and pretending they are is how projects get mis-specified. A 5 kW unit weighs about 17 kg, runs a 40–60 V battery at up to 120 A of charge and discharge, tracks two MPPTs, passes about 35 A of AC straight through, and will deliver twice rated power for ten seconds. It is rated to store energy from a diesel generator, it AC-couples onto an existing solar system, and Deye allows up to 16 units in parallel for on-grid and off-grid use. The AU datasheet quotes a 10-year warranty and IP65.

That is an excellent product when the site is a house that sometimes loses the grid, or a small business that wants solar, a 48 V lithium rack and a generator socket in one wall-mounted box. It is a poor product when the site is a borehole pump and a cold room. Ten seconds at double power will not start every motor that a transformer-based 5 kW unit will, and the fan on the larger models is audible in a living space. Deye's own shipments show where the company is pointed: storage inverters up 48% in the first half of 2025. Buy it as a volume hybrid with a real off-grid mode, and keep Victron, Schneider or Studer on the quote when the load is inductive and the road to the site is long.

4. Schneider Electric: the one utilities already know

The Conext XW Pro is Schneider's off-grid and backup inverter-charger, a 48 V unit rated at 6,800 W with a 140 A charger, 95.7% peak efficiency and a weight of about 55 kg. It supports DC-coupled and AC-coupled layouts, charges lithium packs, and scales from a single unit into three-phase clusters. Schneider designed it against utility rules such as California Rule 21, which matters when the same hardware has to be legal both as a backup inverter and as an off-grid inverter.

The reason to specify it is institutional. Schneider can sell into projects where the consultant's approved-vendor list has four names on it, and the XW platform has a long installed base with field-replaceable boards rather than a sealed throwaway box. Monitoring and firmware go through the Conext Gateway. You will not win a price fight with a Voltronic badge, and you should not try. You win the tender that asks for a named manufacturer, a surge curve and a service plan.

5. Studer Innotec: small factory, long promise

Studer Innotec builds the Xtender range in Sion, Switzerland, and the manual says so in plain language: manufacture, assembly and test happen at that factory, and the warranty period is 10 years. The smaller xts covers roughly 900 to 1,400 VA in an IP54 enclosure and parallels up to nine units, or three-phase to about 12.6 kVA. Larger Xtender models carry the same idea further up the power range. Smart-Boost plays a similar role to Victron's PowerAssist, topping up a weak generator from the battery, and the units are known for tolerating the poor voltage a small diesel actually produces.

This is a specialist product with specialist lead times. You stock it for customers who have been burnt by a sealed inverter they could not repair, and who will pay for a 10-year warranty from the company that wound the transformer. You do not bid it into a hundred-unit rural electrification tender against Shenzhen pricing. Studer's exclusion list is also unusually honest — wrong battery voltage, reversed polarity, condensation, lightning — so read it before you promise cover you cannot pass upstream.

Also worth a look

Growatt SPF off-grid inverters are widely stocked and easy to price, with the same caveat as any high-frequency unit: check the surge duration, not the marketing peak. MPP Solar PIP models are widely understood in the trade to be Voltronic-family hardware under another brand, which makes them a sourcing route rather than a separate factory. Must and SRNE (Shenzhen) cover the low-cost 48 V end and sell well into Africa and the Middle East. Luxpower is better thought of as a hybrid brand that can run off-grid than as an inverter-charger maker. For a lithium rack rather than the inverter, the relevant comparison is on our energy storage vendor list.

Size the surge, then size the generator

Nameplate watts are the wrong first number. A fridge, a pump or a compressor can draw several times its running current for a fraction of a second, and an inverter either has the transformer to supply that or it doesn't. Transformer units publish a short peak well above their continuous rating and hold a useful overload for tens of seconds. High-frequency units often quote "twice power for ten seconds" and then fold. Write the motor loads down with their starting current, and match that column before you match price.

The generator is the second sizing trap. An inverter-charger with PowerAssist or Smart-Boost can let you specify a smaller set, because the battery covers the peaks and the generator runs nearer its efficient load. That only works if the inverter will actually charge from the generator you have. Dirty voltage and slow governors make cheap chargers drop offline. Victron, Schneider and Studer publish this as a feature because their customers run generators every day. On a Deye or a Voltronic duplex model, confirm generator support on the exact SKU, including the maximum charge current while the set is also carrying loads.

Then decide 48 V versus high voltage. Almost everything on this list is a 48 V machine, and that is a virtue off-grid: the battery bank is serviceable, a dead module can be isolated, and the charge currents, while high, are well understood. A 5 kW inverter at 48 V needs on the order of 100 A continuous, so cable cross-section, fuse rating and terminal torque are part of the inverter choice, not an afterthought for the electrician. High-voltage batteries belong on grid-tied hybrids. They are the wrong default for a site nobody visits for six months.

Specifying batteries, cable and DC protection for an off-grid site?

What to put in the purchase order

  • Continuous power at 40°C, not at 25°C. Victron derates in the datasheet. Many cheaper sheets quote the flattering number only. Sites in containers and plant rooms live at the higher figure.
  • Surge, in seconds. Get the overload curve. "Peak power" with no duration is not a spec.
  • Transfer time on the output you will actually use. Under 20 ms keeps electronics up. A second output that dies with the grid is useful, but only if you planned the circuits that way.
  • Generator behaviour. One AC input or two, maximum charge rate from the set, and whether the inverter accepts a small diesel's voltage swing.
  • BMS protocol. CAN or RS485 means nothing until your battery is on the compatibility list. Closed lists are how storage projects stall at commissioning.
  • Parallel rules. "Up to 16 units" still has rules about cable length matching and firmware. Get them in writing if you are building a three-phase cluster.
  • Who holds the spare board. A sealed high-frequency unit is a swap. A transformer unit with replaceable boards is a repair. Price one spare into the project, sitting in the same country as the site.
  • The name on the test report. If it does not match the name on the carton, you are buying a brand owner's promise. Decide consciously whether that is acceptable.

Where ShineTong fits

ShineTong does not build inverter-chargers, and we are not going to insert ourselves between Victron and Studer. What we ship into off-grid projects is the part that fails when it is treated as an accessory: LiFePO4 storage for 48 V banks, storage accessories, DC breakers, isolators and cable sized for the current, not for the brochure.

A 48 V, 5 kW inverter is a 100 A DC circuit. Undersized cable and a breaker chosen from a grid-tied catalogue are the usual reason a good inverter looks unreliable. Distributors ask us to put the battery modules, the DC protection and the cabling in one inspected shipment, with documents matched to the destination, while they buy the inverter-charger from whoever their market already trusts. If you want that split — branded power electronics from the specialist, storage and protection from one supplier — send the inverter model and the battery voltage. We will tell you what we can stand behind and what we cannot.

Building an off-grid storage shipment?

Tell us the battery voltage, the inverter you are pairing it with, and the destination. We reply with options, documents and lead times. No public price lists.

Related reading

Frequently asked questions

What is the difference between an off-grid inverter and a hybrid inverter?

An off-grid inverter-charger is built to be the power source. It creates the AC waveform from the battery, charges from solar or a generator, and may never see a grid. A hybrid inverter is built to sit on a grid, store surplus solar, and keep selected loads up during an outage. Several hybrids, including Deye's low-voltage range, have a genuine off-grid mode. They still tend to be high-frequency designs with limited surge, so they suit houses better than sites with large motors.

Why do so many off-grid inverter brands look identical?

Because many of them are. Voltronic Power in Taiwan builds the Axpert family as a contract manufacturer and does not sell an own brand, so distributors put their own logo on the same platform. Identical menus are a hint. The IEC test report and the spare-parts agreement tell you whether you are dealing with the factory or with a label.

Does transfer time matter off-grid?

It matters whenever something electronic is running. Victron specifies a transfer under 20 milliseconds on the main output, which is fast enough for computers and routers to ride through. Loads that can blink, such as lighting, do not need that speed. Check which output is the no-break output. On several of these units a second output switches off on purpose when the grid or generator disappears.

Can I use a high-voltage battery off-grid?

You can, but 48 V is the better default for remote sites. High-voltage batteries are matched to grid-tied hybrids, and a failure often takes the whole pack offline until a technician arrives with the right module. A 48 V bank is heavier on cable and fusing, and it is serviceable. If you do choose high voltage, the inverter and the battery have to be on each other's compatibility list, not merely "CAN bus" in both brochures.

Who honours the warranty on a rebadged inverter?

The company whose name is on the warranty card. The factory warranty, where it exists, is usually a short promise to the brand owner — one Voltronic supply letter offered twelve months to the buyer — and it does not automatically extend to the homeowner or the village project. If you import a branded unit, get the warranty terms, the registration window and the return address before you sell it. A low price with no in-country spare is a deferred cost.

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